EN 1366-2, Fire resistance tests for service installations — Part 2: Fire dampers EN 1507, Ventilation for buildings — Sheet metal air ducts with rectangular section — Requirements for
General
Refrigerating equipment may be sited outside the building in the open air or in a machinery room or in occupied areas or in unoccupied areas not designated as a machinery room
NOTE The refrigerating equipment can be contained in a ventilated enclosure provided by the manufacturer Requirements for this enclosure are given in EN 378–2:2016, 6.2.15.
Refrigerating equipment located in the open air
Refrigerating systems installed outdoors must be strategically located to prevent leaked refrigerant from entering buildings and posing risks to people and property It is essential that refrigerant cannot flow into any ventilation openings, doorways, trap doors, or similar access points in the event of a leak Additionally, if a shelter is used for outdoor refrigerating equipment, it must include natural or forced ventilation to ensure safety.
A room is classified as being in the open air if at least one of its longer walls features louvres that provide 75% free area and cover a minimum of 80% of the wall area, or if multiple walls meet equivalent criteria for outdoor exposure.
Refrigeration systems located outdoors in areas where refrigerant release may accumulate, such as below ground, must adhere to gas detection and ventilation standards for machinery rooms as outlined in clauses 8 and 9 of section 5.13 Additionally, for refrigerants classified as 2L, 2, and 3, the ignition source requirements specified in EN 378-2:2016, section 6.2.14, are applicable when relevant.
Refrigerating equipment located in a machinery room
When a machinery room is chosen for the location of the refrigerating equipment it shall meet the requirements specified in 5.1 to 5.14
A risk analysis of the refrigerating system, considering the manufacturer's safety concept, refrigerant charge, and safety classification, must be performed to assess the need for a dedicated refrigeration machinery room.
NOTE 1 National regulations may set specific requirements for the use of separate refrigeration machinery rooms
For underground systems utilizing class 3 flammable refrigerants with a charge exceeding 'm2', it is essential to install an additional gas detector along with an audible and visual alarm, ensuring compliance with the specified detector standards.
NOTE 2 Additional requirements may be needed for refrigerating systems containing B2L, B2, B3, A2L, A2, and A3 refrigerants as specified in 5.14
NOTE 3 A housing which is sufficiently large for people to enter is a machinery room.
Refrigerating equipment located in the occupied space
The requirements shall be as specified in EN 378-1.
Refrigerating equipment located in an unoccupied space not designated a
For underground systems utilizing class 3 flammable refrigerants with a charge exceeding 'm2', it is essential to install an additional gas detector along with an audible and visual alarm, ensuring compliance with the specified standards for detectors.
NOTE 2 Additional requirements may be needed for refrigerating systems containing B2L, B2, B3, A2L, A2, and A3 refrigerants as specified in 5.14
NOTE 3 A housing which is sufficiently large for people to enter is a machinery room
4.4Refrigerating equipment located in the occupied space
The requirements shall be as specified in EN 378-1
4.5 Refrigerating equipment located in an unoccupied space not designated a machinery room
Compressors or pressure vessels situated in a sealed, unoccupied area must be classified as a machinery room, as outlined in Clause 5.
In unoccupied spaces sealed from occupied areas, equipment with non-permanent joints must adhere to Clause 5 requirements If mechanical ventilation is necessary as per section 5.13, it should be provided by an extractor hood near the equipment, with a minimum ventilation rate of 0.05 m³/s per ventilator For equipment exposed to harsh conditions, such as severe vibrations or corrosive environments, the ventilation rate must increase to over 0.5 m³/s per extractor hood Additionally, refrigerant detectors should trigger ventilation at 50% of the ATEL, except for odorous refrigerants at concentrations below ATEL/ODL (like R-717) or at 25% of the LFL, whichever is lower.
NOTE 1 Severe vibration could be caused by unbalanced dynamic loads or hydraulic shock during defrost operation
NOTE 2 The ventilation rate is deemed sufficient to ventilate a volume of 18 m 3
If refrigerating equipment cannot be isolated from occupied areas, it must be treated as if it is located within those spaces, necessitating compliance with the applicable regulations for such environments.
