Match Light Levels to Needs

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Affordability

Lamps and switches that give workers control of their light are fairly inexpensive and with substantial energy savings and increased employee comfort, you can quickly recoup the costs.

Cost savings

One place to save on lighting energy use can be by reducing the number of lights on for night cleaning. Having night cleaning staff use lights efficiently, lighting only the area they are in, can lead to great energy savings for no cost. Write energy efficiency standards into cleaning contracts.

Environmental considerations

Task lamps relieve inefficient overhead lights of their massive duties, notably reducing energy use and overlighting. It is easier to turn off localised lighting when it isn’t needed than to shut off lighting from a general overhead source.

What you need to know

• Assess your current lighting to determine areas that are under or over lit, lights that are controlled by the same switch, staff comfort levels, ways to maximize daylight and the effectiveness and efficiency of your current lighting layout. Knowing what already works and developing a lighting plan can save time and labour costs in the long run.
• Giving workers control over their lighting has been found to result in energy savings and increased workplace satisfaction. Task specific or directed lighting makes for a more comfortable and aesthetic workspace. An over lit office can be uncomfortable and increase agitation and distraction. In offices, task lamps are a healthy choice, as they help reduce eyestrain.
• Workers who use computer display terminals typically prefer relatively low lighting levels to minimize glare and reflections on their display screens. On the other hand, workers who read, write and draw on paper typically prefer higher lighting levels so they can see small letters and fine details. Older workers, and others with weak vision, also need higher lighting levels. The ability to adjust lighting levels is particularly important for workers seated near windows, who must adapt to varying levels of sunlight during the day and workers who require adjusted lighting levels for the different daily tasks that they perform.
• In recent years, technological advances have produced personal dimming systems that make it feasible for individual workers to control lighting levels in their personal workspaces. These systems offer the potential to save energy through their dimming capabilities and to reduce electrical demand during peak hours. However, they will rarely pay for themselves on that basis alone. Most companies justify them based on the dimming systems' positive effect on employee morale and performance.
• Consider delamping, removing unneeded light bulbs or fixtures, in areas with excess lighting levels such as near windows, in hallways and in areas with no furniture. Ensure you maintain safe and comfortable light levels.
• When you need to replace your fluorescent tubes, change T12 tubes for more efficient T5s.
• Buy lights with an appropriate colour temperature for the task and location.
• Aluminum or silver reflectors inserted into overhead light fixtures can reradiate light, requiring half the number of lamps to maintain an equal level of brightness.The reduced number of lamps can also lower the heat produced by lighting.
• Full lighting may not be necessary before and after public hours.
• Provide appropriate light for employees to do jobs such as cleaning or restocking shelves.
• Light only occupied areas of your building during cleaning. Ask janitorial services to light only one area of the building at a time while cleaning, rather than having the entire building unnecessarily lit. Take advantage of partial switching (such as turning on only one lamp of a three lamp fixture) to further reduce energy use during building cleaning.
• Have janitorial staff clean lamps and reflectors, or assign this as a regular duty for other staff. Dirt and dust accumulation can reduce light output by 30%. As well, inspect your lighting systems for surface dents, scratches and burns that can lead to rust formation. Rust can affect the reflectance on the inside surfaces and decrease lamp life.

Taking it further

• Write energy efficiency guidelines into contracts with cleaning staff.
• Install lighting controls to turn lights on only when needed and to provide the required amount of light.
• Contract a professional lighting assessor to strategize how to reduce unneeded lighting and focus light where and when it is required.
• Install dimming controls where appropriate so lights adjust to lower levels when rooms are not in use, or when tasks vary.
• Dimmer controls can be local, centralized, or even wireless. Ensure your fluorescent and compact fluorescent bulbs are compatible with dimmers.
• Occupancy sensors turn lights off automatically when an area is unoccupied, saving 15–80% of lighting energy. These are most effective in areas where there are periods of vacancy, like lunchrooms, washrooms, or storage space. Sensors will also come on when there is someone present, making a parking area or an entrance more comfortable and secure.

FAQ

Will lower lighting levels make the employees drowsy or cause eyestrain?
The idea is not to make the workplace dimly lit, but to use appropriate localized light levels. Over-lighting can actually make a workplace uncomfortable and distracting. In addition, giving workers control over their lighting has been demonstrated to increase productivity and workplace satisfaction.

I've heard of depression affecting office employees because of poor lighting. Are full lighting spectrum lamps healthier for the office?
Seasonal Affective Disorder (SAD) is a type of clinical depression related to morning light deprivation, usually in the late fall and winter days. It is an acute depression, which can be a serious, life threatening condition and thus requires medical advice. Treatment of SAD consists of exposure to high light levels for 30 minutes each day, preferably before 10:00 a.m.

Full lighting spectrum lamps have not been proven to be any more effective in treating SAD than standard sources. One can argue that any light source that embodies all the colours of the rainbow, thus covering the full visible spectrum, is a "full spectrum" source. Even high-pressure sodium (HPS) lights meet this definition. A more conventional definition refers to the Colour Rendering Index (CRI) of the light source. Generally, if a source has a CRI greater than 92, it is classified as a "full spectrum" source.

What is the best energy-efficient lighting that will increase employee productivity?
In order for employees to be productive, they have to be comfortable in their work environment. Proper lighting plays a huge role in the visual comfort of employees, customers and other occupants. Systems that provide proper light distribution with reduced glare and dimmable capabilities gives users ultimate customization and control. Newer technologies such as T8 lamps with electronic ballasts increase the lighting output, eliminate flickers, offer an excellent colour rendition (have a high Colour Rendering Index) and save energy. Also, direct/indirect linear suspended fixtures eliminate glare and increase the visual comfort of the occupants. Dimmable intelligent lighting systems allow the user to control light levels and save energy.

For more specific information on proper lighting alternatives for your building, contact us about the Power Smart Alliance.