WITH the increasing use of hydrocarbons, the British Refrigeration Association (BRA) has issued a code of practice for manufacturers and guidance notes for service engineers dealing with these refrigerants.
The Code of Practice for the Design and Manufacture of Refrigerated Cabinets Running on Hydrocarbon Refrigerants sets out to clarify the regulations, standards and practices which apply to the leak simulation testing and subsequent design of systems which use hydrocarbon refrigerants. 

The Code defines standards in the design and manufacture of integral (plug in and hard‐wired) and close coupled remote type cabinets for food display, service and storage (stand alone and multiplexed). It is aimed at cabinets with a charge size greater than 150g. It is also applicable to cabinets with less than 150g, for which other standards also apply.

As it is still unclear whether HC refrigeration systems fall within the ATEX regulations, the Code follows the principles of ATEX with regard to area classification and avoidance of sources of ignition.

The Guidance document for the Service of Hydrocarbon Refrigerant Equipment in a Retail Environment covers leak testing, recovery, evacuation, un-brazing and brazing, charging and component replacement.

The guide does not provide full procedures but outlines the critical points which differ from those for HFC refrigerants. It also recommends that engineers have an F-gas qualification and have attended an HC refrigerant safe handling course within the last three years.

The documents can be downloaded here http://www.feta.co.uk/bra/bra-06.htm