be released to the surrounding space. Prior to
work taking place, the area around the equip-
ment is to be surveyed to make sure that there
are no ammable hazards or ignition risks. “No
Smoking” signs shall be displayed.
VENTILATED AREA
- Ensure that the area is in the open or that it is
adequately ventilated before breaking into the
system or conducting any hot work. A degree of
ventilation shall continue during the period that
the work is carried out. The ventilation should
safely disperse any released refrigerant and
preferably expel it externally into the atmo-
sphere.
CHECKS TO THE REFRIGERATION EQUIPMENT
- Where electrical components are being
changed, they shall be t for the purpose
and to the correct specication. At all times
the manufacturer’s maintenance and service
guidelines shall be followed. If in doubt consult
the manufacturer’s technical department for as-
sistance.The following checks shall be applied
to installations using ammable refrigerants: the
charge size is in accordance with the room size
within which the refrigerant containing parts are
installed; the ventilation machinery and outlets
are operating adequately and are not obstruct-
ed; if an indirect refrigerating circuit is being
used, the secondary circuit shall be checked
for the presence of refrigerant; marking to the
equipment continues to be visible and legible.
Markings and signs that are illegible shall be
corrected; refrigeration pipe or components are
installed in a position where they are unlikely
to be exposed to any substance which may
corrode refrigerant containing components,
unless the components are constructed of
materials which are inherently resistant to being
corroded or are suitably protected against being
so corroded.
CHECKS TO ELECTRICAL DEVICES
- Repair and maintenance to electrical compo-
nents shall include initial safety checks and
component inspection procedures. If a fault
exists that could compromise safety, then no
electrical supply shall be connected to the
circuit until it is satisfactorily dealt with. If the
fault cannot be corrected immediately but it is
necessary to continue operation, an adequate
temporary solution shall be used. This shall be
reported to the owner of the equipment so all
parties are advised.
- Initial safety checks shall include: that capac-
itors are discharged: this shall be done in a
safe manner to avoid possibility of sparking;
that there no live electrical components and
wiring are exposed while charging, recovering
or purging the system; that there is continuity of
earth bonding.
REPAIRS TO SEALED COMPONENTS
- 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 absolute-
ly 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 compo-
nents, 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 specication, damage to seals, incor-
rect tting of glands, etc. Ensure that appara-
tus is mounted securely. Ensure that seals or
sealing materials have not degraded such that
they no longer serve the purpose of prevent-
ing the ingress of ammable atmospheres.
Replacement parts shall be in accordance with
the manufacturer’s specications.
- 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.
REPAIR TO INTRINSICALLY SAFE COMPO-
NENTS
- Do not apply any permanent inductive or ca-
pacitance 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 ammable atmosphere. The
test apparatus shall be at the correct rating.
Replace components only with parts specied
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
