Client Background
The client is a communal workspace/residential brand. They required a DSEAR study as the air conditioning system to a server room was using a flammable refrigerant fluid.
Client Problem
The refrigerant R32 is difluoromethane. This can be flammable when mixed with air at more than 14% by volume. The client’s main question was whether there may be any leaks that could accumulate to flammable concentrations.
Client Objectives
Understand if and where potential leaks could generate an explosive atmosphere.
Sigma-HSE found that
The outdoor unit, incidental leaks would be diluted by the outdoor ventilation and ignition sources are excluded in the immediate vicinity of the overpressure vent.
In a worst-case scenario, all the refrigerants could leak into one of the indoor air-conditioned spaces.
A large room space would have enough air to dilute the leak, but in a small room, accumulation to flammable concentrations is possible.
The server room itself was the smallest room that had an indoor unit, and thus presented the greatest risk.
Recommendations
The International Electrotechnical Commission (IEC) has released specific guidance where a given mass of R32 refrigerant corresponds to a given minimum room size (also accounting for imperfect mixing in the room and a safety factor). In this case the server room was smaller than the minimum, so specific leak detection systems were recommended in this room.
Outcome
Customer saved financially as we managed to keep the existing air conditioning system in place without any disruptions to the business.
