Draft Details
- Mechanical refrigeration code (Amendment)
- DRAFT STANDARD
- Legal Notice for Draft Standards
- Preface
- + 1 Scope
- 1.1 Purpose
- + 1.2 Application
- 1.2.1
- 1.2.2
- 1.2.3
- 1.3 Terminology
- 1.4 Units of measurement
- 2 Reference publications
- + 3 Definitions and abbreviations
- 3.1 Definitions
- 3.2 Abbreviations
- + 4 System selection and application requirements...
- 4.1 Application procedure
- + 4.2 Classification by occupancy
- 4.2.1 General
- 4.2.2 Institutional occupancy
- 4.2.3 Public assembly occupancy
- 4.2.4 Residential occupancy
- 4.2.5 Commercial occupancy
- 4.2.6 Industrial occupancy
- 4.2.7 Mixed occupancy
- 4.2.8 Adjacent locations
- + 4.3 Classification of refrigeration systems
- + 4.3.1 Classification by type
- 4.3.1.1 General
- + 4.3.1.2 Direct system
- 4.3.1.2.1 General
- 4.3.1.2.2 Double direct system
- 4.3.1.2.3 Volatile direct system
- 4.3.1.3 Indirect system
- 4.3.2 Classification by leakage probability
- + 4.4 Classification by refrigerant
- 4.4.1 Safety groups
- 4.4.2 Refrigerant data
- 4.4.3 Refrigerant classification notes
- + 4.5 System application requirements
- 4.5.1 Overview
- + 4.5.2 Application restrictions by refrigerant s...
- 4.5.2.1 General
- 4.5.2.2 Refrigeration systems for high-probabil...
- 4.5.2.3 Refrigeration systems other than human ...
- 4.5.2.4 Higher-flammability refrigerants
- 4.5.3 Effective dispersal volume
- + 4.5.4 System refrigerant charge limits
- 4.5.4.1 System refrigerant charge limit determi...
- 4.5.4.2 Institutional occupancy refrigerant sys...
- 4.5.4.3 Flammable refrigerants (A2, A3, B2, B3)...
- Figure 7 a)
- Figure 7 b)
- 4.5.4.4 EDVC calculation
- 4.5.4.5 Releasable refrigerant charge (mrel) de...
- 4.5.4.6 Release mitigation controls (safety shu...
- + 4.5.5 High-probability systems using A2L refrig...
- 4.5.5.1 General
- 4.5.5.2 Refrigeration systems with air circulat...
- 4.5.5.3 Other high-probability human comfort re...
- Table 1
- Table 2
- Table 3
- 4.5.5.4 Certification, installation, and identi...
- 4.5.5.5 Manufacturer’s refrigerant detection sy...
- 4.5.5.6 Ignition sources and hot surfaces locat...
- 4.5.5.7 Mechanical ventilation
- + 4.5.6 High-probability systems using A2L refrig...
- 4.5.6.1 General
- + 4.5.6.2 System refrigerant charge limits
- 4.5.6.2.1
- 4.5.6.2.2
- 4.5.6.3 Calculated system refrigerant charge li...
- 4.5.6.4 Certification, installation, and identi...
- 4.5.6.5 Refrigerant detector
- 4.5.6.6 Ignition sources located in ductwork
- 4.5.6.7 Compressors and pressure vessels locate...
- 4.5.7 High-probability systems using A2 refrige...
- + 4.5.8 Equipment location and installation requi...
- 4.5.8.1 Public stairway, stair landing, or exit...
- 4.5.8.2 Public hallway or lobby
- 4.5.8.3 Corridors and lobbies
- 4.5.8.4 Industrial occupancies and refrigerated...
- + 4.5.8.5 Location in a machinery room or outdoor...
- 4.5.8.5.1
- 4.5.8.5.2
- 4.5.8.6 Addition of doors to open refrigerated ...
- + 4.5.9 Refrigerant quality
- 4.5.9.1 General
- 4.5.9.2 Refrigerant type and purity
- 4.5.9.3 Recovered refrigerants
- 4.5.9.4 Recycled refrigerants
- 4.5.9.5 Reclaimed refrigerants
- 4.5.9.6 Mixing of refrigerants
- 4.5.9.7 Refrigerant or lubricant conversion
- + 5 Equipment design and construction
- + 5.1 Drawings, specifications, and data reports
- 5.1.1
- 5.1.2
- 5.1.3
- 5.2 Certified factory assembled refrigeration s...
