Indoor Air Quality doc

Historic Overview...3 Evolution of Indoor Air Quality Investigations ...3 Litigation ...5 Differences in Health Effects ...6 A Misguided Premise ...7 Regulations, Requirements, and Guide

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Preface xv

Acknowledgments xvii

About the Author xix

Section I The Starting Line 1 Historic Overview 3

Evolution of Indoor Air Quality Investigations 3

Litigation 5

Differences in Health Effects 6

A Misguided Premise 7

Regulations, Requirements, and Guidelines 7

U.S Government Directives 8

EPA National Ambient Air Quality Standards 8

OSHA Workplace Standards 9

ACGIH Workplace Guidelines 10

ASHRAE Criteria for General Public 10

ACGIH Guidelines Revisited in Older ASHRAE Standard 11

International Enforcement and/or Guidelines 12

ASHRAE Criteria for Residences 12

ASHRAE Criteria for High Performance Buildings 12

Summary 13

References 13

2 Investigation Plan 15

Documents Review 17

Building a Walk-Through 18

Occupied Areas 18

Air Handling System 19

Bathroom Air Exhaust 20

Sewer System 21

Occupant Activities 21

Interviews with Facilities Personnel 21

Maintenance Staff 21

Custodial Staff 22

Observation of Surrounding Areas 23

Assessing Occupant Complaints 23

Questionnaires 24

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Types of Questionnaires 24

Questionnaire Response Rate 24

Informational Data 25

Interviews 27

Summary 27

References 27

3 The Hypothesis 29

Information Review 30

Building Assessment 30

Complaint Occupant 31

Hypothesis Development 34

The Proactive Approach 36

Beyond the Scope 37

Medical Physicians 37

Industrial Hygienists and Toxicologists 38

Psychiatrists 38

Summary 39

References 39

Section II Omnipresent Bioaerosols 4 Pollen and Spore Allergens 43

Occurrence of Pollen and Spore Allergens 43

General Information 44

Spore-Producing Fungi and Bacteria 49

Fungi 49

Molds 49

Mushrooms 52

Rusts and Smuts 53

Slime Molds 54

Bacteria 55

Indoor Source Information 55

Sampling Strategy 56

Sampling and Analytical Methodologies 57

Slit-to-Cover-Slip Sample Cassettes 57

Slit-to-Slide Samplers 58

Analytical Methods 59

Commercial Laboratories 59

Helpful Hints 59

Interpretation of Results 60

Summary 66

References 66

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5 Viable Microbial Allergens 67

Occurrence of Allergenic Microbes 67

Fungi 68

Molds 68

Yeasts 72

Bacteria 72

Bacillus 73

Thermophilic Actinomycetes 74

Air Sampling Methodologies 74

When and Where to Sample 75

Equipment 76

Sample Duration 78

Sample Numbers 78

Culture Media 79

Procedural Summary 83

Diagnostic Sampling Methodologies 83

Where to Sample 84

What to Sample 85

Sampling Supplies 85

Procedural Summary 86

Genus Variability 87

Airborne Exposure Levels 89

Bulk and Surface Sample Results 89

Helpful Hints 90

Summary 90

References 91

6 Pathogenic Microbes 93

Airborne Pathogenic Fungi 94

Disease and Occurrence 94

Aspergillus 94

Histoplasma capsulatum 96

Coccidioides immitis 97

Cryptococcus neoformans 99

Other Pathogenic Fungi 99

Airborne Pathogenic Bacteria 103

Pathogenic Legionella 104

Sampling and Analytical Methodologies for Legionella 105

Helpful Hints 107

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Other Pathogenic Bacteria 108

