For Private Offices • Open-Plan Offices • Offuce Corridors

• The Value of Lighting Quality
• Lighting Fixture Specifications
• Lighting Controls for Offices
• Private Office Layouts
• Open-plan Office Layouts
• Office Corridor Layouts

 

This guide gives you the knowhow to provide "energy effective" lighting for offices lighting systems that save energy while creating a comfortable and productive work environment. Energy conserving lighting products are common,but not all products are appropriate for all applications.

Lighting fixtures and controls must be carefully selected and located to provide the proper balance of energy savings and lighting quality.

Providing an adequate quantity of light (measured in footcandles) is not enough.
Lighting quality means comfort, good color, uniformity and balanced brightness relationships factors that contribute to long term work performance.

Shadows, glare, flicker or chaotic patterns of light or fixtures are distracting to employees and should be avoided.

 

Penny Wise And Pound Foolish   Employees' salaries are the costliest part of running a business. If poorly designed lighting distracts the average occupant for only 1% of the time, this is equivalent to a $5 per square foot annual loss.   Good quality lighting is an essential part of occupant comfort and satisfaction, providing productivity benefits in the short run and potential employee retention in the long run.   The design strategies and Chip On Board LEDs Light Technologies herein can provide office occupants with a safe, comfortable and cost-effective lighting system, and reduce energy and maintenance costs.

In open-plan offices, lighting the walls and ceiling provides a major improvement in lighting quality.

ACHIEVING BETTER & BETTER YET RESULTS

 

This knowhow guide shows you basic lighting solutions that will deliver Better quality and more energy-efficient lighting systems for offices than traditional approaches. The Better Yet solutions identify further improvements and efficiencies.

If lighting quality isn't achieved in the initial design, occupants will try their own remedies, with serious consequences for energy consumption.

 

Office Quality Issues : Glare

 

Glare occurs when bright light sources interfere with the viewing of objects or surfaces that are less bright.
The contrast between very bright and less bright may be uncomfortable or disabling, both of which are undesirable in an office environment.
Fixtures located to the front or side of the employee cause direct glare. Overhead glare is caused by excessive brightness directly above. Reflected glare occurs on computer screens from images of fixtures located behind the employee.
Reflected glare can also occur on glossy paper from lights directly in front. Most glare can be controlled either by increasing the brightness of the surroundings or decreasing the brightness of the sources, or both.

 

Some contrast-reducing suggestions:

 

• Increase room surface brightness by illuminating walls and ceilings, and using lighter colored materials.
• Increase the brightness around the glare source by using semi-specular or white louvers, or by indirectly illuminating the ceiling. (See fixture type 'E').
• Shield the lamps from view with baffles, louvers, lenses or overlays.
• Reduce the brightness of the lamps by using more lamps of lower brightness. Use more fixtures if necessary.

 

 

Preventing Overhead Glare

 

While many lighting fixtures are designed to shield the view of lamps from "normal" viewing angles ( eyes straight ahead ), fixtures with exposed lamps (downlights, fluorescent parabolic troffers) can still produce glare which impedes office work.

 

To Avoid Overhead Glare

 

• No more than three T-8 lamps in a 2 x 4 fixture.
• No specular ( shiny ) reflectors visible from any angles.
• No specular louvers or baffles ( semi-specular or white only ).
• No T-5 lamps visible from any angle.

Lighting Walls And Ceilings

 

To provide a productive working environment, lighting must be designed for long term comfort.
Lighting the wall and ceiling reduces contrast, shadows, glare and distractions ¡ª all of which are directly related to a worker's performance.
While the desktop and the worker's task should be the brightest surface in the room, the walls, ceiling and partitions should be about 1/3 as bright.
Rooms with darker colored walls or partitions, which absorb light, may never achieve a good balance of brightness.

 

Reflectances

 

Light is absorbed every time it is reflected off a room surface.
Light colors reflect more light than dark colors.
Select ceilings that are white and reflect at least 80% of the light.
Select light colored vertical room surfaces in work areas ( walls, panels, overhead bins ) which reflect 65% or more.
All major surfaces should be matte, not shiny, to improve uniformity and avoid reflected glare.

A small increase in room reflectances produces a big improvement in efficiency.
The lighter room provides 55% more light on the work surface for the same energy or uses 70% less energy to provide equivalent brightness.
The lighter room also provides better brightness ratios, comfort and daylight distribution.