prBAS EN 17893:2025

This document specifies requirements for the use of flammable refrigerants class A2L, A2 and A3 as defined in ISO 817 with regard to: - design and construction of the refrigerating system (as far as not specified in EN 378-2); - operation; - in all anticipated operational modes and locations; - including continuous idling during standstill; - service, maintenance and decommissioning; - for the investigation and mitigation of risk for thermally insulated means of transport, including: trucks, trailers, tanks, vans (light commercial vehicles), wagons, containers for land transport, small containers, packaging. This document describes an Operational Mode Risk Assessment (OMRA), which uses methods such as Hazard and Operability Analysis (HAZOP), Failure Mode and Effects and Criticality Analysis (FMECA), or Fault Tree Analysis (FTA) or a combination of these methods. The document specifies requirements: - for the validation of possible safety concepts and protective devices within the OMRA process, including charge release tests, simulation, and function tests of the associated protective equipment; - for tests related to the application; - using methodologies to achieve tolerable risk values. Mobile air conditioning systems in cars are covered in ISO 13043 and refrigerated containers conforming to ISO 20854 are excluded. This document could be used for class "B" refrigerants providing the OMRA is adjusted to account for their specific properties.