Disease and Occurrence of Prominent Airborne Pathogenic Bacteria 108

Pathogenic Protozoa 113

Sampling and Analytical Methodology 113

Viruses 114

Summary 115

References 115

7 Toxigenic Microbes 119

Mycotoxins 119

Disease and Occurrence 121

Fungi Identification 123

Toxin Identification 124

Bacterial Endotoxins 127

Sampling and Analytical Methodology 128

Summary 131

References 131

Section III Chemical Unknowns and Gases 8 Volatile Organic Compounds 135

Health Effects and Occurrences 136

Air Sampling Strategy 139

When to Sample 139

Where to Sample 140

How to Sample 141

Rationale for Total VOC Screening (As Opposed to Component Identification) 141

Air Sampling and Analytical Methodologies 143

Solid Sorbents and Air Sampling Pumps 145

NIOSH Method 1500 145

EPA Method TO-17 147

Passive Organic Vapor Monitors 149

Evacuated Ambient Air Containers 151

Whole Air Canisters 152

Ambient Air Sampling Bags 154

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Analytical Comparisons 156

Helpful Hints 158

Summary 161

References 161

9 Mold Volatile Organic Compounds and Mold Detection 163

Health Effects and Occurrences 163

Sampling for MVOCs 166

Sampling Methodology 167

Screening Methodologies 168

Visual Observations 168

Odor Tracking 170

Moisture Testing 171

Summary 174

References 174

10 Carbon Dioxide 177

Occurrence of Carbon Dioxide 178

Sampling Methodologies 180

Direct Reading Instrumentation 180

Colorimetric Detectors 180

Helpful Hints 182

Summary 184

11 Carbon Monoxide 185

Occurrence of Carbon Monoxide 185

Direct Reading Instrumentation 188

Colorimetric Detectors 188

Helpful Hints 190

Summary 191

Reference 191

12 Formaldehyde 193

Occurrence of Formaldehyde 194

Analytical Methodologies 201

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Helpful Hints 202

Summary 203

References 203

13 Product Emissions 205

Global Response and Product Labelling 206

Product Emissions Awareness 208

Sensory Irritation Testing in Environmental Chambers 211

Product Collection 212

Environmental Chamber and Analytical Methodology 216

Measurements of Product Emission Factors 219

Summary 223

References 225

Section IV Identification of Dusts 14 Forensics of Dust 229

Occurrences of Forensic Dust 230

Settled Surface Dust Sampling 234

Specialty Tape 234

Clear Tape 235

Post-it Paper 235

Micro-vacuuming 235

Airborne Dust Sampling 236

Spore Trap 236

Membrane Filters 237

Cascade Impactors 238

Other Methods 238

Bulk Sampling 239

Textile/Carpet Sampling 239

Visible Light Microscopy 240

Specialized Microscopic Techniques 241

X-Ray Diffraction 241

Scanning Electron Microscope 242

Transmission Electron Microscope 243

Electron Microprobe Analyzer 244

Ion Microprobe Analyzer 244

Commercial Laboratories 245

Summary 245

References 246

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15 Animal Allergenic Dust 247

Animal Allergens 248

Mites/Spiders 248

Booklice 251

Cockroaches and Other Insects 251

Domestic Animals 254

Cats 255

Dogs 255

Rodents 256

Farm Animals 257

Other Animals 257

Occurrence of Animal Allergens 257

Screening for Rodents 260

Human Testing 263

Allergenic Dust Testing 264

Other Types of Allergenic Substances 268

Summary 269

References 270

Section V Building Systems and Materials 16 HVAC Systems 275

The Basic Design 275

HVAC Visual Inspection 278

Outdoor Air Intake 278

Outdoor Air in the Vicinity of Air Intake 279

Indoor HVAC Equipment Rooms 279

Filters 279

Condensate Drain Pan 282

Fan Housing 284

Unit and Duct Liner 284

Supply Registers and Return Air Grills 286

Level of Maintenance 288

Air Duct 289

Strategy and Sampling 290

Analyzing the Unknown 292

Interpretation Not So Simple 292

Summary 293

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17 Sewage Systems and Sewer Gases 295

Occurrence of Sewer Gases 296

Hazardous Gases 296

Biological Components 297

Noxious Odor Confusion 297

Investigation Procedures 298

Air Sampling 299

Identification of Components 299

Tracking Sewer Gases 299

Sewage System Inspection Awareness 300

Poorly Installed Sewer Vents 300

Plumbing Fixtures and Associated Traps 301

In-Foundation Line Breaks 301

Septic/Sewage Drains and Lines 302

Summary 303

18 Tainted Chinese Drywall 305

Health Effects 306

Screening Considerations 308

Homeowner Assessment 308

Inspection Screening 308

Components of Chinese Drywall 309

Bulk Sample Collection and Analysis for Identification of Chinese Drywall 311

Sample Collection 311

Sample Analysis 312

Suspect Air and Headspace Sampling for Off-Gassing Components 313

Sample Analyses 314

Corrosion Testing 315

Microbiological Testing 316

Chinese Manufactured Drywall 317

Off-Gassing Sulfur-Containing Gases 317

Causes Corrosion 318

Summary 318

References 319

19 Green Buildings 321

21st Century Green 322

Green Flush-Out Protocols 323

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LEED Indoor Air Quality Management Plan 324

ANSI/ASHRAE Standard 189.1—Construction and Plans for Operation 324

Summary 334

References 334

Glossary 335

Appendix A: Abbreviations/Acronyms 345

Appendix B: Units of Measurement 347

Appendix C: Allergy Symptoms 349

Appendix D: Classification Volatile Organic Compounds 353

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The intent of this book is to provide environmental professionals, trial hygienists, and indoor air quality specialists with the latest and great-est methods in response to the knee-jerk indoor air quality challenges andfor assessing new construction prior to occupancy The focus is to provide

indus-a “prindus-acticindus-al guide” for developing indus-a theory indus-and following it through to theidentification and interpretation of unknown air contaminants

Section I, “The Starting Line,” provides a historic overview with regulatorylimits and guidelines; preliminary investigation methods including meansfor assessing complaints; and a means for speculation, narrowing the huntfor offenders With a well-defined hypothesis, the investigator must test thehypothesis by sampling Direction is provided for determining what, when,where, and how to sample for the various airborne components that may

be found in indoor air quality situations The components are broken intobioaerosols, chemicals, and dust

Section II, “Omnipresent Bioaerosols,” is inclusive of microbials only Thissection discusses sampling methodologies for microbial allergens such as fungiand pollen; invasive pathogenic microbes; and toxigenic molds/bacteria Otherbiological components such as animal allergens are contained within anothersection

Section III, “Chemical Unknowns and Gases,” contains sampling ogies for volatile organic compounds; microbial volatile organic compounds;carbon dioxide; carbon monoxide; formaldehyde; and product emissions.The microbial volatile organic compounds are discussed within this sectionbecause some researchers speculate that microbial (e.g., mold) by-productsmay contribute to the total volatile organic compounds in an enclosed build-ing Yet some use the techniques to locate mold in wall spaces

methodol-Section IV, “Identification of Dusts,” contains sampling methodologies foranimal allergens such as dust mites and forensic methods for identifyingdust components Dust components can be checked for chemicals adsorbedonto or settled on the surface of dust particles, toxic metals, and varioustypes of fibers (e.g., resin-coated fiberglass)

Section V, “Building Systems and Materials,” is a new section Often looked and underutilized, sewage gases and HVAC systems are discussedand assessment guidelines provided The topic of tainted Chinese drywallhas become a bucket of worms—legally, financially, and analytically In the

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over-chapter “Tainted Chinese Drywall,” the background information and moreprominent sampling methodologies are discussed The last chapter is “GreenBuildings.” The concept of green buildings has shifted from resource con-servation only to resource conservation and healthy indoor air quality TheLeadership in Energy and Environmental Design (LEED) Rating System andAmerican Society of Heating, Refrigerating and Air Conditioning Engineers(ASHRAE) 189.1 are discussed, and air sampling methodologies and samplelimits are detailed.

