Astm stp 1593 2016

Synchronizing and Integrating Standards into Next Generation First Responder Personal Protective Equipment Development: An Implementation of the National Philip Mattson, John Merrill,

Selected Technical Papers

Performance of

Protective Clothing and Equipment:

10th Volume, Risk

Reduction Through Research and Testing

STP 1593

Editors:

Brian Shiels

Karen Lehtonen

Editors: Brian Shiels and Karen Lehtonen

Performance of Protective

Clothing and Equipment:

10th Volume, Risk Reduction Through Research and Testing

ASTM STOCK #STP1593

DOI: 10.1520/STP1593-EB

ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959 Printed in the U.S.A.

ISBN: 978-0-8031-7631-7

ISSN: 1040-3035

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September, 2016

THIS COMPILATION OF Selected Technical Papers, STP1593, Performance of Protective Clothing and Equipment: 10th Volume, Risk Reduction Trough Research and Testing, contains peer-reviewed papers that were presented at a symposium held January 28–29, 2016, in San Antonio, Texas, USA Te symposium was spon-sored by ASTM International Committee F23 on Personal Protective Clothing and Equipment.

Symposium Chairpersons and STP Editors:

Brian ShielsPBI Performance Products, Inc

Charlotte, NC, USAKaren Lehtonen

LIONDayton, OH, USAForeword

Synchronizing and Integrating Standards into Next Generation First Responder

Personal Protective Equipment Development: An Implementation of the National

Philip Mattson, John Merrill, Teresa Lustig, and William Deso

Assessing Design and Materials for Flame-Resistant Garments 11 Margaret Auerbach, Thomas Godfrey, Michael Grady, and Margaret Roylance

Theories from Evaluation: How Arc Flash Protective Fabrics Work to

Hugh Hoagland, Stacy L Klausing, and Jill A Kirby

A Heat Transfer Analysis and Alternative Method for Calibration of Copper Slug

Thomas A Godfrey and Gary N Proulx

An Evaluation of the Efects of Bleach Products and Fabric Softener on Properties

of a Common Flame-Resistant Cotton-Nylon Fabric 63 Jill A Kirby, Stacy L Klausing, and Hugh Hoagland

Parametric Study of Fabric Characteristics’ Efect on Vertical Flame Test

Performance Using Numerical Modeling 78 Esther Kim, Nicholas Dembsey, and Thomas A Godfrey

Advanced Layering System and Design for the Increased Thermal Protection of

Anita Nagavalli, Alexander Hummel, Halil I Akyildiz, John Morton-Aslanis, and Roger Barker

Contents

Ghulam Murtaza, Jane C Batcheller, Stephen A Paskaluk, and Mark Y Ackerman Efects of Convective and Radiative Heat Sources on Thermal Response of Single- and Multiple-Layer Protective Fabrics in Benchtop Tests 131 David Torvi, Moein Rezazadeh, and Christopher Bespfug

High-Intensity Thermal Testing of Protective Fabrics with a CO 2 Laser 159 John Fitek, Margaret Auerbach, Thomas A Godfrey, and Michael Grady

Comparisons of Two Test Methods for Evaluating the Radiant Protective

Performance of Wildland Firefghter Protective Clothing Materials 178 Alex Hummel, Kyle Watson, and Roger Barker

Experimental Study of Heat Flux in Propane Flash Fires 195 Stephen A Paskaluk and Mark Y Ackerman

Considerations for Applying Man-in-Simulant Test Methodologies for the

Evaluation of Fully Encapsulating Chemical Protective Ensembles 212

R Bryan Ormond

Permeation of Active Ingredient in Pesticide Formulations Through Single-Use and

Anugrah Shaw, Ana Carla Coleone, and Joaquim Machado-Neto

Development and Validation of an Alternative Chemical Permeation Test Cell 250 Christopher J Mekeel and Pengfei Gao

Interlaboratory Variation for Permeation Test Standards and Considerations for

William Gabler and R Bryan Ormond

Use of Thermal Mannequins for Evaluation of Heat Stress Imposed by Personal

Xiaojiang Xu, Julio A Gonzalez, Anthony J Karis, Timothy P Rioux, and

Adam W Potter

Heat Strain in Chemical Protective Coveralls—Are Thermal Sweating Mannequin

Tests More Informative than Sweating Hot Plate Tests? 296 ShuQin Wen, Jane Batcheller, and Stewart Petersen

Alternative Methodologies for Determining the Impact of Clothing Ventilation in

Structural Firefghter Turnout Suits 313 Meredith McQuerry, Emiel DenHartog, Roger Barker, and Alex Hummel

Development of a Human Sensation-Relevant Method for Measuring Phase

Daniel B Howe, Keith R Blood, Rick R Burke, and Nathan Lanci

J D Dale, S A Paskaluk, and E M Crown

Why Does the Structural Integrity of Flame-Resistant Protective Clothing

Vincent Diaz

Back Protector Performance—Standard Methodologies Versus Realistic Testing 391 Jean-Phillippe Dionne, Ming Cheng, Jef Levine, Matthew Keown, and Aris Makris

Te symposium was preceded by two very full days of standards development during a bi-annual meeting of ASTM Committee F23 on Personal Protective Cloth-ing and Equipment To open the event, the symposium co-chairs invited Lieutenant Jim Reidy of the San Antonio Fire Department to deliver a welcome speech Te lieutenant’s talk served as an excellent reminder to all those in attendance of the im-portance of ongoing research and testing and gave a personal connection to an end user whose life ofen depends on our success

Te overall objective of the symposium was to provide a forum for discussing the current state and future of the personal protective clothing and equipment industry Specific bjectives included:

• Showcase current research and advances in personal protective clothing and equipment

• Defi e and discuss challenges facing those developing, testing, and using sonal protective clothing and equipment

per-• Promote communication and information sharing between researchers, facturers, users, and government agencies

manu-• Assess the need for new and/or revised standards

Although many of the presentations covered topics involving fame exposures, the symposium co-chairs were pleased to welcome several discussions on the topics of chemical and biological protection, arc fash protection, and blast protection for mili-tary and law enforcement Te span of topics also shed light on important emerging issues, including a better understanding of physiological impact of protective cloth-ing, and innovative ways to reduce heat stress Particularly useful for the F23 Com-mittee members in attendance were the topics focusing on improving upon existing test methods to better serve the protective clothing industry

Overview

tributions to planning throughout the many months preceding to the symposium Furthermore, this STP would not have been possible without the attentiveness and countless hours volunteered by our peer reviewers to ensure that all of the following manuscripts were ft for publication It is our sincere hope that these selected techni-cal papers contribute signifi antly to the further advancement of personal protective equipment

Symposium Co-chair and Editor Symposium Co-chair and Editor

Philip Mattson,1John Merrill,1Teresa Lustig,1and

William Deso1

Synchronizing and Integrating

Standards into Next Generation

First Responder Personal

pp 1–10, doi:10.1520/STP159320160017 2

ABSTRACT

The Science and Technology Directorate of the U.S Department of HomelandSecurity is embarking on an ambitious program to develop a system ofintegrated plug-and-play personal protective equipment (PPE) and tools toprovide multilayer threat protection and up-to-the-moment situationalawareness to first responders The Next Generation First Responder (NGFR)program will integrate ruggedized advanced information-delivery tools withPPE ensembles across responder disciplines and operational environments thatprovide resistance to fire and puncture, protection from splash and liquid

Manuscript received January 27, 2016; accepted for publication March 3, 2016.

1 U.S Department of Homeland Security, Science & Technology Directorate, 245 Murray Ln SW, Washington,

DC 20528-0210

2 ASTM Tenth Symposium on Performance of Protective Clothing and Equipment: Risk Reduction Through

Research and Testing on January 28–29, 2016 in San Antonio, TX.

Copyright V 2016 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.

STP 1593, 2016 / available online at www astm org / doi: 10 1520/STP159320160017

penetration, and improved usability and comfort Standards, and an integratedapproach to address the various facets of the NGFR project, are criticalenablers to accomplish this vision The National Strategy for CBRNEStandards, published by the National Science and Technology Council,Committee of Homeland and National Security, through the Subcommittee onStandards, provides the structure for this approach The strategy describes theelements of a standards and testing infrastructure needed to counterchemical, biological, radiological, nuclear, and explosive (CBRNE) threats whilerecognizing that the CBRNE mission may be only one component of whatusers do each and every day The strategy’s sixgoals reflect not just thetechnical performance of the technology but the interoperability with theirsuite of equipment as well as concepts of operations involved in theirdeployment and the training of the users This paper discusses how thestrategy framework facilitates the integration of standards into the highlycomplexNGFR program and facilitates the transition of the technology tooperational use.

indi-To fully support the deployment ofa standard-based capability, a number ofothersteps should be addressed These could include an appropriate means to demonstrateconformity to the standard, training on the capabilities and limitations associated withthe standard, and guidance on procuring the technology and incorporating this newcapability into operations These considerations are addressed by a number of organi-zations focused on standard development, which include the National Institute forOccupational Safety and Health, the Department of Justice’s National Institute of Jus-tice, and the Department ofHomeland Security, among others

The National Science and Technology Council Committee on Homeland andNational Security released a document in May 2011 titled A National Strategy forCBRNE Standards [1] that addressed these issues This strategy outlined the ele-ments of a standards and testing infrastructure for detection, decontamination, andpersonal protective equipment (PPE) needed to counter chemical, biological, radio-logical, nuclear, and explosive (CBRNE) threats The strategy outlined a structure

to facilitate coordination of CBRNE activities among federal agency leaders; gram managers; the research and development, testing, and evaluation community;and the private sector Although a formal plan for implementing the strategy at thefederal level was not established, this paper uses the national strategy as a frame-workto coordinate and integrate standards issues for a very ambitious and complexinitiative in personal protective equipment capability development.

pro-The U.S Department of Homeland Security (DHS) Science and TechnologyDirectorate (S&T) launched a number of high-impact Apex programs in 2015.The Next Generation First Responder (NGFR) Apex program goal is for firstresponders to be protected, connected, and fully aware, enabling faster, moreefficient, and safer responses to a broad range of threats and disasters TheNGFR program is developing an integrated and modular ensemble thatincludes an enhanced duty uniform, personal protective equipment, wearablecomputing and sensors, and robust communication networks The NGFR willprovide an enhanced capability of responding with increased protection, com-munication, and situational awareness The integration of standards and testinginto the overall program is critical for delivering and sustaining this enhancedcapability to the first responder community

As mentioned earlier, the formal plan to implement the National Strategy forCBRNE Standards was not developed after the strategy was published The strategyhas been used in a number of activities to help structure standards developmentand testing for the deployment of specific capabilities The purpose of this paper is

to use the national strategy to frame the structure of the standards underpinning in

a specific scenario, integrating standards for the NGFR program The benefits ofthis discussion are three-fold: it helps to describe potential standards considerationsfor the NGFR, explores the utility of the national strategy, and provides recommen-dations for both efforts as they move forward

This document is not the standards development and integration plan for theNGFR Apex program; rather, it explores how the national strategy can be used toframe the discussion for addressing and integrating standards issues for a large,complex effort that relies heavily on standards

Goals of the National Strategy

The National Strategy for CBRNE Standards outlined the frameworkto establish astandards infrastructure to counter CBRNE threats that went beyond just develop-ing the technical standards The strategy established four basic elements in a devel-opment process for equipment standards The first step is to establish userrequirements The next step is converting those requirements into measureableperformance specifications and addressing interoperability considerations Thethird step is developing test methods or protocols that can be used by developersand multiple test facilities The fourth step is conducting test and evaluation usingthese protocols to verify critical performance parameters

This framework parallels in many ways the standards development process andincorporates operational concerns in the user requirements step The strategy alsorecognizes the need to go beyond the documentary standards process and toaddress the need for training and certification, testing infrastructure, responseplans, standard operating procedures (SOPs), and a forum for coordinating theseactivities on a wide scale These needs were expanded upon in the six goalsestablished by the strategy Each of the six goals will be expanded in terms of imple-menting a standards integration strategy for the NGFR program.

The Next Generation First Responder

The DHS S&T NGFR Apex program is designing new technologies and adaptingexisting capabilities to make responders better protected, connected, and fullyaware—thereby providing an enhanced capability to focus on their mission.Protected includes developing fire-, tear-, splash-, and biohazard-resistant dutyuniforms to protect responders from frequent hazards and providing physiologicaland environmental monitoring to help avoid threats and withstand those thatcannot be avoided Being connected includes fully interoperable and resilient com-munications equipment that reliably connects responders to the information theyneed, with universal open-source data standards to make information sharing easyand secure Being fully aware includes the use of integrated wearables, sensors, andremote monitoring to give the responder the right information at the right time,with situational awareness tools that provide mission-critical context even beforethey arrive on scene

This is a multiyear program that will provide increasing capabilities to theresponders over time It is a very technology intensive effort, and the integration ofstandards and testing are crucial to developing this enhanced capability for theresponder community There are a number of critical standards interests related tothe program The identification, integration, and development of performancestandards and test methods for enhanced fire, tear, splash, and biohazard protectionfor duty uniforms for a broad spectrum of responders is a critical component of the

“protected” aspect of the program This would also include the development andintegration of physiological and environmental monitoring performance standardsintegrated into a broad suite of protective equipment ensembles supporting a widerange of operational scenarios The “connected” aspect of the NGFR programincludes the integration of interoperable, resilient communications standardssupporting voice, data, and video transmission for multiple users in a wide range ofoperational scenarios Additionally, the identification and integration of standarddata formats and data standards are required to support the NGFR program To befully aware, performance standards, test methods, and conformity assessmentprotocols to integrate wearable sensors for multiple users in a wide range of opera-tional scenarios will need to be identified or developed The development of situa-tional awareness tool performance standards, test methods, and conformity

assessment protocols for multiple users in a wide range of operational scenariosalso supports being fully aware.

The NGFR program will make use of a wide range of existing standards, frommultiple technical committees in several standards development bodies In mostcases, the existing standards were developed for other uses or scenarios and mayneed modification to be fully incorporated into the NGFR program Additionally,with any new capability, new standards will be required to be developed Thestandards activities would need to support the transition to an increased level ofcapabilities deployed to the responder community

An Implementation of the National Strategy in

the Context of the Next Generation First

Responder

The following discussion examines the national strategy in terms of supporting thestandards development and integration aspects of the NGFR program Each of thegoals in the national strategy is further amplified by a number of key points expand-ing on the goal The goals of the national strategy and those supporting points aremodified and put in the context of the NGFR program as opposed to a nationalstrategy

GOAL 1: ESTABLISH AN INTEGRATED GROUP TO COORDINATE STANDARDS

AMONG STAKEHOLDER GROUPS

The objective of Goal 1, to establish a coordination body, in terms of implementing

a standards strategy for the NGFR program includes a number of factors This bodywould provide guidance and a framework for cooperation on standards identifica-tion, modification, development, and implementation among multiple stakeholdergroups such as various organizations involved in the development of the techno-logies, standards development, testing, user groups, and others This coordinationbody should be focused on integrating the standards to support the technologydevelopment and the transition to the responders It would provide guidance toend users on the capabilities and limitations of the equipment performance andinteroperability aspects This body would coordinate the identification of existingstandards, identify gaps in existing standards, and develop a plan for addressingthose gaps through either modifying existing standards or developing new ones.This would entail working with several different standards development bodies andtechnical committees within those standards bodies

This group would perform or coordinate recurring analyses to identify gaps incapabilities, standards, test methods, performance assessment, SOPs, and trainingand certification programs as additional capacities are added to the NGFR program

as it matures It would identify the needs for and coordinate the development of theneeded standards and testing infrastructure for the assessment of the new technolo-gies and capacities of the NGFR program because many aspects of it may not be

currently addressed in the existing standards and testing infrastructure This wouldaddress component and subcomponent testing but also full ensemble and inte-grated operational testing of the capability It would facilitate agreements amongfederal partners and other stakeholders to include agreements among various stand-ards development and testing organizations that may be adopting and integratingaspects of standards and test methods developed by other organizations into theenhanced capability of the NGFRprogram This could also include coordinationwith various standards development bodies to harmonize activities to avoid dupli-cative or conflicting standards development.

