ISO 13043:2011

INTERNATIONAL ISO
STANDARD 13043
First edition
2011-04-15
Road vehicles — Refrigerant systems
used in mobile air conditioning systems
(MAC) — Safety requirements
Véhicules routiers — Systèmes réfrigérants utilisés dans les systèmes
d’air conditionné embarqués (MAC) — Exigences de sécurité
Reference number
©
ISO 2011
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2011 – All rights reserved

Contents Page
Foreword .iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Safety targets . 7
4.1 General . 7
4.2 Risk assessment . 8
4.3 Relevant inputs and scenarios for the risk assessment . 9
5 System level requirements . 11
5.1 Refrigerant system . 11
5.2 Pressure and temperature ranges .12
5.3 System layout .12
5.4 Pressure and temperature limitation strategies .12
6 Component level requirements .12
6.1 General requirements .12
6.2 Piping and connecting technology .13
6.3 Compressor .14
6.4 Evaporator .15
6.5 Condenser/gas cooler .15
6.6 Receiver and accumulator .15
6.7 Service ports .15
6.8 Control devices .15
7 Design requirements for service and manufacturing .15
Annex A (normative) Relevant input values for the risk assessment of refrigerants R‑134a, R‑1234yf and
R‑744 .16
Annex B (normative) Pressure and temperature reference data .19
Bibliography .21
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International
Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 13043 was prepared by Technical Committee ISO/TC 22, Road vehicles.
iv © ISO 2011 – All rights reserved