Refrigerating equipment located in a ventilated enclosure within an occupied space
The refrigerating system's ventilated enclosure must include a manufacturer-specified ventilation duct, in accordance with EN 378-2 standards The installation room should have a volume at least ten times greater than that of the enclosure and provide adequate make-up air to compensate for any air that is exhausted Additionally, the enclosure's ventilation must direct air to the open environment.
Piping duct or shaft
Hand-operated shut-off devices installed in piping ducts or shafts intended for human entry must ensure multiple escape exits Additionally, these ducts should have a minimum height of 1.2 meters.
Access to machinery rooms
Machinery rooms must remain unoccupied except for authorized personnel performing essential maintenance Access should be restricted to trained individuals only If these rooms are utilized for extended periods, such as for building maintenance, they will be classified as occupied spaces under access category C, as outlined in EN 378-1.
A separate refrigeration machinery room shall not be used as an occupied space.
Venting from or through the machinery room
Refrigerant shall be prevented from entering neighbouring rooms, staircases, courts, gangways or building draining systems and the escaping gas shall be vented outdoors
There shall be no airflow to an occupied space through a machinery room unless the air is ducted and sealed to prevent any refrigerant leakage from entering the air stream.
Combustion equipment and air compressors
In machinery rooms housing combustion equipment or air compressors alongside refrigerating equipment, it is essential to duct the combustion air supply for engines or boilers, as well as the supply air for air compressors, from outside This setup must be designed to prevent any refrigerant from entering the air intake, ensuring safe and efficient operation.
Open flame
Open flames are prohibited in machinery rooms, except during welding, brazing, or similar activities, where monitoring of refrigerant concentration and adequate ventilation are required Additionally, open flames must not be left unattended.
Storage
Machinery rooms are designated solely for equipment use and must not serve as storage areas, except for tools, spare parts, and compressor oil related to the installed machinery Additionally, the storage of refrigerants, flammable, or toxic materials must comply with national regulations.
Remote emergency switch
A remote emergency switch for halting the refrigerating system must be installed outside the machinery room, close to the door Additionally, a similar switch should be positioned conveniently inside the room Both switches must comply with the emergency switch standards outlined in EN ISO 13850.
NOTE For gas fired refrigeration systems specific measures may be required including local regulations.
Exterior openings of the machinery room
Exterior openings shall not be situated within 2 m of building emergency exit staircases or other building openings, e.g windows, doors, ventilation inlets.
Piping and ducting
All piping and ventilation ducting that penetrates walls, ceilings, and floors in machinery rooms must be properly sealed This seal should possess a fire resistance rating that is at least equal to that of the surrounding walls, ceilings, or floors.
Discharge pipes from relief devices should effectively diffuse the charge into the air, ensuring that it is directed away from any air intakes of the building Additionally, the discharge should be managed in a manner that allows for an adequate quantity of suitable absorbing material to be utilized.
Relief devices for A1 group refrigerants may discharge into the machinery room if the system charge is below the limits specified in EN 378–1:2016, Annex C It is essential that these discharges occur in a manner that ensures the safety of individuals and property.
Normal lighting
When selecting fixed lighting for areas with refrigerating equipment, it is essential to ensure adequate illumination for safe operation, adhering to national regulations regarding illumination levels and placement Additionally, filament light bulbs in machinery rooms with R-717 refrigerating systems must be safeguarded with "splash safe" covers that meet the EN 60529 IPX 4 standard.
Emergency lighting
An emergency lighting system, whether fixed or portable, must be installed to ensure the operation of controls and safe evacuation of personnel during a power failure The system's illumination level and placement must comply with national regulations.
Dimensions and accessibility
The machinery room must be designed with adequate dimensions to facilitate the easy installation, operation, maintenance, repair, and disassembly of refrigerating equipment Additionally, it should provide sufficient space for personnel wearing personal protective equipment.
To ensure safety during the operation, maintenance, inspection, and repair of the refrigerating system, it is essential to provide catwalks and fixed ladders This prevents personnel from standing or walking on piping, fittings, their supports, and supporting structures.
Ensure a minimum headroom of 2.1 meters below equipment located over gangways and permanent work areas, in accordance with EN ISO 14122-2 standards Headroom is specifically defined as 2.1 meters above the walking surface.