This group would also identify and take steps to address conflicts with laws orregulations regarding the implementation ofnew capabilities Finally, at a minimum,this body should consist of representatives from the activity driving the technologydevelopment, a higher level standards coordination function, and key stakeholders toensure the activity is meeting the users’ needs

GOAL 2: COORDINATE AND FACILITATE THE DEVELOPMENT OF EQUIPMENT PERFORMANCE STANDARDS AND PROMOTE THE USE OF THESE STANDARDSKey aspects of the objectives of Goal 2—promoting the development of per-formance standards in terms of implementing a standards strategy for theNGFRprogram—would include a number of factors One critical aspect isidentifying key performance parameters for the NGFRprogram in terms of lev-els of protection against the various threats and hazards (fire, liquid splash,biohazard, tear, etc.) for the ensemble as well as parameters for communica-tions, situational awareness, and physiological and environmental monitoring.These requirements most likely would evolve over time and would need to beaddressed in a timely fashion though development of performance standards.Key suitability factors such as reliability, availability, maintainability, affordabil-ity, interoperability, and manpower, personnel, and command and control inte-grations would need to be identified Other factors include survivability and safetyrequirements such as utility after exposure, ruggedness, decontamination, clean-ing, and reuse requirements

There would be a need to provide guidance regarding the capabilities and tations of the equipment to allow the purchasers and users of the equipment tomake informed decisions One consideration, however, when establishing perform-ance requirements, is to be aware of whether technology will be able to achievethese requirements or, if needed, to provide a structure to the standards and testmethods to support technological evolution Setting conflicting requirements in thestandards must be avoided, such as a material with a low thermal burden with highbreathability that must be able to withstand penetration from a high volume liquidhazard That combination is very difficult to attain One consideration is structuringthe performance standard with various levels or classes of capability that will allowtechnologies to enter the market at various points and not be artificially constrained

limi-by the structure of the standard

GOAL 3: COORDINATE AND FACILITATE THE DEVELOPMENT AND ADOPTION

OF INTEROPERABILITY STANDARDS

Key aspects ofthe objectives ofGoal 3, coordinating and facilitating the developmentand adoption of interoperability standards in terms of implementing a standardsstrategy for the NGFR program, would address a number of factors Interoperabilitystandards allow the systems to workwith other systems or products in the present orfuture without restricted access or implementation, communication, and data flowsamong critical nodes Interoperable systems do not interfere with or are adverselyimpacted by other systems Interoperability standards address either functionalcharacteristics, such as data output or format, or physical characteristics (e.g.,electrical or mechanical characteristics) to allow the exchange of information amongdevices, equipment, or systems

Interoperability considerations also include logistical issues such as batteries,power supplies, and the like, to minimize the logistical burden on agencies procur-ing the NGFR Understanding the implications and effects the projected operationalenvironment will have on the new capability is important Consider what is beingadded to the ensemble that then could be exposed to high thermal, liquid, or otherenvironments Human system integration and supporting standards such ascontrols, readouts, and interfaces (not only for the operator/user but for commandand control) need to be considered This would include the ability to rapidly andseamlessly integrate additional organizations into the networkfor a large-scaleincident, allowing for a multijurisdictional response and multiple responderdisciplines such as fire, emergency medical services, law enforcement, and tacticallaw enforcement

The security of the networkand communications, encryption, and cybersecurity issues needs to be considered and addressed The integration of aspects ofinteroperability and compatibility will serve to reduce costs and promote plug-and-play options, thereby reducing the complications associated with proprietary inter-faces and data formats

GOAL 4: PROMOTE ENDURING CHEMICAL, BIOLOGICAL, RADIOLOGICAL,

NUCLEAR, AND EXPLOSIVE STANDARD OPERATING PROCEDURES TO

SUPPORT PREPAREDNESS AND RESPONSE

Although it is beyond the scope of a given technology development program toformulate the SOPs and concepts of operation (CONOPS) for the users, the DHSNational Response Framework[2] is a high-level document that provides guidancefor communities for all levels of response However it is not at such a level where itwould address incorporating a capability such as the NGFR program It is criticalthat standardized SOPs be developed to optimize the capabilities delivered by theNGFR program, and that organizations are trained and aware of the capabilitiesand limitations provided by the technology The SOPs will facilitate coordinationamong organizations at all levels, which is especially critical during a large-scalemultiagency response The new SOPs should build upon existing SOPs, protocols,

and agreements, addressing the new capabilities related to procedures with whichthe users are already familiar and that they are trained to use.

GOAL 5: ESTABLISH VOLUNTARY TRAINING AND CERTIFICATION

STANDARDS AND PROMOTE POLICIES THAT FOSTER THEIR ADOPTIONTraining is critical to the successful deployment of any technology and capability.Training at all levels extends from the individual on the personal use of the equip-ment up to all levels of command and control The new capabilities provided by theNGFR program will require significant training at all levels There should be provi-sions for integrating or addressing the capabilities provided by the NGFR programinto the existing training and certification programs that are discipline-centeredand for all levels of users Provisions for the adoption and promulgation of criticalNGFR-related standards and protocols will be important to align with grantsprograms and to support mutual assistance among neighboring jurisdictions anddisciplines The new capabilities will require additional training and testing to gainappropriate levels of proficiency commensurate with a user’s mission requirements,skill level, and leadership responsibilities Significant training will be required forleadership and incident commanders to be able to optimize the information flow(both push and pull) to make appropriate and timely informed decisions and yetnot be overloaded with minute details

GOAL 6: ESTABLISH A TESTING AND EVALUATION INFRASTRUCTURE AND CAPABILITY TO SUPPORT CONFORMITY ASSESSMENT STANDARDS

There will be a need for the coordinating group mentioned in Goal 1 to serve as theforum to resolve issues unique to testing and evaluation (T&E) The technologiesdeveloped by the NGFR program will not immediately fit in the existing PPE testingand certification programs The current testing and certification programs arefocused on the ability of the PPE to protect the user from defined hazards (e.g.,flame, chemical, biological threats, cut, puncture, ballistic threats) and on the dura-bility of the PPE in terms of various operational environments and scenarios Theintegration of wearable sensors, the communications and data infrastructure, andthe other requirements being addressed through the NGFR program will need addi-tional T&E infrastructure and protocols

Standardized terminology and definitions will need to be established so that theparameters of the NGFR program are understood not only by the R&D communitybut also by the standards developers, testing and certification community, and theusers, trainers, and policy developers Open, transparent, and reproducible test meth-ods, which could be conducted at multiple sites through multiple venues, will need to

be identified to support the testing New reference materials and data may need to bedeveloped to support a broad range of users and testing organizations Additionally,considerations for the accreditation of testing facilities and certification bodies should

be discussed, and the capabilities of the existing infrastructure to test and certifyNGFR technologies prior to transition to the user communities should be examined

Early open dialog with key testing and certification stakeholders is critical to avertcomplications as technologies are ready for commercialization The ability ofindependent testing and certification of products developed to become agreed-uponperformance standards, capitalizing on the existing infrastructure, will help ensure areliable product is procured and used by the response community.