As a passion for detective work is a delightful motivator for performing anindoor air quality assessment, the person performing such a survey is hereinreferred to as the “investigator.” The investigator’s greatest asset is his or herability to weave through a convoluted web of complex problems This bookprovides strategies and tools to herald Sherlock Holmes!

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I wish to dedicate this book to those who have contributed their time andtechnical expertise to review and update technical information that isconstantly changing A special thanks to Sean Abbott, PhD, mycologistextraordinaire and director of Natural Link Mold Lab, for reviewing theextensive section on bioaerosols Paul Pope, MS, analytical chemist for ALSLaboratory Group, made whole the table on EPA air monitoring method-ologies, reviewed “Green Buildings”, and shared his company’s uniquefindings regarding tainted Chinese drywall He truly has been an invalu-able resource of all information—established and evolving Vince Delessiowith EMSL provided information regarding tainted Chinese drywall aswell, and Marilyn Black, PhD, with Air Quality Services reviewed theevolving chapter on “Product Emissions.” Each of these contributors hasbeen patient, withstanding my endless questions and ceaseless requestsfor data

Last, but certainly not least, my husband has been my rock of sanity inthe final throes of a topic that changes daily As my dog runs in circles, thehouse is in disarray, and the world races on, I offer my gratitude and heartfeltthanks to all!

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Kathleen Hess-Kosa is the president/owner of Omega Southwest nmental Consulting In 1972, she received her bachelor of science degree inmicrobiology with a minor in chemistry from Oklahoma State University.After serving as an officer in the Air Force for three years, she returned toschool and earned a master of science degree (1979) in industrial hygienefrom the College of Engineering at Texas A&M University Her researchinvolved an animal toxicological study and was conducted at the College

Hess-Kosa has since conducted numerous Phase I environmental siteassessments and published a book concerning the topic She has activelypursued obscure sources of information and training to better address thecomplex nature of environmental issues, indoor air quality, and multiplechemical sensitivity She has successfully identified sources of indoor airquality problems in more than 90 percent of the numerous investigationsperformed, and she has been instrumental in rectifying 100 percent of thescenarios It took some time to get to this point, but some of the informationthat was collected and has been used by Hess-Kosa is presented within thisbook

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The Starting Line

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Historic Overview

An estimated 1.34 million office buildings have problems with air ity, and approximately 30 percent of all office employees are potentiallyexposed to the health effects of poor indoor air quality.1More than 50 millionAmericans suffer from asthma, allergies, and hay fever Chronic bronchitisand emphysema increased by more than 85 percent between 1970 and 1987.Close to 100,000 Americans die each year because of complications due tochronic obstructive pulmonary diseases (COPD).1More than 50 percent ofour nation’s schools have poor ventilation and significant sources of pollu-tion in buildings, where an estimated 55 million students and school staffmembers are affected by poor air quality Health effects are predominantlyobserved in children with asthma In the last 15 years, a 60 percent increase

qual-in the qual-incidence of asthma has occurred amongst school-aged children.Today approximately 8 percent of all school-aged children have been diag-nosed with asthma

In an effort to address many of the prevailing and ever-looming issues,indoor air quality investigative methodologies are evolving Indoor air qual-ity is complex!

Many indoor air quality situations culminate with litigation, differences inhealth impact, differences in perceived health effects, regulatory limits, andguidelines Guidelines are being created by recognized public agencies, andinvestigators are being called upon to make decisions with minimal supportand direction Finally, indoor air quality investigations are becoming moreproactive, part and parcel of the new “healthy” green buildings

Evolution of Indoor Air Quality Investigations

The Environmental Protection Agency (EPA) ranks indoor air pollutionamong the top four environmental risks in America People spend about

90 percent of their lives indoors, and pollution is consistently two to fivetimes higher indoors than outdoors The indoor pollutant levels have beenreported as high as 100 times the levels encountered outside

Since the worldwide energy crisis in 1973, advances in energy efficiencybuilding construction have not been without a downside In an effort toconserve fuel in commercial and residential buildings, builders started

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constructing airtight buildings, inoperable airtight windows, and reducedair exchange rates.

In well-weatherized homes, the air exchange rate is 0.2 to 0.3 air changesper hour In older, less energy efficient homes, exchange rates are as high as

2 changes per hour In energy efficient office buildings, air exchange ratesare around 0.29 to 1.73 changes per hour The higher exchange rates in olderbuildings dilute and clean indoor air contaminants, whereas the newerbuildings retain them Thus, illness associated with new buildings has come

to be referred to as “tight building syndrome.”

