21
EN
Intrinsically safe components are the only types that can be worked on 
while live in the presence of a flammable atmosphere. The test apparatus 
shall be at the correct rating.
Replace components only with parts specified by the manufacturer. Other 
parts may result in the ignition of refrigerant in the atmosphere from a leak.
Cabling
Check that cabling will not be subject to wear, corrosion, excessive 
pressure, vibration, sharp edges or any other adverse environmental 
effects. The check shall also take into account the effects of aging or 
continual vibration from sources such as compressors or fans.
Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition be used in the 
searching for or detection of refrigerant leaks. A halide torch (or any other 
detector using a naked flame) shall not be used.
Leak detection methods
The following leak detection methods are deemed acceptable for 
systems containing flammable refrigerants.
Electronic leak detectors shall be used to detect flammable refrigerants, 
but the sensitivity may not be adequate, or may need re-calibration 
(detection equipment shall be calibrated in a refrigerant-free area). Ensure 
that the detector is not a potential source of ignition and is suitable for 
the refrigerant used. 
Leak detection equipment shall be set at a percentage of the LFL of 
the refrigerant and shall be calibrated to the refrigerant employed and 
the appropriate percentage of gas (25% maximum) is confirmed. Leak 
detection fluids are suitable for use with most refrigerants but the use of 
detergents containing chlorine shall be avoided as the chlorine may react 
with the refrigerant and corrode the copper pipe-work.
If a leak is suspected, all naked flames shall be removed/extinguished.
If a leakage of refrigerant is found which requires brazing, all of the 
refrigerant shall be recovered from the system, or isolated (by means of 
shut off valves) in a part of the system remote from the leak. Oxygen free 
nitrogen (OFN) shall then be purged through the system both before and 
during the brazing process.
Removal and evacuation
When breaking into the refrigerant circuit to make repairs or for any other 
purpose conventional procedures shall be used. However, it is important 
that best practice is followed since flammability is a consideration. 
Opening of the refrigeration systems shall not be done by brazing. 
Thefollowing procedure shall be adhered to: