AS/NZS/ISO 817 and AS/NZS REFRIGERATION IMPACTS

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1 AS/NZS/ISO 817 and AS/NZS REFRIGERATION IMPACTS Ben Adamson F.AIRAH, F.IEAUST, M.ASHRAE, M.IIAR Managing Director, Refrigeration Engineering International

2 Refrigeration Standards Update Safety and Environmental Requirements AS/NZS ISO 817 and AS/NZS 5149 (Part 1 to Part 4) AIRAH Qld Seminar 14 th Feb Kevin Lee Former Chair ME-006 & Australian Delegate on ISO TC86/SC1

3 Refrigerant classification 16 pages 66 refrigerants classified 71 pages 109 refrigerants classified

4 Refrigerant classification AS Last amended 2000 Toxicity class A & B Flammability class 1, 2, 3 AS/NZS ISO Toxicity class A & B Flammability class 1, 2, 2L, 3

5 Flammability class 2L New class 2L lower flammability 2L is based on burning velocity R32 moves from A2 to A2L Ammonia (R717) moves from B2 to B2L Many new HFO refrigerants are A2L, for example R1234yf

6 Toxicity Preface This Standard does not address the hazards caused by products of combustion or decomposition of refrigerants. When flammable fluorinated refrigerants burn or decompose, by-products can include highly toxic compounds including hydrogen fluoride. STEL 2-6 ppmv IDLH 30 ppmv

7 Safety classification groups Safety group Higher flammability A3 B3 Flammable A2 B2 Lower flammability A2L B2L No flame propagation A1 Lower toxicity B1 Higher toxicity

8 Odorizing AS/NZS Required Group A3 refrigerants to be odourised. AS/NZS ISO 817 Does not require Group A3 refrigerants to be odourised. Most imported equipment with A3 refrigerants are not odourised. Personal sensitivity to odourants is not consistent Odourant effectiveness can be reduced by filter-driers etc.

9 Safety & environmental requirements 56 pages 166 pages (in 4 parts)

10 AS/NZS 5149 Parts 1-4 Part 1: Definitions, classification and selection criteria Part 2: Design, construction, testing, marking and documentation Part 3: Installation site Part 4: Operation, maintenance, repair and recovery

11 Scope This International Standard specifies the requirements for the safety of persons and property, provides guidance for the protection of the environment, and establishes procedures for the operation, maintenance, and repair of refrigerating systems and the recovery of refrigerants.

12 Australian & NZ amendments (all parts) Amendments not indicated in main text Australian & NZ amendments included in Appendix ZZ Performance clause permits alternatives which are - no less safe - verified by a competent person

13 Part 1: Definitions, classification and selection criteria

14 Occupancy categories General occupancy a (equiv. AS cat. I) Example hospitals, schools, supermarkets Supervised occupancy b (equiv.as cat. II) Example offices, work places Authorised occupancy c (equiv.as cat. III) Examples oil refineries, cold stores, non-public areas of supermarkets (Appendix ZZ classifies machinery rooms as Authorised occupancy c.)

15 Location classifications (new) Both occupancy & location classifications used in charge limits Class I: mech. equipment in occupied space (eg. self-contained drinks cabinet in a shop) Class II: compr s in machinery room or open air (eg. cold store, air con split system) Class III: machinery room or open air (eg. water-cooled or air-cooled package chiller) Class IV: ventilated enclosures

16 Charge limits Significant changes, especially for flammables Seven useful calculation examples provided in Australian & NZ appendix ZA

17 Charge limits The refrigerant quantity is the quantity that can be released in an occupied space, and shall be the largest charge of any single refrigerating system, unless otherwise specified If the required charge will exceed the permissible limit, several smaller individual units, each with a charge below the limit but in total exceeding the limit, are permitted.

18 Cap factors Cap factors apply to limit charges for flammables Same as AS except propane in human comfort applications (but already limited by appliance standard.) Appliance standards generally overrule AS/NZS 5149.

19 Relation to ADG code AS/NZS/ISO 817 and ADG code use different definitions of flammable Appendix ZB shows relation between AS/NZS/ISO 817 and ADG code for many common refrigerants Example R1234ze - ISO 817 = A2L - ADG code = non-flammable

20 Part 2: Design, construction, testing, marking and documentation

21 Design temperatures AS Two DBT ranges, 30 C, 43 C Air-cooled DBT C Water/evap. cooled - WBT C AS/NZS Four DBT ranges, 32 C, 38 C, 43 C, 55 C Margins generally > AS1677.2

22 A2L refrigerants Clause 4.1 The same requirements as class 2 shall be applied to class 2L, unless specific provisions are given in this part of ISO 5149.

23 Flow charts for relief sizing More user-friendly than AS Aligns with AS4343 Pressure equipment hazard levels

24 Other useful information Annex B ammonia systems Annexes E & F pressure relief arrangements Annex G Stress corrosion cracking

25 Part 3: Installation site

26 Australian & NZ modifications Substantial changes to ISO text Machinery rooms with flammable refrigerants (including A2L) require hazard assessment to AS Special provisions in AS for ammonia (B2L) do not apply to A2L. Sprinkler systems permitted in ammonia machinery rooms.

27 Australian & NZ modifications Clause 4.2 (ZZ addition) Any equipment in the open air (location Classifications II and III) containing more than 2 x m 3 of Classes 2L, 2 or Class 3 flammability refrigerant shall be secured with a fenced enclosure or barrier to prevent unauthorized access to the equipment. Example propane, 2 x m 3 = 9.8 kg

28 Part 4: Operation, maintenance, repair and recovery

29 Scope Subclauses of this part of ISO 5149 are not applicable to unitary systems having a power cord, being factory sealed, and in conformance with IEC series. Applicable to site-assembled systems, but also appears to include split systems which are not factory sealed.

30 Documentation Clause The party concerned shall keep an updated logbook of the refrigerating system.

31 Other useful information Annex A Draining oil Annex B Recycled refrigerant Annex C Handling & storing refrigerants Annex D In-service inspection Annex E Corrosion inspection

32 Thank you! Questions?