- + 5.3 Filing of drawings
- 5.3.1 Submission of drawings and specifications...
- 5.3.2 Contents of drawings
- + 5.4 Materials
- 5.4.1
- 5.4.2
- 5.4.3
- + 5.5 Design pressures
- 5.5.1
- 5.5.2
- 5.5.3
- 5.5.4
- 5.5.5
- 5.5.6
- 5.5.7
- 5.5.8
- + 5.6 Refrigerant-containing pressure vessels
- + 5.6.1
- 5.6.1.1
- 5.6.1.2
- + 5.6.2
- 5.6.2.1
- 5.6.2.2
- + 5.6.3
- 5.6.3.1
- 5.6.3.2
- + 5.7 Refrigerant piping, fittings, evaporator an...
- 5.7.1 Refrigerant piping and fittings
- + 5.7.2 Minimum requirements for unprotected refr...
- 5.7.2.1
- 5.7.2.2
- 5.7.2.3
- 5.7.3 Evaporator and condenser coils and associ...
- + 5.8 Components other than pressure vessels, pip...
- 5.8.1
- 5.8.2
- 5.8.3
- + 5.9 Design provisions for service
- 5.9.1
- + 5.9.2
- 5.9.2.1
- 5.9.2.2
- + 5.9.3
- 5.9.3.1
- 5.9.3.2
- 5.9.4
- 5.9.5
- + 5.10 Pressure testing
- 5.10.1 General
- + 5.10.2 Test medium
- 5.10.2.1
- 5.10.2.2
- + 5.10.3 Factory tests
- 5.10.3.1
- 5.10.3.2
- 5.10.3.3
- 5.10.3.4
- + 5.10.4 Field tests
- 5.10.4.1
- 5.10.4.2
- 5.10.4.3
- 5.10.4.4
- 5.10.4.5
- + 5.11 Marking and labelling
- 5.11.1 Nameplates for certified and unit system...
- 5.11.2 Additional signs for refrigeration syste...
- 5.11.3 Signs for systems containing more than 4...
- 5.11.4 New signs for changed refrigerant
- 5.11.5 Posting of instructions
- 5.12 Substitution of refrigerant type
- 5.13 Secondary coolant systems
- + 6 Installation
- + 6.1 General
- 6.1.1
- 6.1.2
- 6.1.3
- 6.1.4
- + 6.2 Machinery rooms
- 6.2.1 General
- + 6.2.2 Doors and vestibules
- 6.2.2.1 General
- 6.2.2.2 Door features
- 6.2.2.3 Vestibules
- 6.2.2.4 Additional requirements for A2, B2, A3,...
- 6.2.2.5 Additional requirements for B1 refriger...
- 6.2.3 Refrigerant vapour detector
- + 6.2.4 Explosion protection
- 6.2.4.1
- 6.2.4.2
- 6.2.4.3
- + 6.2.5 Ventilation
- 6.2.5.1 General
- 6.2.5.2 Ventilation fans
- 6.2.5.3 Location of air inlets, the provision o...
- 6.2.5.4 Fan switches
- + 6.2.5.5 Mechanical ventilation
- 6.2.5.5.1 Leaks or ruptures calculation
- 6.2.5.5.2 Minimum ventilation
- 6.2.5.6 Natural ventilation calculation
- 6.2.5.7 Minimum temperature
- 6.2.5.8 Air to or from an occupied space
- + 6.3 Machinery rooms for flammable refrigerants ...
- + 6.3.1 Flammable refrigerant machinery rooms
- 6.3.1.1 General
- + 6.3.1.2 Eyewash and safety shower unit for ammo...
- 6.3.1.2.1 General
- 6.3.1.2.2 Inside machinery rooms
- 6.3.1.2.3 Outside machinery rooms
- + 6.3.2 Special requirements for machinery rooms ...
- 6.3.2.1 Refrigerant detector location
- 6.3.2.2 Refrigerant detector conditions
- 6.3.2.3 Alarm requirements — Set points, respon...
