Page 172 - Offshore Electrical Engineering Manual

Accommodation Lighting 159

ACCOMMODATION LIGHTING

NORMAL LIGHTING
It is not normally possible to provide lighting of the quality and flexibility of a good
hotel, but it is important that the normal lighting is restful and blends with a hope-
fully pleasant decor. Supplementary lighting will be required for reading and writing
areas. Where televisions are viewed, care must be taken to prevent distracting reflec-
tions appearing on the screen. Galleys require a much higher level of lighting with
good colour rendering for safety and hygiene. It is usual in the sleeping cabins, for
each bed to be fitted with a combined lamp and entertainment bedhead unit located
conveniently for operation by the bed occupant, such that he or she may read without
shadow and without head injury when getting up.

ACCOMMODATION EMERGENCY LIGHTING

Suitably hazardous area certified emergency lighting must be provided for the ade-
quate lighting of all rooms and escape routes. Each luminaire should be complete
with a battery, charger and inverter. Schemes where all the emergency lighting is
operated from a single battery are not recommended, for reliability reasons. Each
sleeping cabin must be provided with a hazardous area certified emergency luminaire
located in such a position as to illuminate the exit route sufficiently to overcome
sleep disorientation. Suitable non-industrial designs of certified luminaire, with an
acceptable appearance for use in accommodation areas are now available. With the
exception of the sleeping cabin luminaires, emergency lighting is left operating con-
tinuously. The sleeping cabin units are provided with a mains failure sensing device
and are switched on automatically during mains failure. The same arrangement may
be used in communal TV rooms if required. (If such rooms are earmarked for triage
in emergencies, the luminaires must also be manually switchable.)

PROCESS AREA LIGHTING
To operate satisfactorily and safely in hazardous process areas, luminaires or required
to be mechanically strong in order to resist accidental blows from passing equipment,
tools or scaffolding poles. Plastic cases or lenses must not crack due to vibration
fatigue and the casing should be as free from crevices as possible to prevent the trap-
ping of dirt, oil, etc., and for ease of cleaning. The luminaire must be certified for
use in hazardous areas, and is usually of the Ex ‘e’ increased safety type. Luminaires
should be hazardous area certified to meet ATEX requirements by an ATEX Notified
Body. Some hazardous area certification does not meet the relevant ATEX harmon-
ised standards and may be rejected by the operating oil company. Preferably the lumi-
naire should incorporate a terminal box such that the luminaire enclosure remains
sealed when terminals are accessed, otherwise a separate ‘looping-in’ terminal box
will be required, adjacent to each luminaire. Problems have been experienced with
Ex ‘e’ luminaires, due to water ingress possibly leading to arcing. This is particularly