Doors, walls and ducts
Doors and openings
Machinery rooms shall have doors opening outward and sufficient in number to ensure persons can escape in an emergency
The doors must be tightly fitted and self-closing, designed for easy opening from the inside to ensure safety in emergencies They should provide a minimum of one hour of fire resistance, constructed with materials tested according to EN 1634 standards Additionally, there should be no openings that allow the unintended escape of refrigerants, vapors, odors, or other gases into occupied areas.
Emergency
Provision shall be made to facilitate immediate exit from the machinery room in the event of an emergency
At least one emergency exit shall open directly to the open air or it shall lead to an emergency exit passageway.
Walls, floor and ceiling
The walls, floor, and ceiling separating the machinery room from the rest of the building must feature a minimum fire resistance rating of 1 hour and be securely sealed These components should be constructed from materials that comply with the standards set forth in EN 1363, EN 1364, and EN 1365.
NOTE Requirements regarding fire resistive construction of walls, doors, floor and ceiling may be provided in local regulations.
Service ducts
Service ducts must meet the standards set by EN 1366-1 and EN 1366-2, ensuring they are properly sealed to reduce refrigerant leakage Additionally, these ducts should possess fire resistance equivalent to that of walls and doors.
Service ducts and crawl spaces that house refrigerant piping must be properly vented to a safe location to avoid hazardous refrigerant buildup in case of a leak It is important to note that these service ducts should not be utilized for ventilation or conditioned air.
Ventilation ducts
Sheet metal used for both normal and emergency ventilation ducts must comply with EN 1507 and be supported according to EN 12236 To reduce gas leakage, all seams and joints of the ducts should be sealed after installation Additionally, the fire resistance of the ventilation duct must be at least equal to that of the doors and walls in the machinery room.
Ventilation
General
The ventilation of machinery rooms shall be sufficient both for normal operating conditions and emergencies
To ensure safety, air from machinery rooms must be vented outdoors through a dedicated mechanical ventilation system in the event of refrigerant leaks This ventilation system should operate independently from any other ventilation systems on the premises.
Provision shall be made for a sufficient supply of outside replacement air and a good distribution of that air over the machinery room avoiding dead zones
Openings for outside air shall be positioned to avoid re-circulation into the room.
Ventilation for normal operating conditions or when machinery room is occupied
Ventilation must comply with national regulations, ensuring a minimum of 4 air changes per hour when the machinery room is occupied If the required ventilation rate cannot be met, an audible and/or visual alarm will be activated, and electrical supplies may be disconnected as necessary.
Emergency mechanical ventilation
In the machinery room, gas detection is essential, and it must trigger the emergency mechanical ventilation system through designated detectors These detectors should comply with the specifications outlined in Clause 9.
Emergency mechanical ventilation shall be provided with two independent emergency controls one located outside the machinery room, and the other inside.
Required airflow for emergency mechanical ventilation
Airflow of the mechanical ventilation shall be at least the quantity obtained by Formula (1):
The air flow rate, denoted as \$V\$, is measured in cubic meters per second (m³/s) The mass of the refrigerant charge, represented as \$m\$, is expressed in kilograms (kg) and pertains to the refrigerating system with the largest charge, specifically any portion located within the machinery room.
0,014 is a conversion factor with units of m 3 /s kg 2/3
An emergency ventilation system with 15 air changes per hour is sufficient.
Mechanical ventilation openings
Mechanical ventilation openings must be strategically positioned and sized to ensure adequate airflow, taking into account the refrigerant's properties, the selection of intake or exhaust, and the ventilator's efficiency Additionally, the arrangement of these openings should facilitate the effective evacuation of refrigerant in all potential leak scenarios.
Machinery rooms for groups A2L, A2, A3, B2L, B2 and B3 refrigerants
General
Machinery rooms containing refrigerants classified as group A2L, A2, B2L, B2, A3, and B3 must undergo a flammability assessment and be classified according to EN 60079-10-1 for hazardous zones It is important to note that this assessment may determine that the hazardous area is negligible based on the lower flammability limit (LFL) and the type of release.
Refer to Clause 7 for requirements regarding electrical installation.
