ISO DIS 20854
Freight Container - Thermal containers - Safety standard for refrigerating systems using flammable refrigerants - Requirements for design and operation
|Publication Date:||28 August 2018|
|ICS Code (General purpose containers):||55.180.10|
This standard is restricted to refrigerating systems integrated with or mounted on ISO thermal containers according to ISO 1496-2. It provides minimum requirements for reducing the risk associated with the use of flammable refrigeration systems.
Industry best practice and standards for the safe operation of flammable refrigerants in refrigerating systems used in thermal freight containers operated on board ships, in terminals, on road, on rail and on land is described.
The scope is limited to container refrigeration systems operated in conjunction with the carriage of refrigerated cargo or when used as a non-operating reefer (NOR) or when empty for positioning - while in intermodal transit. Static land-based continuous operations are excluded.
Methodologies for reducing the risk through design and operation of the refrigerating system during its lifetime, up to and including disposal, is covered in this standard.
The standard addresses the use of flammable refrigerants with classifications defined in ISO 817, defined as 2L, 2 and 3, except R717 (Ammonia). The basic principles to address risk are identical for all flammable refrigerants. However, the severity and consequences of accidents are related to the use of specific refrigerants and will thus affect the final design.
The standard requires a risk assessment, which must take into account the differing nature of the refrigerants as well as including combined operation or transport of all types of MRU using non flammable and flammable refrigerants. In particular, the risk assessment must consider the possible presence of a source of ignition (SOI) in adjacent containers.
In summary, the scope of this standard is to provide:
- Specific requirements for the risk assessment and subsequent design of the refrigeration system;
- General guidelines for the operation, accident prevention, requirements for operating instructions, service, repair and maintenance.