Beyond the National Strategy

Another way of considering timing of standardization for new technologies orcapabilities—particularly in addressing the spectrum of standardization activities toassist with development, deployment, and operations and support—was outlined byEgyedi and Sherif in terms of the technology S-curve [3] Their paper discussed thetiming of standards in three time phased areas called anticipatory standards,enabling standards, and responsive standards

Anticipatory standards are those that need to be established early in theproduction of the capability In the case of the NGFR program, this could be identi-fying the key health and safety requirements, critical interoperability concerns, andsupporting metrology and test method development to verify that critical perform-ance parameters are met The second group—enabling standards—refines andimproves the standardizations of the capability In terms of the NGFR program,these would be the performance standards, test and evaluation protocols, and theconformity assessment program that would support the transition of the technology

to the users These standards, in conjunction with appropriate guidance, training,and information on how to effectively integrate this new capability to the user, arecritical for the transition and sustainment of the capability once deployed

The third group, responsive standards, is deals with the manifestation of thetechnology and how it relates to a specific service environment or to the extensions

of the applications to new services In the context of the NGFR program, thesewould be further modifications of the standards to account for addressing newrequirements, lessons learned, periodic updates to the existing standards throughthe respective standards bodies’ policies, and the like This activity usually occursbeyond the development program, and it needs to be carefully monitored to ensurethat the standards and deployed technologies do not diverge over time to such anextent that they could impact the health and safety of the user or impact theperformance of the capability

Some areas are not specifically called out in the strategy; however, the strategywas not an all-encompassing document Such areas as human system integrationare particularly critical in a project such as the NGFR program, and cyber securityissues are much more tangible concerns that must be integrated into connectedsystems such as the NGFR program.

There are other aspects to an integrated strategic standardization managementapproach that are not fully covered in the strategy In the NGFR program,technology standards for sensors and communications, data, and networking aremerged with more conventional personal protective equipment standards that aremore material- and design-based Additionally, placing the sensors and newtechnologies in very harsh environments and operating conditions needs to be fullyaddressed in the standards The current in situ personal protective equipmenttesting and certification infrastructure would need to adapt to accompany theseemerging requirements

The strategy does a very good job of considering the aspects of deliveringstandards-based capability from user requirements through testing, training, andCONOPS to the user In other words, for a discrete program (from requirements totransition of the capability), the strategy does a very good job of highlighting thecritical aspects of standardization issues Other factors, as discussed earlier, should

be addressed to integrate and synchronize standards for a complex, evolving, tive such as the NGFR program

initia-References

[1] National Science and Technology Council, Committee on Homeland and National rity, Subcommittee on Standards, A National Strategy for CBRNE Standards, Office of Science and Technology Policy, Washington, DC, 2011.

Secu-[2] Federal Emergency Management Agency, National Response Framework, 2nd Ed., Department of Homeland Security, Washington, DC, 2013.

[3] Egyedi, T M and Sherif, M H., “Standards’ Dynamics Through an Innovation Lens: Next Generation Ethernet Networks,” Proceedings of the First ITU-T Kaleidoscope Academic Conference, “ Innovations in NGN ,” Geneva, May, 12–13, 2008, IEEE Communications Society, pp 127–134, doi:10.1109/KINGN.2008.4542258

Margaret Auerbach,1Thomas Godfrey,1Michael Grady,1

and Margaret Roylance1

Assessing Design and Materials

for Flame-Resistant Garments

Citation

Auerbach, M., Godfrey, T., Grady, M., and Roylance, M., “Assessing Design and Materials for Flame-Resistant Garments,” Performance of Protective Clothing and Equipment: 10th Volume, Risk Reduction Through Research and Testing, ASTM STP1593, B Shiels and K Lehtonen, Eds., ASTM International, West Conshohocken, PA, 2016, pp 11–26, doi:10.1520/STP159320160006 2

ABSTRACT

Flame and thermal protective garments can be produced by the use of materialsthat are either inherently flame-resistant (FR) or rendered FR by inclusion of FRadditives, but the selection of FR materials cannot ensure FR protection.Fasteners such as zippers or hook and loop closures are often not FR, andinclusion of these design elements can induce burn injury in an ensemble if agarment is exposed to a flame or thermal threat To maximize performance of an

FR garment, the materials and design must work together This paper reportsresults of FR testing of various military garments and demonstrates theimportance of integrating FR textiles and design features that work together toprovide optimal protection against flame and thermal threats It also addressesthe advantages of a novel midscale FR test that is under development A greatdeal of useful information is lost when standard FR test methods are utilized If

FR tests are to be used effectively to refine design details and minimize potentialburn injury, an alternate method providing more detailed information about thenature and local surface distribution of the potential burn injury is required Themidscale method under development provides a more sensor-rich environmentthan do those of standard test methods It also accommodates alternatemethods of data acquisition and reduction and burn injury prediction The newtest lies between swatch and ensemble level and uses propane torches as the

Manuscript received January 15, 2016; accepted for publication April 8, 2016.

1 U.S Army Natick Soldier Research, Development and Engineering Center, General Greene Ave., Natick, MA 01760

2 ASTM Tenth Symposium on Performance of Protective Clothing and Equipment: Risk Reduction Through

Research and Testing on January 28–29, 2016 in San Antonio, TX.

Copyright V 2016 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.

STP 1593, 2016 / available online at www astm org / doi: 10 1520/STP159320160006

heat source to provide a heat flux of 84 KW/m2 The midscale apparatus can also

be used for more realistic sensor calibration

Keywords

garment design for protection, midscale flame-resistant (FR) testing, transmitted heat flux measurement, burn injury modeling

Introduction

NEED FOR FLAME-RESISTANT PROTECTION

In the past, the army has provided flame-resistant (FR) garments to mountedsoldiers and others who might expect to encounter a flame or thermal threat in thecourse of their customary duties In the current asymmetric battlefield, however,flame and thermal protection has become increasingly important to all warfightersdue to the prevalence of improvised explosive devices and other incendiaryweapons [1] The army has therefore taken action to provide FR garments to alldeployed warfighters with the introduction of the FR Army Combat Uniform(ACU) The Defender M fabric used in the FR ACU is a ripstop fabric blend of

65 % FR rayon, 25 % para-aramid, and 10 % nylon [2] All other dismountedsoldiers are issued the standard ACU that uses a wind-resistant poplin 50/50 nylon/cotton blend [3]

The addition of phosphorus-containing compounds during fiber spinningenhances the resistance to combustion of cellulose-based rayon, producing so-called FR rayon fiber Further improvement in FR properties can be achieved byblending FR rayon with other fibers, as in the Defender M fabric Thermal decom-position of FR rayon in the blended FR ACU fabric [4] differs from its behavioralone, in part because nitrogen produced by combustion of the 10 % nylon provides

a synergistic effect with the FR phosphorus additive in the rayon Enhanced ring of the rayon and improved effectiveness of the phosphorus flame retardant[5,6] is observed in the blended fabric

char-When FR rayon and nylon fibers are further blended with para-aramid, which

is an inherently FR material, the resulting fabric exhibits excellent FR properties.Although the phosphorus additive is depleted from the FR rayon in Defender Mfabric during combustion, leading to an eventual decrease in flame and thermalprotection, the Defender M fabric in the FR ACU exhibits much improved FRperformance over the nylon/cotton in the ACU as measured by ASTM D6413,Standard Test Method for Flame Resistance ofTextiles (Vertical Test), or the verticalflame test method

TYPES OF FLAME-RESISTANT TESTING

There are two primary types of test methods used to characterize the response of

a material or end item to a flame and thermal threat These are commonly called

FR tests The first type of FR testing measures the resistance to combustion in the

presence of an ignition source Among the most common of these is theASTMD6413 vertical flame test method mentioned earlier In ASTM D6413, theedge of a swatch of material is exposed to a point ignition source for 12 s andthe subsequent flame spread is monitored The FR ACU material exhibits a 2-safter-flame as measured using ASTMD6413, compared to more than 30 s after-flame as measured by the same method for the ACU fabric As these results indi-cate, the FR ACU is self-extinguishing, but the ACU is not.