Location
The machinery room shall be located in accordance with local and national regulations
NOTE Requirements may depend on the amount of charge in the refrigerating system
The emergency exhaust ventilation fan shall be either: a) in the air flow with the motor outside the airflow, or b) rated for hazardous areas as required in EN 378-2:2016, 6.2.14
The fan shall be located to avoid pressurization of the exhaust ductwork in the machinery room
The fan shall not cause sparks to occur if it contacts the duct material
The exhaust ventilation outlet must comply with national regulations and should remain unobstructed to prevent the entry of debris, leaves, and birds Additionally, any vertical ductwork exposed to the outdoors must include a drain with a trap for rainwater, along with accessible inspection points.
Emergency ventilation must be activated when doors leading to other areas of the building are opened for more than 60 seconds, especially in locations where gas detectors cannot detect refrigerants.
Additional requirements for R-717
To prevent R-717 spills from contaminating surface waters, a catchment system must be designed and installed in compliance with national regulations Additionally, the machinery room floor should be constructed to contain any liquid R-717, ensuring it does not escape the room Furthermore, the drain from the catchment system should remain normally closed.
5.14.3.2 Specific equipment for emergency washing
For systems using R-717, it is essential to have readily available eye wash facilities, such as eye wash bottles Additionally, for systems with a refrigerant charge exceeding 1,000 kg, an emergency shower must be installed outside the machinery room's emergency exit, delivering a flow rate of at least 1 l/s at a temperature range of 25 °C to 30 °C.
Fire suppression systems using water sprinklers are not permitted in machinery rooms with R-717 refrigerating systems unless the machinery room meets all standard compliance requirements.
— the sprinkler heads are individually actuated at 141 °C or higher (high temperature according to
— there is no manual override of the activation of the sprinkler system;
— the sprinkler installation conforms to the requirements of EN 12845
NOTE 1 The addition of water to a pool of ammonia liquid can cause the rapid evolution of large amounts of ammonia gas in the atmosphere resulting in increased risk of injury to persons in the vicinity
NOTE 2 A pre-action system where an actuated water valve in the sprinkler supply is controlled by a fire detection system can be used to reduce the probability of accidental discharge of any of the sprinkler heads
NOTE 3 The provision for a remote sump in the drainage system from the machinery room will reduce the risk of environmental pollution from the run-off water.
Maximum surface temperature
Hot surfaces shall not exceed a temperature of 80 % of the auto-ignition temperature (in °C) or 100 K less than the auto-ignition temperature of the refrigerant, whichever is higher.
Doors and openings
Machinery rooms containing refrigerants classified as A2L, A2, A3, B2L, B2, or B3, and exceeding the practical charge limit for the room's volume, must feature a door that opens directly to the outside or through a dedicated vestibule with self-closing, tight-fitting doors.
General
These additional measures only apply to systems described in EN 378-1:2016, C.3
If an indoor unit or its piping is located in an occupied space with a volume that causes the total charge to exceed the limits set by EN 378-1:2016, C.3, alternative safety provisions outlined in Clause 6 can be implemented.
Occupied space
To prevent refrigerant stagnation in case of a leak, an indoor unit installed below 1.8 m must include a fan, circulator, or mechanical ventilation that operates continuously or activates via a detector If a dilution transfer opening, like a gap under the door, is present, low-level installation without air mixing is permissible.
The space where the indoor unit is installed shall be categorised as general access according to EN 378-
1 Indoor units shall not be used in a sealed room without ventilation to the outside of the room
The indoor equipment and pipes shall be securely mounted and guarded such as accidental rupture of equipment cannot occur, from such events as moving furniture or reconstruction activities.
Ventilation
General
EN 378-1:2016, C.3.2.2 and C.3.2.3, may require employing ventilation as a safety measure
Ventilation must be directed to areas with adequate air supply, such as outdoor spaces or large occupied rooms, to effectively dilute leaked refrigerants The indoor space designated for ventilation should possess sufficient volume, including that of the room housing the indoor unit, to ensure compliance with the quantity limit with minimum ventilation (QLMV) value It is essential that the total volume of the indoor area meets the QLMV requirements alongside the occupied space volume, while natural ventilation to the outdoors is not considered.
NOTE QLMV values can be found in EN 378–1:2016, Annex C and the limitations as in EN 378–1:2016, C.3 apply.
