During repairs to sealed components, all electrical supplies shall be disconnected from the
equipment being worked upon prior to any removal of sealed covers, etc. 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.
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 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.
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 ageing or continual vibration from sources such as compressors or fans.
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.
Equipment shall be labelled stating that it has been de-commissioned and emptied of
refrigerant. The label shall be dated and signed. Ensure that there are labels on the equipment
stating the equipment contains flammable refrigerant
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