By 1986 the news media began to sensationalize the condition and coinedthe term “sick building syndrome.” Sick building syndrome is a conditionwhereby the occupants of a building experience health and comfort prob-lems that seem to be linked to a building, and the cause is unknown Indoorair quality investigative methods to identify unknown sources of building-related health complaints have continued to evolve

At the low end of the evolutionary scale, formaldehyde off-gassing fromfurnishings in office buildings and from particleboard in mobile homes wastargeted as the single most investigated culprit One article, published in 1987,refers to formaldehyde as a “deadly sin.” New media touted, “It Could BeYour Office That Is Sick,” “Tight Homes, Bad Air,” and “The Enemy Within.”Sensational! Insurance claims were on the rise, and insurance companies began

to exclude “claims arising directly or indirectly out of formaldehyde whether ornot the formaldehyde is airborne as a fiber or particle, contained in a product,carried or transmitted on clothing contained in or a part of any building, build-ing material, insulation product or any component part of any building.”With the passage of time it became clear that the problem was not a sim-ple one, and looking for unknowns was not a simple process As industrialhygienists scrambled to identify other possibilities, office building investi-gations became research projects The cost was in the thousands of dollars.Ongoing complaints recurred, and ultimately the industrial hygiene profes-sion pioneered the investigative and sampling methodologies that are inplay today

The original hit list evolved to include not only formaldehyde but bon monoxide, carbon dioxide (fresh air/indicator gas), and total organics.Industrial hygienists further attempted to identify volatile organic com-pounds (VOC) Many began looking at carpet emissions (e.g., 4-phenylcy-clohexene), tobacco smoke, and airborne/surface allergens All things werepossible All possibilities were “open for discussion.”

car-In the latter part of the 20th century, residential concerns were beingaddressed with greater frequency Considerations for sampling includedformaldehyde, carbon monoxide, carbon dioxide, allergens, electromagneticradiation, radon, and a medley of household products (e.g., VOC)

By 2000, mold became the new “hot topic.” The focus shifted from dehyde and other chemicals to mold Media headlines heralded, “The Dish

formal-on Hotel Air,” “Moldy Attitudes formal-on Indoor Air Need a Good Scrubbing,”

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“The Good, The Bad and The Moldy,” and “Fungal Sleuths.” The shift wasphenomenal In the public’s eye, mold had become the single most cause ofindoor air quality complaints This was a little shortsighted, yet it was theperceived reality Requests to perform indoor air quality studies were equiv-alent to a “mold study” even when it wasn’t visibly apparent Many in thepublic had turned a blind eye to other possibilities.

In many cases, when the elusive mold blame game failed and complaintspersisted, investigators were forced to revert back to the basics and carpetemissions Yet even today very few investigators go the extra mile of spend-ing the extra money to identify VOC components and to consider other pos-sibilities (e.g., forensic dust and fine particles) Other considerations becameemissions from copy machines, sewer gases, ozone, and outdoor air The lat-est concern has been tainted Chinese drywall

In the 21st century, “green buildings” have become the focus Althoughenergy and resource conservation were the primary concern, healthybuildings began to take on a whole new complexion Green buildings arebecoming synonymous with healthy buildings Product emissions testingand green certification of products has raced to the forefront, beginning

to parallel green building concerns, and indoor air quality standards forhigh-performance (e.g., office) buildings have been proposed as of 2009.The wave of the future is for buildings to be assessed as a unit Buildingsystems and materials are seen as a total package The swath of complexities

is great Indoor air quality challenges are many, and guidelines are beingdeveloped The future is now!

Litigation

Managing indoor air quality has become one of the more demanding lenges facing school administrators and potentially office facility managers.Legal action, negotiation, and arbitration have redefined what is considered

chal-as acceptable An acceptable response to indoor air quality complaints thushas come to be defined in terms of reasonable standard of care

If a student or faculty member initiates an indoor air quality claim against

a school, the person must establish certain facts First, the claim must onstrate that the school has a duty to protect faculty from reasonably fore-seeable harm Second, after having demonstrated the existence of a duty, theclaimant must demonstrate that the school failed to provide a reasonablestandard of care This constitutes negligence For example, if a staff mem-ber reports building-related health symptoms, and the administrators fail toshow a reasonable standard of care, ignoring the complaint would constitute

dem-a cledem-ar fdem-ailure to show redem-asondem-able cdem-are Third, the bredem-ach must be directlyrelated to the harm claimed Recently the term sick building syndrome has

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come to mean that a building is causing health problems, and the source isunknown.2

In the court case of Dean H.M Chenensky et al v Glenwood Management

Corp et al., there is a pending lawsuit involving $180 million regarding mold

exposures In another case, Robert E Coiro et al v Dormitory Authority of the

State of New York, the plaintiffs are seeking $65 million Other suits involvingvarious indoor air quality allegations are ongoing

Thus, the driving force in indoor air quality investigations has become fear

of litigation The cost of a thorough indoor air quality investigation is small

as compared to the cost of litigation

Differences in Health Effects

The health effects of poor indoor air quality are dependent upon several tors Relevant considerations when determining potential health effects on apopulation are the effect of each air contaminant, concentration, duration ofexposure, and individual sensitivity

fac-The air contaminant may be an allergen, or it may be a carcinogenic chemical.The allergen will cause an immediate reaction with minimal long-term effects

A carcinogenic chemical may not have any warning signs of exposure but maycause cancer years after exposure It may be an irritant with passing healtheffects, or it may be a sensitizing chemical (e.g., isocyanates) whereby futureexposures may result in an extreme immune response Indoor air generallyconsists of a complex medley of substances that may have one or a combination

of effects, and those substances that have the same health effect may not gularly cause health problems, whereas two different substances (e.g., irritants)may significantly impact human health when present at the same time.Proper diagnosis is of course dependent upon proper identification of allcontributing components Then, once the contaminants have been identified,concentration should be ascertained

sin-Although there are known concentrations for many air contaminants atwhich well-defined health effects become evident, exposure levels definingthe more subtle health effects are not as well-researched Furthermore, of theestimated 100,000 toxic substances to which building occupants are poten-tially exposed, fewer than 400 recommended exposure limits exist for indus-trial chemicals The Occupational Safety and Health Administration (OSHA)regulates industry and EPA regulates outdoor ambient air quality Currently,

no regulatory agencies control indoor air quality exposure limits

Exposure duration is of particular concern in assessing indoor air qualityexposures In office buildings, exposures are generally 8 to 10 hours a day,five days a week In residential structures, exposures may be up to 24 hours

a day, seven days a week As some substances build up in the body over

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time, 24-hour exposures may result in an accumulation with the subsequentimpact on health effects Thus, the impact of a given concentration of aircontaminant is less in office buildings than in residences Other areas thatshould be considered potential long duration exposures include hospitalpatient rooms, hotels, mental wards, and prison cells.