Dilution transfer openings (air transfer openings for dilution) for natural
Dilution transfer openings must be installed at both high and low levels, with the total area at each level meeting the requirements specified in Formula (2) These openings can be divided into multiple sections at each level, positioned close to the floor and ceiling If the ceiling is suspended and there is no wall separating the adjacent rooms above, the upper opening may be omitted.
A is the required opening area, expressed in m 2 ; m is the refrigerant charge, expressed in kg;
V is the room volume, expressed in m 3 ;
QLMV is the quantity limit with minimum ventilation as given in EN 378-1:2016, C.3.2 in kg/m 3
The lower edge of the lower opening must be at a height of 0.2 m or less from the floor, while the upper edge of the upper opening should be equal to or greater than the upper edge of the door opening.
Mechanical ventilation
For conditions where \$Q \times RCL/10 < 1\$, the mechanical ventilation must provide an actual airflow that meets the requirements of Formula (3) Conversely, when \$Q \times RCL/10 \geq 1\$, the airflow should be calculated based on Formula (4).
Q RCL (4) where m is the refrigerant charge in kg;
V is the room volume expressed in m 3 ;
10 is the expected maximum leak rate, in kg/h;
Q is the ventilation airflow in m 3 /h;
RCL is the refrigerant concentration limit in kg/m 3 , as given in ISO 817
NOTE “ln” means natural logarithm
Formula (5) presents a simplified calculation for airflow, which can be used in place of the previously obtained value However, this simplification results in a higher airflow value.
10 is the expected maximum leak rate, in kg/h;
Q is the ventilation airflow in m 3 /h;
RCL is the Refrigerant concentration limit in kg/m 3 , as given in ISO 817
The lower edge of the mechanical ventilation opening shall be as low as possible, and no higher than 0,2 m from the floor
Exhaust ventilation openings must be positioned at an adequate distance from intake openings to avoid recirculation into occupied areas Furthermore, the room should have openings that collectively match or exceed the area of the extract ventilation opening.
Mechanical ventilation shall be operated continuously or shall be switched on by the detector in accordance with Clause 9.
Safety shut off valves
General
Safety shut off valves must be installed in suitable locations within a refrigerating circuit, as mandated by EN 378-1:2016, C.3.2 These valves are crucial for preventing refrigerant leaks, ensuring that any leakage remains below the QLMV value in occupied areas.
According to EN 378-1:2016 and ISO 817, the RCL value should replace QLMV for the lowest underground floor of a building Valves must isolate the refrigeration circuit from occupied spaces, controlled by a detector as per Clause 9 The equipment manufacturer or installer is responsible for providing data to calculate potential refrigerant leakage into occupied areas, including the leak amount based on sensor response time and the refrigerant remaining in the system after valve closure This information, which must also detail the valve locations and detector positions, should be included in the installation documentation as specified in EN 378-2:2016, 6.4.3.1.
Location
Shut off valves shall be located outside of the occupied space and shall be positioned to enable access for maintenance by an authorised person.
Design
Valves shall be designed to close in the event of an electric power failure e.g spring return solenoid valves
Valves in the refrigeration circuit must effectively stop refrigerant flow during a leak while ensuring that normal refrigerant flow remains largely unaffected.
General requirements
The general electrical installation of the refrigerating and other equipment including lighting, power, etc., shall conform to national regulations and the provisions in series IEC 60364 as appropriate
NOTE Additional guidance can be found in IEC/TR 61200–52.
Main power supply
The electrical power supply for a refrigerating system must be designed to allow independent disconnection from other electrical equipment, including lighting, ventilation, alarms, and safety systems The main power supply connection to the refrigerating machinery should comply with EN 60204-1:2006, specifically Clauses 4 and 5.
Electrical equipment in machinery rooms with refrigerating systems containing
Electrical equipment shall be selected to be suitable for use in the zones identified in 5.14.1
For 2L refrigerants, electrical equipment is considered compliant if the electrical supply is disconnected when the refrigerant concentration is at or below 25% of the lower flammable limit Equipment that remains operational when refrigerant levels surpass the main alarm threshold, such as alarms, gas detectors, ventilation fans, and emergency lighting, must be designed for use in hazardous areas.
This clause applies to all electrical equipment and power supplies in the room, not only the refrigerating system
General
Alarms must be installed to detect refrigerant leaks in machinery rooms or occupied spaces, activating in accordance with section 8.3 These alarms will be triggered by signals from detectors as specified in Clause 9, ensuring that authorized personnel are alerted to take necessary actions.