The second type of FR testing measures another important element of textileflame and thermal protection, the extent to which the fabric prevents transmittedheat flux from reaching the skin Even if the textile is self-extinguishing, burn injurycan occur due to heat transmitted to the skin through the fabric during a fire andeven after the fire has been extinguished Several test methods are available to mea-sure the transmitted heat flux through a textile material and to predict the extent

of resulting burn injury These methods range from swatch to ensemble level

An example of swatch level testing is the Thermal Protection Performance (TPP)test in which a fabric sample is subjected to a constant combination of 50 % radiantheat and 50 % convective heat The best known full-scale test is ASTM F1930,Standard Test Method for Evaluation of Flame Resistant Clothing for ProtectionAgainst Fire Simulations Using an Instrumented Manikin, or the standing manne-quin test in which a mannequin 1.85 m in height is instrumented with a minimum

of 100 heat sensors and exposed to a simulated fire condition using propanetorches

Previous interlaboratory testing has shown that the lab-to-lab variability in theASTM F1930 test and in the parallel International Organization for Standardiza-tion’s ISO 13506-1 is very high, although the extent of variability depends upon thetype of material in the garment being tested As stated in the precision and biasstatement in ASTMF1930-15 [7], the reproducibility limit from lab to lab is higherthan 50 % for some garments Some of this variability reflects the time-dependentnature of the depletion of FR additives in materials such as FR cotton and rayoncoupled with imprecise control of burn duration, but lab-to-lab variation in thetype of sensor and sensor calibration method used have also been identified aspossible sources An ISO project group, PG13506-01, is currently working to iden-tify and minimize the sources of variability in the ISO standard

Assessment of Performance

MEASUREMENT OF TRANSMITTED HEAT FLUX

To assess the thermal protection provided by a flame-resistant fabric or a completegarment, it is necessary to quantify the thermal energy that would likely be trans-ferred to the wearer’s skin if the wearer were exposed to a specific thermal or flamehazard environment The quantity of interest is the rate of energy transfer per unitarea of skin (i.e., heat flux), using units of either W/m2or cal/cm2-s, measured overthe period of time from the beginning of the exposure until thermal energy stored

in the garment is dissipated or transferred to the test form A test form or quin serves as a stand-in for the human form; the form is instrumented withsensors that are used to measure the heat flux transmitted through the protectivegarment In the design and materials of the test form and sensors, the intention is

manne-to approximate, as closely as practicable, the thermal inertia of the human skin,

so that surface temperatures on the test form are close to those that would occur

on a human and so that the test properly simulates heat transfer among skin,garment, heat source, and ambient environment

In North American laboratories, three different types of sensors are currently

in use: copper slug calorimeters, embedded thermocouples, and surface-mountedthermocouple sensors These sensor types are described in a recent review by Songand Mandel [8]; comparative testing of sample sensors of each variety has beenreported by Barker et al [9] Each sensor type has its strengths and weaknesses; thetesting community has not reached a consensus on a preferred design

It is noteworthy that progress continues to be made in improving sensor designand fabrication techniques; some problems seen in earlier models of sensors [8,9]have been largely mitigated The embedded and surface-mounted thermocouplesensors operate on a similar principle The heat flux absorbed at the sensor face isconducted along the axis of the sensor; the heat flux is determined from the temper-ature measurement using a model for one-dimensional heat conduction in a slabwith the thermophysical properties of the sensor body material This calculation isstraightforward for the surface-mounted thermocouple sensor, where Duhamel’smethod is used However, for the embedded thermocouple sensor, a techniquebased on methods of inverse heat conduction is required The copper slug calorime-ter is based on the notion that the rate of energy transfer into the slug, via theexposed face, can be calculated directly from the slug’s rate of temperature change,determined from a thermocouple mounted on the slug’s back face, assuming auniform temperature in the copper slug body The sides and back of the slug areinsulated to minimize thermal losses, which must be estimated empirically andincluded in the energy balance for accurate heat flux results

The sensors have two important functions in flame engulfment tests: to brate the so-called nude exposure conditions and to measure transmitted heat fluxbehind the garment For nude calibration burns, the test is run without a garment

cali-in place to measure the exposure heat flux and to verify that the exposure meetsrequirements for average values and distribution uniformity For a typical 4-s nomi-nal 84-kW/m2exposure, some sensors may see extreme heat fluxes well in excess of

120 kW/m2 Therefore, it is necessary for sensors to survive and measure intenseheat fluxes of several seconds in duration During actual garment testing, thesensors are required to accurately measure transmitted heat fluxes that may peak inthe tens of kW/m2 and then drop off to slightly negative values as the test formand garment cool over a period of a minute or so Typically, 90 s or so of heatflux data is used from each sensor in testing single-layer garments The datamust be free from offsets or unphysical artifacts that affect follow-on burn injury

predictions It is a difficult challenge for inexpensive, durable sensors to performboth of these functions well.

LIMITATIONS OF CURRENT BURN INJURY PREDICTION METHODOLOGY

In all the transmitted heat flux tests, prediction of burn injury depends uponmeasuring the transmitted heat flux time series data, then utilizing a mathematicalmodel of the three layers of the human skin to calculate predicted depth of burn as

a result of the incident heat flux In the standing mannequin test, the predicteddepth of burn at each of the sensors is ascribed to a percentage of the body surfacerepresented by that individual sensor This depth of burn is then binned as negligi-ble, second-degree, or third-degree burn The results are reported as predictedpercent of the total body surface experiencing second- or third-degree burns It isworth noting that the burn injury model used in ASTMF1930is validated against

a very limited number of actual human burn injuries, all of which were superficialsecond-degree burns

It is important to note that the use of the mechanical sensors previouslydescribed on test forms and mannequins leads generally to only a very sparse sam-pling of the transmitted heat flux acting over the protected body surface In themannequin test, for example, 123 mechanical sensors may be distributed—roughlyequally—over the body surface, excluding the hands and feet The responsive ele-ment in each copper slug sensor is 1.27 cm in diameter, and as such, the devicemeasures heat flux over a very small element of the mannequin surface (i.e., thearea of the copper disk, 1.267 by 10?4m2) In fact, though a large number of sen-sors is utilized, a comparison of the total sensor area with typical numbers for bodysurface area (BSA), 1.62 m2—excluding hands and feet, reveals that the sensors aresampling a little less than 1 % of the mannequin’s surface

In practice, the data from each sensor are assumed to represent the averageconditions in a relatively large region of skin; the body surface area predictedburned from each sensor location is adjusted based on the surface area that parti-cular sensor is taken to represent In the simplest method, sensor distribution isassumed perfectly uniform, and the burn prediction of each sensor is allocated as

100 % BSA/123 sensors ¼ 0.813 % BSA per sensor In garment tests, however,design features vary with position, and the response of the garment is not uniformover the large surface areas in between sensor locations Therefore, there are local-ized effects that are not detected in the response of the sparse sensor array

Unfortunately, a significant amount of detailed information about the natureand local surface distribution of the potential burn injury in the ASTMF1930test islost by distributing sensors Therefore, they are able to sample only a small portion

of the mannequin surface and to bin predicted depth of burn into only three levels

of injury Another limitation in the way ASTM F1930 is used in practice is thelack of visual observation in reporting the performance of design elements, inde-pendent of sensor data, especially if a critical design detail does not happen to lieover one of the widely spaced heat flux sensors This requires a careful examination

of the garment after the test is complete, preferably both before and after the ment has been removed from the mannequin.

gar-Given the limitations of the ASTMF1930 test and the burn injury ogy, the most effective approach to refining garment design details and minimizingpotential burn injury lies in an approach that goes beyond simply reportingpredicted percent body burn This prediction is calculated from data on widelyseparated sensors using a model that does not take into account variation in theskin physiology across the surface of the body The ASTM F1930 test should beused in conjunction with a method that can provide richer information on potentialinjury associated with failure of those design details A midscale test lying betweenswatch and ensemble level testing that uses propane torches as the heat source hasbeen developed and has been used to provide that additional data

methodol-Use of the Midscale Test to Predict Burn Injury Details

The midscale test apparatus is a flexible system that allows the use of a family oftest forms, including instrumented flat plates and cylinders—and even head andhand forms, for testing helmets, balaclavas, and gloves This setup allows testing ofmaterials and design details in a flame environment comparable to that found inthe ASTMF1930test without the effort and cost of fabricating an entire ensemblefor each test The smaller area of the midscale test compared to the mannequinallows greater control of the standard target value of 84 kW/m2heat flux and muchhigher density of sensors per unit surface area One of the most detailed descrip-tions of the apparatus and test method may be found in a report on the use of themidscale test to assess the thermal response of ultrahigh molecular weight polyeth-ylene materials in a flash flame environment [10]

