Flashcards in 10.2 Lighting Deck (10):
Interior lighting can be categorised as
general, localised or local
Provides uniform illumination over the whole working area
and does not limit positioning of the work.
Provides different levels of illumination in different parts of
the same working area. It matches the level of illumination
to the needs of specific tasks.
Usually a combination of background lighting and a
luminaire close to the actual work area. Used when:
a high level of illumination is needed in a small area
flexible directional lighting is required for different tasks
at a workstation
general lighting is unnecessary or impossible to install
because of the layout of the work area
Lighting hazards may originate from: 4
Incorrect lighting design.
Improper lighting installation, maintenance, replacement and disposal.
Improper selection of emergency lighting.
Hazards from lighting effects
Field measurements of illuminance may be required for the following reasons: 3
To establish whether a new installation has achieved the design specification.
To establish whether an installation meets a desired criterion.
For trouble-shooting in identifying the causes of complaints about the lighting.
The candela is the SI (international) unit of luminous intensity. It is equal to one
lumen per steradian.
Historically one candela was the amount of visible light emitted by one standard
candle in a given direction.
The lumen is the SI unit of luminous flux, used in describing a quantity of light
emitted by a source or received by a surface.
The lumen was created as the measure of total luminous power (i.e. visible light
power) as defined by a set of ideal human eyes.
One lumen is defined as one candela-steradian (cd sr), or the amount of light power
needed to send 1 candela of light in all directions.