Introduction
For many years, R-134a has been the refrigerant of choice for refrigerant systems for mobile air conditioning
(MAC) due to its thermodynamic properties, worldwide availability and relative low cost. However, its contribution
to global warming is now considered to be unacceptable. Additionally, it has been documented that the rate of
growth in atmospheric loading of R-134a is of growing concern.
In 2006, the EU formulated legislation 2006/40/EC to ban the use of greenhouse gases having a global warming
potential (GWP) of more than 150. Since R-134a has a GWP >1300, the European Directive has banned the
use of R-134a for new model types since 1 January 2011 and for all new vehicles starting on 1 January 2017.
The automotive industry has responded by identifying two materials that would comply with the European
Union GWP requirement and offer acceptable refrigeration performance. These products are R-744 (carbon
dioxide, GWP of 1) and R-1234yf (2,3,3,3-Tetrafluoroprop-1-ene, GWP of 4).
In certain concentrations, both products could lead to a safety hazard to the vehicle occupants and to technicians
who service the vehicle. This International Standard aims to identify refrigerant system safety requirements, to
be met through robust engineering solutions and applied to the vehicle design, to maintain a comparable level
of safety as that of MAC systems using R-134a.
INTERNATIONAL STANDARD ISO 13043:2011(E)
Road vehicles — Refrigerant systems used in mobile air
conditioning systems (MAC) — Safety requirements
1 Scope
This International Standard is restricted to refrigerant systems providing cooling or heating of passenger
compartment, battery, etc., in passenger motor vehicles. It provides minimum design requirements for
refrigerant containment and safety requirements of these systems.
This International Standard addresses the use of only R-134a, R-1234yf and R-744 refrigerants in vehicle
original equipment manufacturer (OEM) and aftermarket (non-OEM) supplied components and systems.
The relevant risks associated with these refrigerant systems are:
— projection of fragments or fluid due to high pressure systems;
— inhalation of toxic substances, including potential decomposition products;
— flame propagation.
Consequently, this International Standard will address the component and system design requirements related
to any of these hazards where the refrigerant system is involved.
Any scenario involving other components from the heating, ventilation and air conditioning (HVAC) system
(heater, blower, air mixing and distribution) or any other component of the vehicle not related to the refrigerant
system will not be covered in this International Standard.
The purpose of this International Standard is to ensure that end-users or service technicians are not exposed
to hazards during normal usage, maintenance and repair, and end-of-life disposal of the car. Therefore,
manufacturing, storage and transportation of the refrigerant, as well as refrigerant distribution and filling
machines in the assembly plant will not be covered in this International Standard. For these situations, the
safety of qualified personnel will be addressed by existing standards commonly used among the industry and
relevant regulations.
Entire vehicle lifetime has been considered to address durability issues.
For the R-134a system, this International Standard applies to any new model type launched one year after the
document is published.
For the R-1234yf and R-744 systems, this International Standard applies from first application of these
refrigerants to any vehicle.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced document
(including any amendments) applies.
ANSI/ASHRAE 34-2007, Designation and Safety Classification of Refrigerants
SAE J639, Safety Standards for Motor Vehicle Refrigerant Vapor Compressions Systems
SAE J2064 - R-134a and R-1234yf, Refrigerant Automotive Air-Conditioning Hose and Assemblies
SAE J2670, Stability and Compatibility Criteria for Additives and Flushing Materials Intended for Use in R-134a
and R-1234yf Vehicle Air-Conditioning Systems
SAE J2771 - CO2 (R-744), Refrigerant Removal and Charging Equipment for Mobile Refrigerant Systems
SAE J2772, Measurement of Passenger Compartment Refrigerant Concentrations Uunder Ssystem Rrefrigerant
Lleakage Cconditions
SAE J2788 - HFC-134a (R-134a), Recovery/Recycling Equipment and Recovery/Recycling/Recharging for
Mobile Air-Conditioning Systems
SAE J2842 - R-1234yf and R-744, Design Criteria and Certification for OEM Mobile Air Conditioning Evaporator
and Service Replacements
SAE J2843 - R-1234yf, Recovery/Recycling/Recharging Equipment for Flammable Refrigerants for Mobile Air-
Conditioning Systems
SAE J2845, Technician Training for Safe Service and Containment of Refrigerants Used in Mobile A/C Systems
(R-744, and R-1234yf)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
vehicle
vehicle with a combustion engine and/or electric driving motor, intended for use on the road, with or without
external body components added, having a permissible maximum mass of at least 400 kg and a maximum
design speed equal to or exceeding 50 km/h
NOTE Passenger cars and light commercial vehicles (including light-duty trucks) are covered, with the exception of
heavy trucks and road tractors, minibuses, buses and coaches, agriculture tractors and public work vehicles.
3.1.1
air exchange rate
AER
number of times that the air in the passenger compartment is replaced per hour
3.1.2
air inlet plenum
chamber located in front of the passenger compartment where the air is collected before entering into the
vehicle, usually separating water, snow, and debris from the air prior to its entry into the HVAC module
3.1.3
engine bay
space for a combustion engine and/or an electric driving motor
NOTE 1 In a front-engined vehicle, it is the space between the front grille, the front side fenders, the front of dash (or
firewall) in front of the passenger compartment, closed by the engine bonnet.
NOTE 2 In a rear-engined vehicle, it is the space between rear end and vehicle compartment rear bulkhead, embedded
between engine compartment side panels (fender apron), closed by the hatchback and underneath closed out to various
degrees by an underbonnet shield.
NOTE 3 In a mid-engined vehicle, it is the space between rear end and passenger compartment rear bulkhead,
embedded between engine compartment side panels (fender apron), closed by an engine compartment cover and
underneath closed out to various degrees by an underbonnet shield.
3.1.4
underhood
space in the engine bay where the components of the refrigerant system are located
NOTE 1 In a front-engined vehicle, it contains mechanical or electric compressor, condenser/gas cooler, refrigerant
sensor, accumulator or receiver/drier, at least one expansion device, piping, assemblies, charge and/or service ports, and
an optional internal heat-exchanger.
2 © ISO 2011 – All rights reserved

NOTE 2 In a rear-engined and mid-engined vehicle, it contains mechanical or electric compressor and piping.
3.1.5
vehicle lifetime
design life of the vehicle as specified by the vehicle manufacturer in terms of mileage and years of life
3.1.6
vehicle interior
passenger compartment
vehicle space occupied by the driver and passengers w
...