The midscale test is conducted with the same basic test setup as theASTMF1930instrumented mannequin test, using propane burners in conjunctionwith a midscale test form A diagram of the midscale test setup (with the cylinder)

is shown inFig 1

The fire is controlled by simultaneously opening a solenoid valve for eachburner The duration of opening is set with an electronic timer The data acqui-sition system records data from each of the heat flux sensors at a sampling rate

of 5 Hz

The heat flux on the midscale test apparatus (cylinder or flat plate) is calibrated

to within 65 % of the target 84 kw/m2by adjusting the standoff and positioning

of the burner flame Propane is supplied to the burners at 50 psi (3.45 by 10?5Pa)through a 3/32-in (2.38 mm) orifice in each burner

The flat panel midscale test requires a 20-in.2sheet of material that is clampedaround the 13-in.2test panel, as shown inFig 2a The flat panel apparatus used inthis testing has an array of 13 sensors arranged around the center of the panel asshown inFig 2b

The detailed information that can be provided by an array like the one shown

in Fig 2 is much more useful in assessing the potential nature of the local burninjury that would occur when a design detail such as a pocket, zipper, or otherclosure ignites in a fire Although percent body burn clearly is no longer a usefulconcept, the same burn injury model used for the ASTMF1930 can be utilized topredict depth of burn from the transmitted heat flux at each sensor in the midscalesensor array

Effects of Design Features and Additional Gear

on Burn Injury

As mentioned earlier, in some cases, visual observation of the garment/systemperformance during ASTMF1930has far greater value than the numerical value oftotal predicted body burn.Design features and additional gear can play a key role

in determining the actual protection provided by an end item or garment.Thesefactors may appear minor and are often not reflected in the value of total predictedbody burn but, if addressed, they can result in significantly increased protectionfor the wearer that might allow a soldier to perform his/her mission successfully.There are even situations in which increased protection during fire exposure can

be designed into the garment or achieved by the way the garment is worn, and

FR materials may not be required

FAILURE OF CRITICAL SYSTEM DETAILS

The power of careful visual observation of a garment system before and afterASTM F1930 testing in conjunction with detailed midscale assessment of criticaldesign details was demonstrated in a series of tests conducted for the U.S Air Force

in which a system was being tested to obtain a “safe-to-fly” designation.This testing

is illustrated in Fig 3.The system was required to pass a specified value of totalpredicted body burn.The system met the requirement, but visual observationindicated that one of the pockets located on the vest was almost entirely gone aftertesting.This general purpose pocket typically carries navigational equipment thatneeds to be secured in the event of an emergency situation

The initial ASTMF1930test in conjunction with the observation of the pocketfailure indicated that the vest would not perform as required in a fire.An initialredesign demonstrated that the pocket performance could be improved.A series ofmore robust pocket designs (shown inFig 4) were then tested in the midscale testsystem to demonstrate their performance and to assess the burn injury that mightoccur during a flame scenario.One of the pocket redesigns was selected, and thefull system with the modified pocket design was then declared safe-to-fly.Therewas no measurable difference between the initial and final vest design in predictedpercent body burn based on the ASTM F1930 test, but one clearly met missionrequirements while the other did not

THE EFFECT OF DETAIL LOCATION

As discussed here, the sensors in the ASTMF1930mannequin only sample a littleless than 1 % of the mannequin’s surface.Sometimes problematic design elements orsystem components happen to be located at a sensor location and transmitted heatflux will indicate a predicted burn injury at that location.More frequently, designelements or components do not lie directly over a sensor, and there is no indication

of a problem in the burn injury prediction.In such a situation, possible burn injurymay be missed based on the ASTMF1930predicted body burn alone

In one case, a third-degree burn was predicted at an isolated sensor locationduring ASTMF1930testing of a vest.Visual inspection of the garment after testing,but before it was removed from the mannequin, revealed that a small metal equip-ment hook (shown inFig 5) was situated at that sensor location and was transfer-ring heat energy to the mannequin, resulting in the predicted third-degree burn.

If the hook had been located an inch or two further from the sensor, thispredicted injury would have gone undetected and an easily preventable burn injurycaused by the hook might have resulted.If the visual inspection of the garment hadbeen done after the vest was removed from the mannequin (especially if the gar-ment was cut from the mannequin), the link between the hook and the injury might

testing—vest pocket almost completely destroyed without affecting

ASTM F1930 -predicted percentage of burn injury (top) Originalpocket

design (bottom left) Initial pocket redesign (bottom right).

also have been missed Instead, additional padding was provided behind the hookand potential burn injury was prevented.

Another example of the ASTMF1930test not telling the full story of FR tion occurred during the testing of prototype combat shirts designed to providemoisture management under ballistic vests Visual observation indicated that thenylon zippers located down the upper quarter of the center front were melting tothe mannequin’s surface Because there were no sensors located on the mannequin

protec-in this area to measure the transmitted heat energy, the meltprotec-ing of the zipper wasnot measured or reflected in the predicted burn injury By redesigning the zipperplacket area by encasing the zipper tape and teeth in the garment’s FR material,providing a zipper facing (a layer or two of fabric between the zipper and skin),

or both, the melting to the mannequin and likely burn injury to the wearer ofthe shirtwas resolved This was a relatively simple solution to prevent a possible burn injury

design was declared “safe-to-fly.”

In fact, the redesigned placket facing now also includes padding to provide increasedcomfort to the soldier.Fig 6shows the initial and final zipper design.

FILTERING

In some instances, filtering can be used in conjunction with standard ASTMF1930

testing to predict the effect of individual materials, design elements, or equipment

on burn injury Filtering is the blocking of information from selected sensors beforepredicted burn injury is calculated The use of filters, although not a substitute foractual testing, can provide valuable information for developing new items anddesigns in a more cost-efficient and timely manner

For example, 12 garments from different manufacturers—each using a differentcombination of a jersey shirt fabric with a woven trouser fabric—were evaluated forthe U.S Marine Corps Burn injury for each individual ensemble was predictedusing ASTMF1930testing The percentage of body burn was then predicted for fil-tered data from the knit and woven parts of the garment separately The burn injurypredictions from this study are shown inFig 7

InFig 7, the total predicted body burn from each of the 12 garments is sented as a separate bar Predictions of the percentage burn under the knit andwoven portions of each garment were then calculated This allowed a direct com-parison of the performance of each individual fabric in addition to the garment.The overall predicted performance of Garment 7 as represented by the seventh bar

repre-in the Total Ensemble graph repre-inFig 7is superior to the others tested, but the filteredresults suggest that the best garment might combine the knit fabric used inGarment 5 (the fifth bar in the Knit Fabric graph inFig 7) with the woven fabricused in Garment 7 (the seventh bar in the Woven Fabric graph inFig 7)

Filters can also be used to assess the possible impact of equipment on the burninjury predictions In one study, a filter was created by mapping out the sensors

on the ASTMF1930 mannequin under the Scalable Plate Carrier (SPC), a type ofballistic plate carrier Total body burn was predicted from an ASTMF1930test on

zipper design at left Modified zipper design at right.

a soldier ensemble without the SPC The predicted burn injury for the system wasthen recalculated without the filtered sensors Finally, an ASTM F1930 test wascarried out on an ensemble with the SPC Results are shown inFig 8.

The results in Fig 8 show the location on the mannequin of predicted first-,second-, and third-degree burns for each of the three test conditions The location

of a sensor predicting a third-degree burn is shown in red, a second-degree burn is

Left: ASTM F1930 control results Middle: ASTM F1930 filtered results Right: ASTM F1930 with SPC.

shown in yellow, a first-degree burn is shown in green, and no burn is shown indark blue The location of filtered sensors is shown in light blue The numericalvalues for predicted percent of body burn for each condition are shown inTable 1.

