In December 2011 the Singapore Civil Defence Force (SCDF) published a review on the use of hydrocarbon (HC) refrigerants across various applications. Despite acknowledging the environmental benefits of hydrocarbon refrigerants the SCDF has issued recommendations to restrict their use, although hydrocarbons in domestic refrigerators and air-conditioners remain permitted.

Over the years hydrocarbon refrigerants have been gaining greater acceptance as safety issues are overcome and better training becomes available for HVAC&R technicians. Across South East Asia several hydrocarbon conversions have been undertaken, such as in the Maldives, Indonesia and Singapore. A new policy in Singapore, however, will restrict their further use.

Restrictions on the use of hydrocarbons

To manage the safety concerns relating to hydrocarbon refrigerants the Singapore Civil Defence Force (SCDF) has recommended that the use of hydrocarbon refrigerants be regulated as of January 2012. The SCDF has issued the following recommendations:

• Domestic refrigerators and air conditioners: The use of hydrocarbon refrigerants is allowed in SPRING-regulated domestic refrigerators, subject to a charge weight cap of 150g of refrigerant, hermetically sealed within the refrigerator. Their use is also allowed in SPRING-regulated air conditioners;
• Air-conditioning systems: The use of hydrocarbons ought to be disallowed in building air conditioning systems and mobile air conditioning systems. Premises that have converted their air-conditioning systems into using HC refrigerant as a drop-in will be gradually phase-out by the end of 2016;
• Commercial refrigeration systems: The use of hydrocarbons ought to be disallowed in commercial refrigeration systems such as coldrooms in supermarkets and food storage factories;
• Industrial process refrigeration systems: The use of hydrocarbons should be disallowed unless the use of hydrocarbons is inherent to the industrial process, or has satisfied the MOM’s workplace safety regime and SCDF’s fire safety regulatory requirements.

SCDF u-turn despite previous approval given to hydrocarbon chillers

In 2005 the SCDF approved the installation of five air-cooled chillers with a nominal capacity of 700 kW, each containing a charge of approximately 25 kg of a refrigerant blend of R290 and (propane) and R1270 (propylene). The SCDF safety audit conducted ensured that there was adequate ventilation, no exposed electrical or fire source nearby, no smoking signs, proper control of access by the public, and that all electrical components and panels were sealed.

In spite of this approval the December 2011 SCDF recommendations will mean installations such as this will have to be phased out by 2016, an about policy turn by the SCDF.

According to the SCDF circular the new policy will be implemented because hydrocarbon refrigerants are flammable and pose a potential safety hazard. However, if technicians are properly trained, the correct procedures are followed and the right safety devices are in place, hydrocarbon chillers can offer safe and more efficient cooling when compared to fluorinated refrigerants.