9
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