Alarm system power
When an alarm system is installed, it must be powered by a source that is independent of the mechanical ventilation or refrigeration systems it is designed to protect.
NOTE Back up power using batteries can be used for the alarm system.
Alarm system warning
The alarm system shall warn both audibly and visibly such as both a loud (15 dB(A) above the background level) buzzer and a flashing lamp
For a machinery room the alarm system shall warn both inside and outside the machinery room The alarm outside the machinery room may be installed in a supervised location
For an occupied space the alarm system shall warn at least inside the occupied space
For access category a (see EN 378-1) the alarm system shall also warn at a supervised location such as the night porter’s location as well as the occupied space.
Additional alarm system requirements for R-717 systems with charges above
The owner of the refrigerating system must establish a continuously monitored central alarm station Specialized personnel should be on-site within 60 minutes of an alarm, and they can also receive notifications through technical devices such as mobile phones or pagers.
General
When refrigerant concentration surpasses the practical limit set by EN 378-1:2016, Annex C, detectors must trigger an alarm and activate emergency mechanical ventilation in the machinery room Compliance with the specifications outlined in sections 9.2 to 9.4 is essential.
Location of detectors
The location of detectors shall be chosen in relation to the refrigerant and they shall be located where the refrigerant from the leak will concentrate
When positioning the detector, it is essential to consider local airflow patterns, including the sources of ventilation and louvers Additionally, potential risks of mechanical damage or contamination must be taken into account.
Each machinery room or occupied space must have at least one detector installed, with specific placement depending on the type of refrigerant used: for refrigerants heavier than air, the detector should be located in the lowest underground room, while for lighter-than-air refrigerants, it should be positioned at the highest point.
Type and performance of detectors
General
A compatible detector must provide an electrical signal when the refrigerant or oxygen concentration reaches a predetermined level, triggering the shut-off valves, alarm system, mechanical ventilation, or other emergency controls.
Detectors shall be continuously monitored for functioning In the case of a detector failure, the emergency sequence should be activated as if refrigerant had been detected
The pre-set value for the refrigerant detector at 30 °C or 0 °C, whichever is more critical, shall be set to
According to EN 378-1:2016, Annex E, the oxygen deprivation detector must be set to a pre-determined value of 18% or higher, with the applicable limit being 25% of the LFL or 50% of the ATEL/ODL, whichever is lower.
When designing a detector, it is crucial to account for its sensitivity tolerance to ensure that the output signal activates at or below the predetermined threshold Additionally, the detector's tolerance must consider a ± 10% variation in power line voltage.
An appropriate maintenance period shall be established for each type of detector used
Oxygen deprivation sensors shall only be used for with systems containing A1 refrigerants except for R-
Detectors used for monitoring halogenated refrigerants must adhere to the EN 14624 standard Furthermore, all detectors should have a response time of 30 seconds or less when exposed to a concentration of 1.6 times the preset value.
NOTE 1 Sensors may be affected by the presence of gas or vapour other than that the equipment is intended to detect Ensure that if sensors are used, this will not compromise the safety or integrity of the installation
NOTE 2 EN 60079–29–2 specifies requirements for selection, installation, use and maintenance of detectors of flammable gases.
Refrigerant detectors for A2, A2L, B2L (except for R-717), B2, A3 and B3 refrigerants
A refrigerant detector designed for group A2L, A2, B2L (excluding R-717), B2, A3, and B3 refrigerants must trigger an alarm when concentrations reach 25% of the refrigerant's lower flammability limit (LFL) The detector will maintain alarm activation at higher concentration levels and should be calibrated to activate at lower levels for toxic refrigerants, if relevant Upon activation, the system will automatically sound an alarm, initiate mechanical ventilation, and shut down the system.
R-717 detectors
To mitigate the risks of explosion or fire in machinery rooms, it is essential to install an R-717 detector when the charge size exceeds 50 kg This detector must operate at a concentration that does not exceed specified limits.
