In 2011, the European lighting norm EN 12464-1 was updated. This update
will lead to changes in how indoor workplaces are designed. Glamox Luxo
will focus on these changes by explaining what they mean for indoor
lighting installations.
The fundamental philosophy behind the new norm requirements is a wish
for better ergonomics on peoples’ work places through increased
illuminance on wall and ceiling and through improved conditions for
visual communication.
More light on walls and ceilings will
increase well-being and improve navigation in a work environment. Also,
newer studies have shown that increased light levels in the room can
improve concentration and recognition.
Visual communication is
interaction between people based on mimicry and body language. This
assumes more vertical light, i.e. light on a vertical surface. One
measure for vertical light is called cylindrical illuminance.
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The cylindrical illuminance Ez is the average of all vertical light on an imaginary
cylinder. The modelling effect is the ratio between cylindrical and
horizontal illuminance (Eh).
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As the figure shows, this is the average of all light that hits vertical surfaces on your head. But a lot of light in your face is not enough. To read facial
expression requires that the light does not wash out all details, but
that it creates shadows and contrasts. This can be measured with what we
call the modelling effect, which is the ratio between light from all
sides (cylindrical illuminance) and light that hits the top of your head
(horizontal illuminance). To have an optimal modelling effect, this
ratio should be between 0,3 and 0,6 in the new norm. The recommended
values for cylindrical illuminance and modelling effect only applies in
so called activity planes that are positioned in the room based on where
the user is or where the visual communication is intended to take
place. The figure shows the layout of activity planes in an office
landscape.
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Activity planes in an office landscape; One at 1,2 metres where people sit and one at 1,6 metres where they stand and walk.
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The
complexity in the new lighting scheme increases somewhat because the
norm separates between recommendations and requirements. The required
values are lower than the recommended. In environments with increased
need for visual communication, like e.g. offices, hospitals and
classrooms, the recommended values should be followed. What the industry
practice will be on this matter remains to be seen because the norm is
still new. Glamox Luxo always recommends the best ergonomic solution
because this will increase the workers’ well-being and productivity.
To
comply with the new norm will in most cases lead to a significant
improvement of the work environment but it may also lead to increased
lamp wattage, more luminaires and a different luminaire lay-out. Hence
it is important that the luminaire manufacturer, end user, electro
consultant and builder enter a dialogue to understand the consequences
of the new requirements. Glamox Luxo has already evaluated how the new
norm affects our concepts for school, office and health care. In many
cases, the lamp wattage must be increased or more luminaires are needed.
Energy savings should not be prioritised at the expense of light
quality, we think. Rather, focus should be on turning the light off
when nobody is present. Glamox Luxo recommends lighting solutions that
are individual, energy saving and flexible for all users and customers.