- + 6.3.2.4 Ventilation
- 6.3.2.4.1 General requirements
- 6.3.2.4.2 Level 1 ventilation for Class 2L refr...
- 6.3.2.4.3 Level 2 ventilation for Class 2L refr...
- 6.3.2.4.4 Airflow requirement for Level 2 venti...
- 6.4 Machinery rooms — Electrical requirements f...
- + 6.5 Water supply and discharge connections
- 6.5.1
- 6.5.2
- 6.6 Electrical wiring
- 6.7 Gas devices
- + 6.8 Location of refrigerant piping
- 6.8.1
- 6.8.2
- 6.8.3
- 6.8.4
- 6.8.5
- 6.9 Joints and refrigerant-containing parts in ...
- 6.10 Emergency discharge
- 6.11 Purge discharge
- + 7 Overpressure protection
- + 7.1 Pressure vessel protection
- 7.1.1 ASME Boiler and Pressure Vessel Code requ...
- 7.1.2 Pressure vessels with an internal gross v...
- + 7.1.3 Pressure vessels with an internal gross v...
- 7.1.3.1 General
- 7.1.3.2 Pressure vessels with an internal gross...
- + 7.1.3.3 Pressure vessels with an internal gross...
- 7.1.3.3.1 General
- 7.1.3.3.2 Pressure-relief valves discharging in...
- 7.1.3.3.3 Pressure-relief devices in parallel o...
- 7.1.4 Pressure-relief devices for pressure vess...
- + 7.2 System protection
- 7.2.1 Pressure-limiting devices
- + 7.2.2 Setting of pressure-limiting devices
- 7.2.2.1
- 7.2.2.2
- 7.2.2.3
- 7.2.2.4
- + 7.2.3 Pressure-imposing device protection
- + 7.2.3.1 Positive-displacement compressor
- 7.2.3.1.1
- 7.2.3.1.2
- 7.2.3.1.3
- + 7.2.3.2 Liquid refrigerant pump protection
- 7.2.3.2.1
- 7.2.3.2.2
- + 7.2.4 Hydrostatic expansion
- 7.2.4.1
- 7.2.4.2
- 7.2.4.3
- + 7.3 Pressure-relief devices
- + 7.3.1 General
- 7.3.1.1
- 7.3.1.2
- 7.3.1.3
- + 7.3.2 Location of pressure-relief devices
- 7.3.2.1
- 7.3.2.2
- + 7.3.3 Setting of pressure-relief devices
- 7.3.3.1 Pressure-relief valve setting
- 7.3.3.2 Rupture member setting
- + 7.3.4 Capacity of pressure-relief devices
- 7.3.4.1 Required capacity
- + 7.3.4.2 Rated discharge capacity
- 7.3.4.2.1
- 7.3.4.2.2
- + 7.3.5 Marking of fusible plugs and other pressu...
- 7.3.5.1
- 7.3.5.2
- 7.3.5.3
- + 7.3.6 Discharge of fusible plugs and other pres...
- + 7.3.6.1
- 7.3.6.1.1
- 7.3.6.1.2
- 7.3.6.1.3
- 7.3.6.2
- 7.3.6.3
- 7.3.6.4
- 7.3.6.5
- Table 6
- Table 7
- + 8 Maintenance of systems
- + 8.1 Charging and withdrawal of refrigerants
- 8.1.1 General
- 8.1.2 Charging R-744 systems
- 8.1.3 Charging or withdrawal of refrigerants in...
- + 8.2 Refrigerants withdrawn from refrigeration s...
- 8.2.1 Refrigerant container filling weight
- 8.2.2 Secondary refrigerants and lubricants wit...
- 8.3 Refrigerant storage
- + 8.4 Maintenance
- 8.4.1
- 8.4.2
- 8.4.3
- 8.4.4
- 8.4.5
- + 9 Precautions
- + 9.1 Protective equipment
- 9.1.1
- 9.1.2
- 9.2 Enclosed spaces
- 9.3 Decommissioning
- + Annex A (informative)
- Maximum allowable concentration of mixtures
- A.1
- + Annex B (informative)
- Guidelines for emergency discharge of refriger...