— 350 mg/m 3 (volume fraction of 500 × 10 −6 ) (pre-alarm);
— 21 200 mg/m 3 (volume fraction of 30 000 × 10 −6 ) (main alarm)
At the pre-alarm level, an alarm and the mechanical ventilation shall be activated
At the main alarm level,
— the refrigerating system shall be stopped automatically;
— the power supply to the machinery rooms shall be isolated automatically;
— the mechanical ventilation shall be stopped if appropriate provisions are not made (see 5.14.2.2)
In machinery rooms containing only compressors or compressor units, it is essential to install at least one detector above these units Additionally, refrigerant pumps, whether located in the machinery room or other areas, must be monitored by a detector positioned above and in close proximity to the pumps.
Detectors shall be suitable for their use and calibrated by a competent organization
R-717 detectors must be integrated into the heat transfer circuit of indirect systems, such as water or glycol circuits, to monitor and identify any refrigerant presence when the R-717 charge exceeds a specified level.
Detectors must be installed to monitor for 500 kg of refrigerant, as specified in EN 378-2:2016, section 6.2.6.8 These devices are designed to activate an alarm within the machinery room and, if feasible, in the control system operator interface However, they should not trigger beacons, klaxons, or initiate any evacuation procedures.
Installation
The installation of the detector shall allow access for checking, repair or replacement by an authorized person
The detector shall be installed so its function can be verified easily
The detector shall be protected to prevent tampering or unauthorised resetting of the pre-set value
10 Instruction manuals, notices and inspections
Instruction manual
The installation instructions must clearly outline the emergency procedures for the building in case the alarm system is activated Designated authorized personnel for the machinery room and each occupied area should be familiar with these procedures and possess the authority to implement them.
NOTE Requirements for instructions for refrigerating systems are given in EN 378–2.
Warning notice
Machinery rooms must be clearly labeled at their entrances, accompanied by warning signs indicating that unauthorized access is prohibited and that smoking, open flames, or naked lights are not allowed Furthermore, additional warning notices should be posted to prevent unauthorized operation of the system.
A clearly visible notice outlining the emergency procedures must be displayed in occupied spaces, indicating that only authorized personnel familiar with these procedures may enter the machinery room during an emergency Additionally, refrigerating systems containing over 10 kg of A3 and B3 refrigerants in open areas must have marked entrances to restricted zones, accompanied by warning signs prohibiting unauthorized access, smoking, naked flames, and other ignition sources.
Visual inspection of the site
Before handing over the installation site to the owner, it is essential to verify that all services and equipment related to the refrigerating system are properly installed and operational Key checks include ensuring that escape and access routes are unobstructed, ventilation openings are clear, mechanical ventilation in the machinery room is functional, refrigerant detectors are in place, alarms and backup power systems are operational as needed, emergency lighting is available, and personal protective equipment is accessible.
These shall be documented after commissioning.
Maintenance of the site
Users or their authorized representatives must conduct annual checks of alarms, mechanical ventilation, and detectors to ensure proper functionality It is essential to inspect dilution transfer openings between rooms in occupied spaces for any obstructions that may hinder airflow Additionally, a logbook should be maintained to record the results of these inspections.
NOTE For maintenance of the refrigerating system see EN 378–4
11 Heat sources and temporary high temperatures at the site
To prevent excessive heat exposure that can lead to high pressure, it is essential to implement effective measures when installing evaporators or air coolers near heat sources.
Condensers and receivers shall not be located in the proximity of heat sources
Refrigerant-containing components must be designed to allow liquid refrigerant to escape to cooler areas of the system if they exceed the maximum allowable pressure due to high temperatures, such as those caused by electrical defrosting, hot water defrosting, or cleaning with hot water or steam.
NOTE If necessary, the system can be equipped with a receiver, which is permanently connected to the apparatus in question (See EN 378–2)
General requirements
Type of protective equipment
Personal protective equipment agreed by the local rescue services and appropriate to the quantity and type of refrigerant should be readily available.
Accessibility
The equipment for personal safety should be readily accessible.
Location
Personal safety equipment must be strategically placed to avoid interference, ideally positioned outside the room where refrigerants may leak, yet close to the room's entrance for easy access.
Check and maintenance
Regular inspection and maintenance of personal protective equipment and emergency gear are essential, following the manufacturer's guidelines Any identified defects or deficiencies must be addressed immediately by replacing the equipment.
The quantity and types of personal protective equipment (PPE) and emergency gear should be coordinated with the local rescue service, such as the fire brigade, to determine the necessary respiratory protective devices.
During planned maintenance of refrigerating systems the equipment for personal safety should be agreed, provided and maintained by the maintenance company.
Temperature
Respiratory protective devices should be suitable for use at a temperature down to the temperature achieved by the system or ambient climate conditions depending on the application.
Respirators
Filter protection respirators must be compatible with the refrigerant in use and effectively protect against any decomposition products that may be generated by exposure to naked flames or fire.
Spare filter inserts should always be available
Face mask or gas masks are not allowed to be used for refrigerants which suppress the content of oxygen e.g CFC/HCFC/HFCs, HCs and R-744
Filter inserts are usually identified by a colour code and a character code for the vapour in question (see EN 14387)
A respirator must be properly fitted to the individual expected to use it, ensuring they are well-trained in its operation Regular and comprehensive instruction on the correct use of the respirator is essential for all personnel.
In refrigerating systems with multiple operators, it is essential that each individual has access to a suitable respirator that they are well-acquainted with.
To ensure optimal performance, respiratory protective devices must be maintained according to the manufacturer's guidelines and regularly inspected, even if they have not been used It is essential to record the duration of use for respirators equipped with filter inserts and to replace the inserts as needed Additionally, the procurement date of new inserts should be documented.
Normal use
Personal protective equipment should be provided for use by every person doing maintenance, repair and recovery as follows: a) for all refrigerants and irrespective of the properties of the refrigerant:
— protective gloves and protection for eyes; b) for R-717:
— respiratory protection devices in accordance with EN 132, EN 133, EN 134, EN 135, EN 136,
When welding or brazing in the presence of group A1 refrigerants, it is essential to use a filter protection respirator equipped with a filter insert specifically designed to protect against decomposition products.
Emergency use
General
Equipment for emergency use should be provided as follows:
— respiratory protective devices in accordance with EN 132, EN 133, EN 134, EN 136, EN 137,
— filter protection respirator (full face mask) or a self-contained breathing apparatus.
Respiratory protective devices
Respiratory protective devices must be compatible with the specific refrigerant in use If self-contained breathing apparatus is available on-site, it should be regularly maintained by qualified personnel and used exclusively by trained individuals who are knowledgeable about the specific brand and model of the equipment.
First aid equipment
First aid supplies, medications, and specific chemicals associated with the refrigerants in use, along with protective blankets, must be readily accessible and stored outside the machinery room, close to its entrance.
Special attention should be paid to equipment for rapid treatment of eye injuries
Medicines and other chemicals in the first aid equipment should be provided only after consultation with medical experts
[1] EN 132, Respiratory protective devices — Definitions of terms and pictograms
[2] EN 133, Respiratory protective devices — Classification
[3] EN 134, Respiratory protective devices — Nomenclature of components
[4] EN 135, Respiratory protective devices — List of equivalent terms
[5] EN 136, Respiratory protective devices — Full face masks - Requirements, testing, marking
[6] EN 137, Respiratory protective devices — Self-contained open-circuit compressed air breathing apparatus with full face mask — Requirements, testing, marking
[7] EN 378-4, Refrigerating systems and heat pumps — Safety and environmental requirements —
Part 4: Operation, maintenance, repair and recovery
[8] EN 14387, Respiratory protective devices — Gas filter(s) and combined filter(s) — Requirements, testing, marking
[9] EN 14593-1, Respiratory protective devices — Compressed air line breathing apparatus with demand valve — Part 1: Apparatus with a full face mask - Requirements, testing, marking
[10] EN 14593-2, Respiratory protective devices — Compressed air line breathing apparatus with demand valve — Part 2: Apparatus with a half mask at positive pressure — Requirements, testing, marking
[11] EN 14594, Respiratory protective devices — Continuous flow compressed air line breathing apparatus — Requirements, testing, marking
[12] EN 60079-0, Explosive atmospheres — Part 0: Equipment — General requirements (IEC 60079-0)
[13] EN 60079-29-2, Explosive atmospheres — Part 29-2: Gas detectors — Selection, installation, use and maintenance of detectors for flammable gases and oxygen (IEC 60079-29-2)
[14] IEC/TR 61200-52, Electrical installation guide — Part 52: Selection and erection of electrical equipment — Wiring systems