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Generally...

Be aware of situations where you may have problems.

Closed rooms with fluorescent lighting would be an example.

If you know you'll be sleepy in a particular environment, have some coffee.

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Flicker, Drowsiness, Migraines, Optical Sensitivity

This ranges from excess light to monitor flicker

Fluorescent lighting commonly causes problems, generally associated with a perception of flicker. These include drowsiness, headaches, migraines, and difficulty in concentration. This is probably related to:

1.   Flicker at line current frequency, following a step function.

The flicker is at 100 or 120 Hz (half-cycles for 50 or 60 Hz current), which theoretically cannot be perceived. What we see as flicker is an effect of the pulses as sensed by the retina.

The step function is the result of the light "turning on" near the peak of the half-cycle. This may be a reason that fluorescent lighting causes more optical difficulties than other forms of direct conversion lighting.

2.   Low frequency flicker caused by worn out equipment.

3.   Poor light quality in terms of narrow spectrum light output.

The cause is a matter of speculation; however it is known that some people who have problems with fluorescent lights seem to be less affected by compact fluorescent (CF) lights and other fluorescent lights which use electronic ballasts.

Unfortunately, CF and other electronically ballasted lights do cause problems for some people. Therefore, the "flicker" hypothesis does not explain all of the problems with fluorescent lighting.

Fluorescent lights have less adverse effects when mixed with daylight or ordinary incandescent light.

Some of the modern fluorescent lights with built-in electronic ballasts are supposedly better in this regard. The light quality is still poor, but the line current flicker is eliminated.

If you work in a fluorescent-lit room, get a different light.

Halogen floor lamps can be purchased for $35. Some can accept up to 300 watt bulbs (500 watts for the rheostat type, but 500 watts is no longer approved for fire safety reasons).

At a workplace, it may be advantageous to say that the ballasts in the fluorescent lights are "worn out" or otherwise defective. The repair is available, but replacing of all these lamps is (perhaps) not economical. (Hence the floor lamp is saving the company a lot of money.)

(Actually some businesses have found that replacing the ballasts is economical because of costs savings in power used and service life of the tubes and long term replacement costs. Still the idea is to explain that the personal lamp is a way to save the company money -- which is true if one considers replacement of equipment in a single office.)

It turns out that the halogen lights are actually energy efficient. Consider a typical office workspace, with 2 fluorescent ceiling fixtures. (That's typically 4 tubes/fixture) 8 tubes at 40 w / tube, or 320 watts, plus about 30 or 60 watts for 4 magnetic ballasts.

Compact Fluorescent (CF) Lights

"Compact Fluorescent" lights are the small fluorescent lights designed to replace an ordinary incandescent bulb. They use an electronic ballast that operates at 25 kHz to 40 kHz.

CF lamps are useful for areas that need continuous lighting, but light where quality is unimportant, e.g., a common hallway. They may not be economical for lights that are switched on for short periods of time.

CF lights do not resolve the problems experienced by many people with fluorescent lights, and there are definitely people who cannot tolerate the lighting of any fluorescent light source, including electronically ballasted fluorescent lights.

Use separate lights for security lighting and the like.

A 15 watt CF light on a timer is a lot cheaper to operate than an ordinary room light. When you're spending time in the room with the regular light on, the fluorescent light on the timer won't be much of an irritant. Also, with the timer, you can manually switch off the fluorescent light, for a single timer cycle, at will.

A CF fluorescent light in a room which also has incandescent or natural light will have almost no adverse effect (provided that most of the illumination comes from the incandescent lighting).

Technical information related to CF lights and lighting quality here.

Electronic ballasts are available for standard fluorescent lamps, which is a good alternative if you have fluorescent lamps already installed in a place you own.

These are apparently 20% more efficient than conventional magnetic ballasts. Electronic ballasts still cost more than magnetic ballasts (approx. 50% more at the end of 2008) but are far less costly to use because of longer lamp and ballast life in addition to the reduced power consumption. If these things drop in cost at half the rate suggested by Moore's law, magnetic ballasts will be a historical artifact by 2010.

It may well be that conversion to electronic ballasts is already more economical than leaving the old ballasts in place.

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Workplace Accommodation

Avoiding fluorescent lights in the workplace presents its own set of challenges. For one thing, there's the issue of how to bring up the subject.

Bringing Up the Issue

The limitations here are

1. Doing so within the constraints of your disclosure of autism;
2. How much extra accommodation you wish to ask of your employer; and
3. The effect on others in the workspace.

