M.DF010-01 Manual 03/09/2021
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If it is absolutely necessary to have an electrical supply to equipment during servicing, then a permanently
operating form of leak detection shall be located at the most critical point to warn of a potentially hazardous
situation.
Particular attention shall be paid to the following to ensure that by working on electrical components, the
casing is not altered in such a way that the level of protection is affected. This shall include damage to
cables, excessive number of connections, terminals not made to original specification, damage to seals,
incorrect fitting of glands, etc.
Ensure that apparatus is mounted securely.
Ensure that seals or sealing materials have not degraded such that they no longer serve the purpose of
preventing the ingress of flammable atmospheres, Replacement parts shall be in accordance with the
manufacturer’s specifications.
NOTE: The use of silicon sealant may inhibit the effectiveness of some types of leak detection equipment.
Intrinsically safe components do not have to be isolated prior to working on them.
10.Repair to intrinsically safe components
Do not apply any permanent inductive or capacitance loads to the circuit without ensuring that this will not
exceed the permissible voltage and current permitted for the equipment in use.
Intrinsically 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 manufacturer. Other parts may result in the ignition of
refrigerant in the atmosphere from a leak.
11.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 consider the effects of aging or continual
vibration from sources such as compressors or fans.
12.Leakage detection for 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.
13.Leak detection methods
The following leak detection methods are acceptable for systems containing flammable refrigerant.
Electronic leak detectors shall be used to detect flammable refrigerants, but the sensitivity may not be
adequate, or may need recalibration (Detection equipment shall be calibrated in a refrigerant-free area.)
Ensure that detector is not a potential source of ignition and is suitable for the refrigerant used.
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 pipework.
If a leak is suspected, all naked flames shall be removed/extinguished.
If a leak of refrigerant is found which requires brazing, all of the refrigerants shall be recovered from the
system. Oxygen free nitrogen (OFN) shall then be purged through the system both before and during the
brazing process.
14.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. The following procedure shall be adhered to:
Remove refrigerant.