The filtered result predicted a higher percentage of burn injury than theensemble tested with an actual plate carrier, representing a worst-case scenario.Although some effects of the presence of the plate carrier are not captured usingthis approach, this assessment is a good indication of the protection provided bythe presence of the plate carrier and the ballistic plates This is accomplished with-out actually damaging a ballistic protective system Although it is not recommendedthat analysis of filtered data be used in place of actual testing, it can be a potentiallyvaluable tool for predicting the impact of new garment designs, fabrics, or equip-ment relatively quickly and inexpensively

OTHER FACTORS THAT AFFECT FLAME-RESISTANT PROTECTION

Design elements that may affect FR protection include uneven fabric layering orsudden increases in fabric thicknesses These should be avoided because theytypically result in flame travel along this detail Flames also tend to run alongstraight-edge pocket flaps but not along angular pocket flap edges Ballistic vestsand plate carriers provide additional FR protection and do not themselves increasepredicted burn injury However, when testing with hard plates in place, additionaldamage may occur to the bottom edge of the fabric holding the plates in placeand this region of the fabric might ignite Pleated pockets that are not tacked downmay also catch fire These design details may not affect the total predicted bodyburn in a 4 s ASTM F1930test, but they are a potential source of burn injury andmay be eliminated through smarter design choices

The way a garment is worn can also strongly affect the FR protection itprovides In a two-piece ensemble, tucking the shirt into the pants as opposed

to leaving the shirt untucked provides significantly increased FR protection tothe wearer Leaving the shirt untucked can result in the shirt tails and even anundergarment catching fire because the loose shirt can cause a chimney effect.Fortunately, wearing a garment such as a vest over an untucked shirt holds thegarment close to the body and can prevent flames from catching undergarments

1930 without SPC 1930 with SPC Filter 1930 with SPC

Burn Injury Prediction Burn Injury Prediction Burn Injury Prediction

No Burn: 54.45 % No Burn: 65.98 % No Burn: 76.92 %

1st Degree 0.88 % 1st Degree 0.88 % 1st Degree 0.88 %

2nd Degree 25.72 % 2nd Degree 16.49 % 2nd Degree 12.32 %

3rd Degree 18.84 % 3rd Degree 16.53 % 3rd Degree 9.77 %

Total (2nd and 3rd) 44.56 % Total (2nd and 3rd) 33.02 % Total (2nd and 3rd) 22.09 %

An equipment harness worn over an untucked shirt can also reduce the likelihood

of an undershirt catching fire Clothing systems that are not intended to provideany FR protection exhibit significantly increased protection in the ASTMF1930testwhen the shirt is tucked in

Data demonstrating the effect of tucking in the shirt are shown inTable 2for

a series of garments with varying levels of FR protection (Note that predictions

in Table 2 include 7 % third-degree burns in the unprotected head area.) Eventesting performed on a 100 % nylon clothing system shows some improvement

in predicted body burn when the shirt is tucked in This is despite the fact thatthe garment was fully engulfed in flame during the test Tests on the nylon gar-ment were conducted with two types of undergarments that provided additionalprotection in the torso area It should be noted that the extent of the predictedbody burn dropped by more than 70 % when this highly flammable garment wasworn with the shirt tucked in and with a Nomex long-sleeved undershirt anddrawers

Table 2shows that non-FR garments made of 50 %/50 % NyCo exhibit almost

50 % lower burn injury prediction when tested with the shirt tucked in TheASTM F1930NyCo testing was performed without any underwear, and this mayhave contributed in part to the large increase in protection observed when the shirt

is tucked in The benefit of wearing a shirt tucked in is still observed in performance

of FR ensembles such as the one using the Nomex/NyCo blend, but the extent ofthe improvement is smaller

In addition to close visual observation of a garment after ASTMF1930testing,the functionality of garments and components after exposure should also beassessed If the garment contains a zipper that allows the garment to be donnedand doffed and the zipper is not functioning after testing, this creates a potential

Predicted Body Burn 2nd degree 3rd degree Total

100 % Nylon *

Untucked—underwear—FR S/S (modacrylic blend) undershirt 42.86 22.28 65.14 Tucked—underwear—FR S/S (modacrylic blend) undershirt 33.36 27.31 60.67 Tucked—underwear—FR L/S (Nomex blend) undershirt and drawers 8.41 9.88 18.29

50 % Nylon/50 % Cotton (Design 1) *

* Testing terminated, garment extinguished.

problem that could have major impact on the functionality of the garment.Any stiffness or brittleness of the fabric should also be noted when removing a gar-ment from the mannequin A fabric embrittled by fire damage is more likely tobreak open as a result of the movement required to escape a fire The stationarystanding mannequin test does not provide any information about the effect ofmotion on the integrity of the fabric Dye sublimation, colorfastness, and heatshrinkage of test garments are also important visual observations.

The fit of a garment is one of the most important factors that affects F R tion and possibly the most difficult to predict or explain The ASTM F1930 testmethod states that a larger garment size will yield lower burn injury, but loosegarments can create a chimney effect that in turn can result in higher burn injurypredictions Tight-fitting garments or fabrics that exhibit heat shrinkage duringtesting can hold heat closer to the body, resulting in higher burn injury predictions.The effect of fit may therefore be counterintuitive and difficult to predict

protec-Conclusions

In conclusion, the use of FR materials in a garment can enhance the degree of FRprotection provided to the wearer, but the selection of FR materials alone cannotprevent burn injury It is important when conducting ASTMF1930testing to lookbeyond the total predicted body burn commonly reported Design details such

as zippers, hook and loop closures, patches, or additional gear such as hooks aretypically not FR and are often overlooked when designing FR garments If carefulvisual observation is utilized both before and after the garment is removed from themannequin, failure of these components can be discovered

Valuable detailed information about the nature and local surface distribution ofthe potential burn injury in the ASTMF1930test is lost by binning predicted depth

of burn into only three levels of injury and further by distributing sensors so theyare able to sample only a small portion of the mannequin surface If FR tests are to

be used effectively to refine design details and to minimize potential burn injury, analternate method providing more detailed information about the nature and localsurface distribution of the potential burn injury is required The midscale methoddescribed here lies between swatch and ensemble level, and it uses propane torches

as the heat source to provide a heat flux of 84 KW/m2, the same conditions used inthe full-scale ASTMF1930 This method provides a more sensor-rich environmentthan standard test methods and also accommodates alternate methods of dataacquisition and reduction and burn injury prediction The use of the ASTMF1930

ensemble test in conjunction with the midscale method for clarifying details oftransmitted heat flux and predicted burn injury provides a fruitful approach foridentifying potential sources of injury This frequently allows the development ofmore suitable, low-cost alternatives to ensure the integrity of the garment and toprovide better protection based on its intended use

[1] Wilusz, E., Ed., Military Textiles, CRC Press, Boca Raton, FL, 2008.

[2] TenCate Protective Fabrics, TenCate Defender M, Data Sheet, Royal Ten Cate, Javatoren, Netherlands, 2014, http://tencatefrfabrics.com/wp-content/uploads/2014/07/Data- Sheet-Defender-M-Woven.pdf (accessed January 14, 2016).

[3] MIL-DTL-44436B, Detail Specification, Cloth, Wind Resistant Poplin, Nylon/Cotton Blend, U.S Department of Defense, Washington, DC, 2012.

[4] Yip, P., “Characterization of Flame Retardant Military Fabrics and Industrial Textile Fibers

by Simultaneous DSC-TGA, and Pyrolysis GC-MS,” Proceedings of the 23rd Annual Conference on Recent Advances in Flame Retardancy of Polymeric Materials, Stamford, Connecticut, May 21–23, 2012, BCC Research, Wellesley, MA, pp 35–51.

[5] Godfrey, L E., “Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) Studies of Flame-Retardant Rayon Fibers,” Textile Research Journal , Vol 40,

[8] Mandal, S and Song, G., “Thermal Sensors for Performance Evaluation of Protective Clothing Against Heat and Fire: A Review,” Textile Research Journal , Vol 85, No 1, 2015,

pp 101–112.