1. "Within the constraints of disclosure"

Fortunately, sensitivity to fluorescents is widespread. Approaches can include:

- "Fluorescent lights bother me." (Note "bother me" is less medical sounding than "sensitive to". Being "sensitive to" crappy perfumes is seen as more acceptable than "sensitive to" something more related to neurology.)
- "I am sensitive to fluorescent lights." This is appropriate in some work circumstances, especially where one has exclusive use of the office or workplace. It has the advantage of implying a need for personal lighting for purposes of workplace accommodation. Again, sensitivity to fluorescent lights is fairly common.
- "I need the non-fluorescent lighting to avoid (migraines, vascular headaches, headaches, fatigue)."

This is generally regarded as a non-autistic issue:

search results for <fluorescent headache> 367,000 hits
search results for <fluorescent headache -autism> 310,000 hits ("autism" decluded)
search results for <fluorescent headache autism> 59,100 hits ("autism" included)

2. "Extra Accommodation"

Normally "accommodation" only becomes an issue if the light is objected to. (No, don't bring in a gas light!) Most employers will permit an exception to the rule if the light is a form of workplace accommodation.

Halogen luminaires are objected to in some college dormatories. Most allow non-halogen lights, but if not, it may be helpful to obtain a medical note.

It's a good idea to place these things on power strips. That allows you to positively switch the light off at night, to avoid fire safety concerns. (You're more likely to find the power strip objected to in some large offices, in which case, you simply remove it, and possibly request an approved power strip.)

In many cases, the personal light is viewed as a type of decoration. A number of people use various types of lights in their offices. In my office, people enjoy the lighting from my halogen light. They just consider it a personal improvement, a little like fancy wheels on a car. They know I don't like fluorescent light, but there are no further issues.

A good reason to request that the lights be left off -- they're effectively broken and cannot be economically repaired. "The ballasts are 'worn out' or otherwise defective. Replacing all of these lamps would be uneconomical." The idea is that your personal light is a way of avoiding complaining.

3. Others in the Workplace

This applies of course to shared workplaces. Fortunately, most of the effects of fluorescent lighting can be mitigated by augmenting the fluorescent lights with incandescent lights. At one office I enjoyed for about 3 months (in an historic building), I used a pantograph-type desk lamp adapted to accept a 100 W halogen bulb. The overhead fluorescent lights were on when others were working there.

It may be possible to talk your employer into replacing the ballasts with electronic ballasts, but except where a safety issue is involved (see below), the employer may object to the extra cost. (On the other hand, if the employer is for some reason already viewing the fluorescent lights as a problem, it may be worth suggesting the replacement of the ballasts as a "cheap alternative".)

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Safety Issues

A separate issue is the safety of fluorescent lights in workplaces which include machinery. The flicker can create a strobe effect which can make it possible for a worker to accidentally get caught in moving parts. Since this is most likely to occur when the worker is distracted, fluorescent lights are dangerous near moving machinery.

This safety problem is readily solved by the replacement of old style ballasts with electronic ballasts. Advantages include longer life of the fluorescent tubes, as well as avoiding workplace accidents. Some employers appreciate having this pointed out, although others will regard safety suggestions with suspicion. (Most large employers encourage such safety suggestions, and a suggestion combining "safety" with "cost savings" is regarded favourably.)

Some machinery includes warnings concerning operation with fluorescent lighting, which means that the electronic ballasts improve workplace efficiency.

Another advantage to replacing ballasts is that the electronically ballasted fluorescent lights are less likely to interfere with optical timing equipment and similar devices.

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Other Optical Issues

This ranges from excess light to monitor flicker

Wear sunglasses or Irlen lenses

Irlen lenses are colour-matched to the individual's optical sensitivity as determined by testing the individual.

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"For months I've been wanting to ask the question, 'Where are you, Al Gore?' You can only polish that Oscar for so long. And the Nobel was decided by Scandinavians! I don't blame you for not wanting to enter the viper pit again after you already won. But getting us to change out our incandescent light bulbs for some irritating fluorescent ones isn't going to save the world. All it's going to do is make us more agitated and jumpy and feeling like once we get home we haven't really left the office. - Michael Moore, 2-Jan-08, commenting on the US Presidential candidates.

First posted 11-Jan-03, and 5-Aug-07 as a separate page. Last revised 21 Sep 09.

Questions - see FAQs.