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corresponds to the room area as specified for operation.
2. 2 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.
3 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 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.
4 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.
5 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.
6 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
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