Individual sensitivity contributes a huge variable to the combination offactors affecting the health of building occupants Infants, elderly people,and sickly people are the most vulnerable to the health effects of air contami-nants Immune-suppressed individuals (e.g., AIDS patients and organ trans-plant recipients) and those with genetic diseases (e.g., lupus erythematosus)are particularly sensitive to common molds Individuals who drink alcohol

in excess are more susceptible to air contaminants that may affect the liver.People with dry skin are more susceptible to further drying and skin pen-etration by chemicals Those who smoke tobacco products have diminishedbody defense mechanisms Certain medications enhance the effect of envi-ronmental exposures Individuals with predisposed conditions (e.g., lungsdamaged by fire) may have a heightened response to air contaminants

A Misguided Premise

As they compare the indoor to industrial environments, traditional trial hygienists see the good, the bad, and the ugly The indoor air qualityenvironment is the good, and industrial environments are the bad and ugly.This is a misguided premise that requires comment

indus-Indoor air quality exposures involve multiple exposures to unknown stances in enclosed environments often with minimal fresh air, no exposureduration limits, and a wide range of individual susceptibility Industrialexposures involve limited exposures to known chemicals in work environ-ments with local exhaust ventilation, limited exposure duration, and healthyadults The indoor environment does not begin to compare to the dirt andgrime of industry Yet clearly there are differences

sub-A tight building has multiple factors that can result in sick building drome An enclosed environment does not mean clean air

syn-Regulations, Requirements, and Guidelines

Currently, federal regulatory limits for indoor air quality are limited U.S.government directives are limited in scope The EPA Ambient Air QualityStandards are limited to outdoor environmental pollution, and OSHA

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mandates are limited to industrial pollution Yet these regulated limits havebeen found inadequate or marginal at best in responding to cases involvingindoor air quality.

In an effort to stem the tide of indoor air quality health complaints, variousrecognized public contributors have recommended guidelines Regulatorystandards are mandated and guidelines are recommended The recom-mended guidelines are more apt to appropriately address indoor air qualityproblems than are regulatory standards

Guidelines are developed, reviewed, and updated by professional expertsand are frequently cited Formal guidelines of national importance are theAmerican Conference of Governmental Industrial Hygienists (ACGIH)and the American Society of Heating, Refrigerating and Air ConditioningEngineers (ASHRAE), and there are some international contributors

U.S Government Directives

A limited number of federal agencies have been given directives to considerindoor air quality in their standards In 1994, the Department of Energy wasdirected to consider the impact of energy efficient options on habitability andpeople, and to achieve a balance between a healthy environment and energyconservation.3In 1997, the Department of Housing and Urban Developmentpromulgated standards for the construction and safety of manufacturedhousing that includes features related to indoor air quality.4

EPA National Ambient Air Quality Standards

The EPA air quality focus is to protect human health outdoors in the ent air The principal program that may be of some value to the reader isthe National Ambient Air Quality Standard The intent of this standard is

ambi-to control emissions of six pollutants and their precursors when released inlarge quantities (e.g., vehicle exhausts and industrial emissions) This stan-dard may be applied in indoor air quality investigations where the outsideair may potentially contribute to exposure levels indoors, such as in largenonattainment cities Nonattainment means the city does not comply withone or a combination of the air quality standards as set forth in Table 1.1.Where exceeded outdoors, the National Ambient Air Quality Standards arelikely to be exceeded indoors as well

Nonattainment areas are generally around large cities (e.g., Los Angelesand New York City) and industrial areas (e.g., New Jersey), but nonattainmentsites are sometimes encountered in unpredictable, isolated areas They aredesignated by state and county, and the regional EPA office can provide thelatest information upon request

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OSHA Workplace Standards

OSHA claims jurisdiction over all workplace environments The place includes indoor air quality exposures in office buildings as well as inindustry and construction Yet when it comes to indoor air quality, OSHAcapabilities are limited in that the contaminants must be known and per-missible exposure limits are based on outdated limits published by ACGIH

work-in 1968

TABLE 1.1

National Ambient Air Quality Standards (NAAQS)

Nitrogen dioxide 0.053 ppm (100 µg/m 3 ) Annual (arithmetic

(Applies only in

a Not to be exceeded more than once per year.

b Due to lack of evidence linking health problems to long-term exposure to coarse particle pollution, the agency revoked the annual PM10 standard in 2006 (effective December 17, 2006).

c Not to be exceeded more than once per year on average over three years.

d To attain this standard, the three-year average of the weighted annual mean PM2.5 tions from single or multiple community-oriented monitors must not exceed 15.0 µg/m 3

concentra-e To attain this standard, the three-year average of the 98th percentile of 24-hour concentrations

at each population-oriented monitor within an area must not exceed 35 µg/m 3 (effective December 17, 2006).

f To attain this standard, the three-year average of the fourth-highest daily maximum 8-hour average ozone concentrations measured at each monitoring station within an area over each year must not exceed 0.08 ppm.

g (a) The standard is attained when the expected number of days per calendar year with mum hourly average concentrations above 0.012 is <1, as determined by Appendix H (b) As

maxi-of June 15, 2005, the EPA revoked the 1-hour ozone standard in all areas except the 14 8-hour ozone nonattainment Early Action Compact (EAC) areas.

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Not only are most OSHA limits easily attained in indoor air quality tigations, but there are no provisions for low-level irritants, molds, and aller-gens Those investigators who do insist on applying the OSHA standards inoffice environments will generally find a dead-end street These same inves-tigators often state that the OSHA standards have been met so there must not

inves-be a problem In a building where 80 percent of the occupants have healthcomplaints, a statement that infers the only problem is mass hysteria willmost assuredly find the investigator’s credibility questioned The originalOSHA exposure limits were derived from the 1968 ACGIH recommenda-tions Limits for only a handful of chemical contaminants (e.g., asbestos andbenzene) have since been updated For this reason, most industrial hygien-ists consider OSHA limits outdated and opt to use the ACGIH guidelines.Although backed up by the force of federal law, the OSHA limits are rarelyexceeded in office environments where one or more of the contaminantshave been properly identified The complex nature of indoor air quality isnot supported by OSHA limits

ACGIH Workplace Guidelines

The American Conference of Governmental Industrial Hygienists (ACGIH)

is a professional society of scientists that annually reviews and recommendsguidelines to industrial hygienists for use in the assessment of occupationalworkplace exposures

The American Conference of Governmental Industrial Hygienists (ACGIH) limits are intended for use in the practice of industrial hygiene

as guidelines or recommendations in the control of potential workplace health hazards and for no other use … These limits are not fine lines between safe and dangerous concentrations nor are they a relative index

of toxicity … A small percentage of workers may experience discomfort from some substances at concentrations at or below the threshold limit, and a smaller percentage may be affected more seriously by aggrava- tion of a pre-existing condition or by development of an occupational illness.

There are around 400 chemicals listed with recommended 15 minute and8-hour exposure limits These guidelines were created to address exposures

in the workplace Occupational exposures are generally limited to 8-hourexposure durations for healthy adults between the ages of 18 and 65 Thus,the ACGIH exposure guidelines do not apply to residential exposures wherethe exposure parameters differ ASHRAE has addressed this consideration

ASHRAE Criteria for General Public 5

In 1981, The American Society of Heating, Refrigeration and Air Conditioning(ASHRAE) introduced a revised mechanical ventilation standard that is now

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referred to as the “Ventilation for Acceptable Indoor Air Quality Standard.”ASHRAE developed and evolved consensus guidelines to address indoor airquality in public buildings.

Consensus is defined as “substantial agreement reached by directly andmaterially affected interest categories This signifies the concurrence of morethan a simple majority, but not necessarily unanimity Consensus requiresthat all views and objections be considered, and that an effort be madetoward their resolution Compliance with this is voluntary until and unless

a legal jurisdiction makes compliance mandatory through legislation.” Thisdefinition is according to the American National Standards Institute (ANSI),

of which ASHRAE is a member.6

The purpose of the standard is to “specify minimum ventilation ratesand indoor air quality that will be acceptable to human occupants and areintended to avoid adverse health effects.” The health effects information andacceptable exposure limits rely on recognized authorities and their recom-mendations Thus, the ASHRAE standard on “Ventilation for AcceptableIndoor Air Quality” has become the most commonly cited guideline forinvestigating indoor air quality in commercial and institutional facilities inthe world

The standard is intended to provide ventilation design and maintenancepractices for air handling systems except where more stringent designspecifications apply It should also be noted that in 1999, ASHRAE issued

a disclaimer that “acceptable indoor air quality may not be achieved in allbuildings meeting the requirements of this standard.”5The 2007 disclaimerhas been slightly altered to reflect “any tests conducted under its Standards

or Guidelines will be nonhazardous or free from risk.”6

ACGIH Guidelines Revisited in Older ASHRAE Standard

In a 1999 publication, ASHRAE recommended the investigator start with

an acceptable limit of one-tenth of the ACGIH TLVs for acceptable indoorair quality

A concentration of 1/10 TLV would not produce complaints in industrial population(s) in residential, office, school, or other similar environments The 1/10 TLV may not provide an environment satisfac- tory to individuals who are extremely sensitive to an irritant … Where standards or guidelines do not exist, expert help should be sought in evaluating what level of such a chemical or combination of chemicals would be acceptable 7

non-This recommendation has not continued to the succeeding publications,but it has been referred to by the California Relative Exposure Limits (REL)for individual organic compounds The California REL is frequently deferred

to in assessing product emissions

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International Enforcement and/or Guidelines

In ANSI/ASHRAE 62.1-2007, “Ventilation for Acceptable Indoor Air Quality,”outdoor and indoor enforceable regulatory limits and nonenforceable guid-ance limits are listed in Appendix B, Table B-1, of the Standard The Canadianmaximum exposure limits are for residences The Environmental ProtectionAgency (EPA) and World Health Organization (WHO) limits are for indoorand outdoor exposures All others are for outdoors environmental air orindustrial exposures only The Canadian limits tend to be the lowest, moredifficult to attain

ASHRAE Criteria for Residences

ANSI/ASHRAE 62.2-2007, “Ventilation for Acceptable Indoor Air Quality

in Low-Rise Residential Buildings,” is the only ASHRAE standard thataddresses residential indoor air quality, but it does not address acceptableair quality issues as do the ANSI/ASHRAE 62.1 series for office buildings.The standard merely sets guidelines to achieve acceptable indoor air qualityfor homes by ensuring minimum ventilation Its purpose is to address onlymechanical ventilation by means of:

• Source control of moisture and other specific improvements throughthe use of exhaust fans