- B.1
- B.2
- B.2.1
- B.2.2
- B.2.3
- B.2.4
- B.2.5
- B.2.6
- B.2.7
- B.2.8
- B.2.9
- + Annex C
- Reserved
- + Annex D (informative)
- Conversion factors
- D.1
- + Annex E (informative)
- A method for calculating the discharge capacit...
- E.1 Calculation method
- E.2 Example
- + Annex F
- Reserved
- + Annex G
- Reserved
- + Annex H (normative)
- Allowable equivalent length of discharge pipin...
- H.1
- H.2
- + Annex I
- Reserved
- + Annex J (normative)
- Working with R-744 (CO2) systems — Precautions...
- J.1 Oil, oxygen, and moisture in R-744 refriger...
- J.2 Reaction of R-744 with ammonia
- J.3 R-744 refrigerant handling precautions duri...
- J.4 Auxiliary power supply
- J.5 Potential hazards
- J.5.1
- J.5.2
- J.5.3
- J.5.4
- J.5.5
- J.5.6
- + Annex K (informative)
- Characteristics of carbon dioxide
- K.1
- K.2
- + Annex L (normative)
- Infrequently used refrigerants — Design pressu...
- Table L.1
- Table L.2
- + Annex M (normative)
- Frequently used refrigerants
- M.1 General
- Table M.1
- Table M.2
- Table M.3
- + Annex N (normative)
- Effective dispersal volume calculations
- N.1 Room volume
- N.1.1 Overview
- N.1.2 Exempted spaces
- N.2 Connected spaces by natural ventilation
- N.2.1 General
- N.2.2 Natural ventilation opening for Group A1 ...
- N.2.3 Natural ventilation opening for Group A2L...
- N.3 Connected spaces via ducted air distributio...
- N.3.1 General
- N.3.2 Closures
- N.3.3 Plenums
- N.3.4 Supply and return ducts
- N.4 Connected spaces by mechanical ventilation
- N.4.1 General
- N.4.2 Ductwork
- + Annex O (normative)
- Releasable refrigerant charge calculation
- O.1 Releasable refrigerant charge calculation
- + Annex P (normative)
- Manufacturer’s refrigerant detection system re...
- P.1 Detection system requirements
- P.2 Mitigation action requirements
- + Annex Q (normative)
- Mechanical ventilation for high-probability sy...
- Q.1 Mechanical ventilation calculations using T...
- Q.2 Alternative calculations for refrigerants n...
- Table Q.1
- Table Q.2
- Q.3 Continuous ventilation or refrigerant detec...
- Q.3.1 Overview
- Q.3.2 Refrigerant detector activated ventilatio...
- Q.3.3 Verification of ventilation function
- Q.4 Makeup air
- Q.5 Refrigerant concentration
- Q.6 Ignition sources and hot surfaces located i...
- Q.7 Equipment criteria
1.1 Purpose
The purpose of this Standard is to minimize the risk of personal injury by providing minimum requirements for the design, construction, installation, inspection, and maintenance of the mechanical refrigeration systems and volatile direct refrigeration systems specified in Clauses 1.2.1 and 1.2.2.
Note: This Standard does not directly address protection of property and preservation of the environment.
1.2 Application
1.2.1
Except as specified in Clause 1.2.3, this Standard applies to the design, construction, installation, inspection, and maintenance of every refrigeration system as provided for by the “Act” (as defined in Clause 3) and identified in this Standard.
1.2.2
This Standard applies to
all refrigeration systems installed subsequent to its adoption. This includes refrigeration systems installed in a new or existing premises. It also applies to all premises, including the machinery room if required, in which a refrigeration system is to be installed;
refrigeration systems that undergo a substitution of refrigerant in a premises defined in Item a); and
those parts of a refrigeration system that are replaced in, or added to, systems installed prior to its adoption.
Note: When adding or replacing parts [see Item c)], consideration should be given to the premises requirements of Item a).
1.2.3
This Standard does not apply to the following:
the use of water or air as a refrigerant;
bulk-storage gas tanks not permanently connected to a refrigeration system; and
refrigeration systems installed on railroad cars, motor vehicles, motor-drawn vehicles, aircraft, or ships.
1.3 Terminology
In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
1.4 Units of measurement
The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only. A list of conversion factors is provided in Annex D.
Pressure, unless otherwise stated, is expressed in kilopascals above atmospheric pressure, i.e., gauge pressure.
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