[9] Barker, R L., Harmouda, H., Shalev, I., and Johnson, J., “Review and Evaluation of Thermal Sensors for Use in Testing Firefighters Protective Clothing,” Technical Report NIST GCR 99-773, National Institute of Standards and Technology, Gaithersburg,

MD, 1999.

[10] Fitek, J., Auerbach, M., Godfrey, T., Grady, M., and Proulx, G., “Thermal Response of Ultra-High Molecular Weight Polyethylene (UHMWPE) Materials in a Flash Flame Environment,” Natick Technical Report TR-15/005, Army Natick Soldier Research, Development and Engineering Center, Natick, MA, 2014.

Hugh Hoagland,1Stacy L Klausing,1and Jill A Kirby1

Theories from Evaluation: How

Arc Flash Protective Fabrics Work

to Protect in the Hazard

Citation

Hoagland, H., Klausing, S L., and Kirby, J A., “Theories from Evaluation:How Arc Flash Protective Fabrics Work to Protect in the Hazard,” Performance of Protective Clothing and Equipment: 10th Volume, Risk Reduction Through Research and Testing, ASTM STP1593,

B Shiels and K Lehtonen, Eds., ASTM International, West Conshohocken, PA, 2016, pp 27–41, doi:10.1520/STP159320160020 2

ABSTRACT

Material responses in an actual arc event differ based on many variables in theevent itself, but fiber content and construction of the fabric result in substantialdifferences in testing using the ASTM F1959fabric test method and the ASTMF2675 glove test method The objective of this review was to understand howfabrics protectively react to an arc event from a scientific perspective to assist

in personal protective equipment development, research, and understanding inaccident investigations This paper explores the five major ways a flame-resistantfabric works to protect the end user in an arc:carbonization, ablation, insulation,isolation of plasma/current flow by fabric, and isolation by air gap

Keywords

electric arc protection, arc flash clothing, arc flash fibers, arc flash protection,

ablation, carbonization, isolation

Introduction

In order to discuss how fabrics work to protect in arc flash, we must first define anarc flash event An arc flash can be defined as an electrical breakdown of gas that

Manuscript received January 27, 2016; accepted for publication April 11, 2016.

1 ArcWear, 3018 Eastpoint Pkwy., Louisville, KY 40223

2 ASTM Tenth Symposium on Performance of Protective Clothing and Equipment: Risk Reduction Through

Research and Testing on January 28–29, 2016 in San Antonio, TX.

Copyright V 2016 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.

STP 1593, 2016 / available online at www astm org / doi: 10 1520/STP159320160020

produces an ongoing plasma discharge, resulting from current flowing through anormally nonconductive media, such as air The plasma temperatures in an arc canreach 35,000?F in the core of the plasma, but these plasma roots typically do notreach a worker Typical temperatures in an arc flash are closer to 500–2,000?F, buttotal energy is more critical because there is a strong infrared component and

a convective component in the arc In real events, fatal burns can occur at distancesover 10 ft [1] Arc flashes are powerful explosions that can have a heat fluxexceeding 50–100 cal/cm2/s Testing in accordance with the ASTMF1959standardstates that it uses a range of 2–600 cal/cm2/s, but this is not possible in the testmethod without changing parameters of distance [2] The actual energy is close to

50 cal/cm2/s because a 2-s exposure in the standard test setup produces 100 cal/cm2/s.Not only is there a thermal hazard when exposed to an arc flash, but protection isrequired from the potential additional hazards of molten metal and plasma Thereare five known types of arc exposures: open-air, box, tracking, ejected arc, andrunning arc (boxed is more common in low voltage (LV) < 600V applications, andtracking, open-air, and running arcs are more common in high voltage (HV) > 600Vapplications) [3,4]

To protect from the arc flash hazard, arc-rated (AR) clothing is required It is amisconception that all flame-resistant (FR) clothing (however this is defined) isappropriate for the arc flash hazard; only AR clothing should be worn for protectionagainst the hazard because it has been tested appropriately Flame resistance isdefined by National Fire Protection Association (NFPA) 2113 as “the property of amaterial whereby combustion is prevented, terminated, or inhibited following theapplication of a flaming or non-flaming source of ignition, with or without subse-quent removal of the ignition source” [5] This is inadequate and often misused Theignition source must be considered when using this definition Arc conditions, flashfire conditions, and flashover conditions are all different and could require differentpersonal protective equipment (PPE) for workers exposed to these potential hazards

In 1994, the Occupational Safety and Health Administration’s OSHA 29 CFR1910.269 introduced new legislative language requiring that apparel exposed to arcflash “not increase the extent of injury.” This was when legislation for arc flashprotection first came into play In 1995, NFPA 70E addressed arc flash boundaries;then, in 2000, NFPA 70E introduced the first requirements for clothing levels,known previously as hazard risk categories (currently PPE categories, or PPE lev-els) Today, OSHA requires flame-resistant, arc-rated clothing that matches orexceeds the hazard to protect from the arc flash when the hazard analysis shows

a hazard above 2 cal/cm2 [6] The 2cal/cm2 figure was based on an unpublishedstudy by the utility industry on arc flash effects on pork flesh; NFPA 70E uses1.2cal/cm2based on radiant heat lamp and flame studies from Stoll and Chianta[7] Full-body burn injury models have yet to be used on arc flash due to the smallarea of the body typically hit by the arc flash

Along with OSHA legislation and NFPA 70E standard requirements, the arc- andflame-resistant clothing industry has evolved over the years to improve protection for

workers exposed to the arc flash hazard Doan, Hoagland, and Neal indicated thatworker burn in arc flash events with arc-rated clothing rarely exceeds 25 %of thebody due to the nature of the arc flash hazard [8] In cases of both flame-resistant andarc-rated clothing, the termination, prevention, or inhibition of ignition or flame andprotection values can be attributed to many factors related to the material, includingthe fiber content, fabric construction, chemical reactions (dyes), and moisture.

From 2004–2013, 6,546 people were admitted into U.S burn centers withelectrical burn injuries, and 61 %of these electrical burns occurred under “work-related” circumstances [9,10] According to the fatality reports published by theBureau of Labor Statistics, fatalities with an arc component3decreased 38 %from1992–2014 [11] The decline in fatalities may be attributed to arc testing standardsdevelopment (NFPA 70E), industry participation, and the research and develop-ment of textile technology

FR cotton and aramids have long been the primary line of defense from flameand thermal injuries, and then fiber blends became more frequently used and arenow leading in innovation Today, the market mostly consists of blends, includingthose used for multihazard PPE, with manufacturers making single products withcharacteristics that appeal to the wearer and will also protect from multiple hazards.Different fabrics are available in the marketplace (numerous fiber blends andconstructions, colors, and designs), and each offers both positive and negative traits

to an end user Over time, FR treatments have evolved with scientific advancements

to become more durable When properly applied, they can last for the life of thegarment In fact, some manufacturers guarantee flame resistance for the life of thegarment with proper care in both home and high-temperature industrial launder-ing When human safety is at risk, research and development is constantly evolving

to improve products and to convince people to wear flame-resistant and arc-ratedclothing Most arc flash incidents, without clothing ignition, result in less than 25 %body burn [8], which means a probability of survival between 60 %and 100 %,depending on the age of the victim [12] Prevention of clothing ignition is impera-tive for minimizing injury, providing protection, and increasing survivability in anarc-related incident This information has caused a shift in the industry to switchfrom “noncontributory” clothing to clothing that has been tested for arc and flameresistance So, how do current fabrics work to protect in an arc flash?

Carbonization

Most fibers carbonize when exposed to intense heat, which is an exothermic tion and contributes to injury But carbonized fibers (PanOx, TecGen, and others)can be used to add protection When used in an outer shell, some carbonization can

reac-3 Fatalities with an arc component were defined by ArcWear as fatalities categorized by the Bureau of Labor Statistics from 1992–2010 as “Contact with Electrical Current” with the exception of lightning, and from 2010–2014 as “Exposure to Electricity.”