• Local ventilation in wet rooms to remove odor and moisture

• Carbon monoxide detectors

• Criteria to minimize back-drafting and other combustion-relatedcontaminants

• Provision to reduce contamination from attached garages

• Guidance on how to select, install, and operate systems

As there are no actual recommended ASHRAE standards for residences,the office building standards (ANSI/ASHRAE 62.1-2007 and 189.1) may bereferred to for guidance

ASHRAE Criteria for High Performance Buildings

In 2010, ASHRAE published a “Standard for the Design of High-Performance,Green Buildings—Except Low-Rise Residential Buildings.” In this publica-tion, recommended air quality limits are lower than or equal to all U.S andinternational standards

The intent was to pave the way for more energy efficiency/resource servation and to provide for healthy building construction that requiresindoor air quality testing Whereas the 1998 Leadership in Energy andEnvironmental Design (LEED) rating proposes an option to perform indoor

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con-air quality testing, ASHRAE 189.1 mandates con-air testing after construction,prior to occupancy of high-performance (e.g., office) green buildings Formore information and details, see Chapter 19, “Green Buildings.”

Summary

Tight building syndrome and sick building syndrome have become hold phrases As indoor air quality complaints escalate, ignored healthcomplaints in public buildings are becoming the rationale for lawsuits andhomeowners are living in fear In an effort to stem the tide, environmentalprofessionals are developing guidelines and recommendations that specifi-cally address indoor air quality

house-Indoor air quality investigations have yet to be standardized, regulated,

or managed with consistency Thus, those performing these investigationsmust develop a strong knowledge base and actively pursue each new casewith the enquiring mind of a detective

4 42 U.S.C section 6851 (1997).

5 ASHRAE Standards Committee Ventilation for Acceptable Indoor Air Quality.

ASHRAE Publications, Atlanta, Georgia ASHRAE 62 (1999).

6 ASHRAE Standards Committee Ventilation for Acceptable Indoor Air Quality.

ASHRAE Publications, Atlanta, Georgia ASHRAE 62 (2007).

7 ASHRAE Standards Committee Ventilation for Acceptable Indoor Air Quality:

ASHRAE Publications, Atlanta, Georgia ASHRAE 62, Appendix C (1999), p 17.

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Investigation Plan

In 1984, the World Health Organization (WHO) suggested that up to 30 cent of all new and remodeled buildings worldwide experienced excessiveindoor air quality complaints.1From 1989 to 1990, The National Institutefor Occupational Safety and Health (NIOSH) indoor air quality requestsjumped from 8 percent to 52 percent In 1989, NIOSH completed approxi-mately 500 indoor air quality investigations and concluded that 34 percent

per-of all sick building syndrome buildings were associated with indoor aircontaminants, outdoor air contaminants, building materials, or microbes.Fifty-two percent of the buildings had inadequate ventilation, and 13 per-cent were “source unknown.”2See Figure 2.1 It is not clear whether the

13 percent was due to an inability to identify unknown sources or due totypical office building complaints encountered in all office buildings.Although many environmental professionals have found a typical com-plaint rate in office buildings to be 8 percent to 12 percent, one publicationclaims a normal dissatisfaction rate of 20 percent.3Yet there is no fine linebetween typical and abnormal

The most typical complaints encountered in all buildings are that of perature (too hot or too cold) and humidity extremes (too dry) Less com-mon complaints are that of odors (e.g., cafeteria food in an executive’s office),unwanted noise (e.g., copy machine operation), and inadequate lighting Inother instances, complaints may be linked to job-related and occasionallypersonal psychosocial stress (e.g., headaches) and poor ergonomic condi-tions In a survey funded by the Environmental Protection Agency (EPA),

tem-20 nonproblem buildings around the United States were surveyed in order

to develop a baseline of complaints in structures not identified as sick ings Data regarding specific complaints arising from buildings with “noindoor air quality problems,” falling within the 20 percent normal dissatis-faction rate, was as follows:

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Sick building syndrome symptoms are very similar to buildings nated noncomplaint, nonproblem buildings The difference is simply in thenumber (or percentage) of complaints.

desig-The greater “normal” is exceeded, the greater building-related sick ing syndrome becomes a facility management concern Clearly, when thecomplaint rate in a 20-story office building exceeds 80 percent, there is aproblem But what about complaints from 20 percent of the entire buildingwith 100 percent of the 15 occupants located within an isolated area of thehigh rise complaining? What about a small office of 20 occupants with fivecomplaining?

build-Don’t rule out sudden events! Where symptoms occur immediately,there has likely been an event or sudden release of a toxic substance into

an enclosed area The release, occasionally referred to as the smoking gun,may or may not involve an entire building For example, a prankster releasedmace into the air in a grocery store Eye irritation and breathing difficul-ties with a sense of suffocation resulted in an evacuation of the entire store.This scenario led to a series of events that culminated with carbon monoxideexposures from the emergency response fire truck exhaust in front of thestore where the patrons and store employees gathered outside

Poor indoor air quality and poor facility management response is a mula for disaster Poor air quality spells poor employee moral, increasedsick days, and litigation Many facility managers are becoming ever moreaware and wary of the need for good indoor air quality In an Internetpublication:

for-According to a ground breaking Swedish study appearing in The International Archives of Occupational and Environmental Health, 45%

of “so-called” sick building syndrome victims — treated in hospital clinics — no longer have the capacity to work Twenty percent of the suf- ferers are receiving disability pensions, 25% are “on the sick-list.” 4

Although the truth behind the statement remains to be seen, media ated hysteria makes the article a reality The cost of poor perceived or actualindoor air quality by far outweighs the cost of a good, sound indoor air qual-ity assessment!

