E NE RG Y MAT TER S
FACT SHEET 12:
LIGHTING AUDITS
A lighting audit is like any other form of
audit. It involves:
1. assessment of the current situation –
what lighting systems are in place
2. evaluation of the effectiveness of the
lighting system – is it doing what it
needs to do, or can improvements be
made
3. recommendations
Assess existing conditions
To conduct a lighting audit you will first
need basic lighting information, such as
the number of lights, their location, and
their time in use to help you understand
the current energy use attributed to
lighting in the facility. This information
will help you understand how much you
are currently spending and the potential
savings available from lighting efficiencies.
EXERCISE 1
What information should be gained in
assessing the current lighting situation?
The Australian Standard 1680 series deals
with interior lighting, and includes:
•
1680.0 – safe movement within a
building for general access
•
1680.1 – general recommendations
for work places
•
1680.2 series – lighting
recommendations for specific work
places
•
1680.3 – measurement, calculation
and presentation of photometric data
You will be provided with extracts from
these Standards.
EXERCISE 2
Answer the following questions, using the
AS extracts provided.
(a) What is the recommended
illuminance level for the following
tasks?
Corridor
Training room
Toilet
General laboratory
Microbiology laboratory
Chemical store
(b) A series of illuminance measurements
for a work area are shown below.
250
280
270
300
310
190
210
220
230
220
140
160
130
120
130
Calculate the illuminance uniformity value.
Does it meet the minimum standard?
•
EXERCISE 2 (CONT’D)
(c) Where would you take illuminance
measurements in the following work
spaces?
(i) a corridor 1.5 metre wide
(ii) a storeroom 2 m by 2 m
(iii) a laboratory (10 m x 5 m) as
shown below (the shaded boxes are
lights which are 1.5 m from side and
end walls)
Identify opportunities for
improvement
The following are general questions that
should be asked about the lighting system,
with possible actions to improve the
situation.
Is existing lighting on when it doesn’t need
to be?
•
post reminder stickers to turn off
lights when leaving the area
•
install time switches or occupancy
sensors in areas of brief occupancy
and remote areas (warehouses,
storage areas, etc.).
•
rewire switches so that one switch
does not control all fixtures for
multiple work areas.
•
ensure wall-switch timers function
properly
Energy Matters 12. Lighting Audits
install scheduling systems
Are existing lighting levels higher than
necessary?
•
reduce lighting levels where
appropriate
•
remove unneeded lamps (delamp)
•
eliminate outdoor lighting where
possible and where safety and security
are not compromised.
•
replace burned out lamps with lower
wattage lamps.
Is the lighting less efficient than it could
be?
•
install more efficient (i.e. electronic)
ballasts
•
replace incandescent lamps in offices,
workrooms, hallways, etc. with
compact fluorescent lamps
•
use single incandescent lamp of high
wattage instead of two or more
smaller lamps of combined wattage
•
replace exterior incandescent lights
with more efficiency lights such as
high pressure sodium (HPS) or metal
halide (MH)
•
use light-coloured paint on walls.
•
remove fluorescent lamps controlled
by magnetic ballasts in pairs since
they are operated and wired in pairs
(two fluorescent lamps from a fourlamp fixture); with electronic ballasts,
each lamp is controlled individually
•
replace standard fluorescent lamps
and ballasts with T8 and matching
electronic ballasts (switching from
fluorescent to high-efficiency
fluorescent can save 10 to 30 percent
in energy costs).
•
lower fixtures or use a lamp extender
to increase illumination on a given
area.
•
install reflectors or lenses to spread
out and focus light (specular
reflectors can improve efficiency by
up to 17 percent in fluorescent lights).
•
ensure the layout of room is
conducive to light and that light
obstructions do not exist.
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Is light maintenance carried out regularly?
•
follow a regular a maintenance
schedule
•
establish a regular inspection and
cleaning schedule for lamps and
fixtures
•
establish a group re-lamping schedule
to replace lamps as they burn out,
usually done at 70 percent of rated
lamp life
•
replace yellow or hazy lens shading
with new acrylic lenses that do not
discolour
•
clean room surfaces such as tables,
walls, etc. to remove dirt, increasing
reflectivity
Do the people using the area know what
you are trying to do?
•
ask people working in an area about
the lighting
•
train staff, especially housekeeping
staff, on lighting policies/efficiency.
•
post lighting schedules that display
necessary hours of use for lights so
that staff members know when
turning off lights is appropriate
EXERCISE 3
Undertake an audit of part of your building,
as detailed in Practical Exercise 2.
Can natural light be used more effectively?
•
locate workstations with high
illumination needs adjacent to
windows.
•
turn off lights when daylight is
sufficient
•
install light sensors/dimming
equipment that automatically
compensate for natural light variance
•
clean windows and skylights
•
reschedule housekeeping duties to
operate during the day so additional
after-hours lighting is not needed
Energy Matters 12. Lighting Audits
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