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An effective indoor air quality assessment involves a series of steps thatare outlined herein Each step is a tool, and a tool is only as good as theuser With knowledge and experience, some tools may not be necessary Theinvestigator may choose to overlook some steps in one situation and followthem in their entirety in another For example, an investigation initiated bycomplaints of headache and gasoline odors may require a couple of inter-views and a building walk-through in order to locate possible sources ofgasoline No two investigations are the same!

Documents Review

Obtain and review the building layout, mechanical blueprints (if available),

an inventory of activities, and an inventory of known chemicals, custodialactivities, and pesticide treatment activities Additionally, some investigatorsattempt to obtain full architectural plans, specifications, submittals, sheetmetal drawings, commissioning reports, adjusting and balancing reports,inspection records, and operating manuals

The building layout is a must have, particularly in public buildings It may

be in blueprint form, or the schematic may be a fire exit plan The latter is morelikely to be available and updated As-built drawings are rarely kept up to date.Mechanical blueprints for a building are rarely available, especially forolder buildings If they are present, however, they are often outdated Thisdocument is one of the single most important documents the investigatorwill require An alternative backup is to have someone knowledgeable inthe mechanical operation of the building (e.g., building engineer or main-tenance) sketch which air handler supplies what areas This same personshould also be asked to update altered as-built drawings to the best of his orher ability

Identify each area by activity/activities Get specific information Forinstance, activities may include word processing and filing carbonless copypaper, legal casework, operating a blueprint copy machine, and gluing/paste-up work The facilities personnel may or may not be able to providethis information If not available, the activity information can be collectedduring the actual walk-through

An inventory of chemicals should be collected wherein the potentialfor chemical exposures exists In most public and institutional buildings,chemical information is sketchy at best Management may either generalizesubstances as custodial cleaning fluid or copy toner, or they may be able toprovide material safety data sheets for all chemicals housed on the premises.The latter is the least likely to occur

Relevant to the investigator during the walk-through and while ing an air sampling strategy, custodial activities and schedules should be

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develop-obtained along with the type of supplies used This may take some research

on the behalf of the facilities manager or may require the investigator toschedule interviews with the custodial personnel

Custodial activities are an often overlooked contribution to indoor airquality because custodial personnel generally operate after hours Yet theiractivities have been found to impact the indoor air quality significantly Inone case, the custodial personnel used feather dusters in the office spacesand emptied their vacuum waste while in the office spaces (and wearing apaper respirator) In the morning, the office employees complained of visibledust in the light streaming through the windows

Pesticide treatment activities are generally out of sight and out of mind.Although the scheduled peak treatment periods may coincide with com-plaints, the health effects of pesticides may be overlooked In one case,spraying for a cockroach infestation resulted in airborne allergenic parts andpieces, a situation that could well have been avoided with roach motels

Building a Walk-Through

The intent of the walk-through is to acquire an overview of the building andoccupant activities A residential walk-through is considerably less compli-cated than one involving public buildings

In public buildings, an initial walk-through should be planned and nated Schedule the walk-through to include the occupancy periods and nor-mal building operation This accomplishes two things It shows response toand concern for the occupant complaints, and the building can be assessed

coordi-as it is when fully operational The investigator is less likely to overlook evant considerations during peak complaint periods

rel-In the interest of time, some investigators scale down the initial through considerably on the first visit by performing a documents reviewand assessing questionnaires With this information, the investigator canthen develop an air sampling strategy and complete the walk-through at alater date while collecting air samples Each investigator should be flexibleenough to revise the approach, as scenarios and conditions differ from oneinvestigative building to the next

walk-Occupied Areas

The investigator should have a set of floor plans (or a schematic) with all evant information assessed during the documentation review Several colormarkers may be helpful along with a pen, paper, clipboard (or binder), andflashlight A building representative familiar with the air handling system

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rel-should accompany the investigator with a set of keys and tools, and a laddershould be accessible as well.

The general condition of the occupied spaces in a building should beassessed Some items to look for include, but are not limited to, the following:

• Odors

• Lint or soiling on carpets

• Dirt on sheet vinyl and floor tiles

• Dust on surfaces (e.g., desks and ledges)

• Water damage stains (e.g., ceiling tiles with tealike stains)

• Suspended dust in air (e.g., observed in light)

• Moisture collecting on surfaces (e.g., condensation on windows)

• Dirt and debris around the air diffusers

• Cloth versus vinyl upholstery

• Presence of homeowner air purifiers

• Cleanliness of kitchen/food areas

• Rotting food in office spaces and trash receptacles

• Presence of plants

• Wall penetrations

• Peeling paint and vinyl wallpaper

• Storage of chemicals

Continue to add to the list as the situation dictates Always keep in mind, “If

it looks out of place, it probably is!” Ignoring this old adage could culminate

in an oversight Even if an unexplained sense of something not right shouldoccur, attempt to identify the reason

Air Handling System

An investigation of the air handling system generally requires some basicknowledge beyond the scope of this book Such an assessment may requirethe assistance of a mechanical engineer or an industrial hygienist knowl-edgeable in HVAC systems

Although the investigator may not be knowledgeable, air handling tems are one of the single most important contributors or solutions to indoorair quality problems Some of the more basic items to look for in a centralizedair handling unit include:

sys-• Rust, damage, and water leaks around the exterior of the units

• Condition and amount of water in the drip pans

Tiêu đề	Indoor Air Quality The Latest Sampling and Analytical Methods
Trường học	Taylor & Francis Group
Chuyên ngành	Indoor Air Quality
Thể loại	Sách
Năm xuất bản	2011
Thành phố	Boca Raton

Định dạng
Số trang	378
Dung lượng	6,22 MB