Light Pollution:

The Neglected


By John Batinsey
Member, Eatontown, New Jersey, Environmental Commission

A version of this article appeared with the same title in the
Winter 1994 issue of ANJEC Report.

Do you sometimes find yourself squinting at night just to see the roadway? Do you ever wonder why that is? Surely all the glare and obtrusive light causing this loss of visibility must be necessary-part of civilization.

After researching the causes of light pollution, the Eatontown Environmental Commission realized that we can have effective outdoor lighting without these problems. As a result, Eatontown adopted a comprehensive outdoor lighting ordinance whose goals are to reduce unnecessary glare, thereby improving night-time visibility for safety and security. The ordinance will also help reduce unnecessary sky glow. Most of these improvements will even save energy, as well as reduce cost.


Much of the outdoor lighting that we see at night wastes energy in the following different ways: by excessive illumination, by unshielded or misaligned light fixtures, and by inefficient lamp sources.


The Illuminating Engineering Society of North America (IES) publishes recommendations for the lighting industry that include illuminance levels for outdoor lighting. We think these recommendations are safe and adequate and generally need not be exceeded. Increasing these levels is usually a waste of energy, since our eyes quickly adjust and the brightness often appears to be about the same.

Another waste of energy is when parking lots are brightly saturated with light after closing hours. The IES recommends reducing lighting levels "to maintain security when there is a low level of nighttime activity". This can easily be accomplished by leaving lights on near building entrances or other crucial places and to shut off most or all the rest.


Shielded light fixtures are generally referred to as "cutoff". When non-cutoff fixtures are used, glare is usually present within a driver's field of view. Luminance is the light we see reflected off the roadway surface or object being observed. When glare is visible, the IES states "stray light within the eye produces a veiling luminance...thereby impairing the ability of the driver to perform visual tasks". Utilizing full cutoff light fixtures significantly reduces glare and the "veiling luminance" effect, thus improving visibility.

Floodlight type of light fixtures, when misaligned or without appropriate visors, can contribute heavily to light pollution. Wall-pack flood lights can't be adjusted for directional control and are a poor choice for almost any outdoor lighting use. When improperly installed on buildings or poles, floodlights may even send more light upward and sideways than within the intended target areas.

The criterion for designing outdoor lighting has mainly been illuminance (the light that reaches the surface of the roadway or parking lot). However, the IES states "The human eye cannot see the light that strikes the pavement. It can only react to the pattern of light that is reflected in its direction". When glare is present, the veiling luminance effect "kicks in", blocking our ability to see all of this light. We do, in a sense, waste energy to produce light that we can't see because of glare. Even discomfort glare, a lesser kind of glare, should be avoided when possible. The IES says "discomfort glare may cause fatigue which may result in driver error".


Use of the best lamp for the lighting task is crucial for maximizing energy efficiency. For example, if metal halide lamps were chosen over high pressure sodium (HPS) lamps to illuminate a parking lot it could cost 30-50 percent more in energy use than is necessary. If mercury vapor lamps were selected over HPS, the additional energy required could be 150 percent greater.


Well designed outdoor lighting systems utilizing shielded luminaires should not cost more than poorly designed systems. In fact, reducing light pollution could even save money. The International Dark Sky Association (IDA), an organization that has been leading the anti-light pollution movement, estimates that over a billion dollars is wasted each year in unnecessary energy use.

The answer is not more light but the right kind of light. Cities and towns have never been more brightly lit, yet there is more crime than ever before. To a great extent, the attitude toward outdoor lighting today is like that of the auto industry during the gas-guzzling days of the sixties and seventies. If some light is good, then more must be better.

We're being blitzed with advertising for home security lighting by discount and home improvement retailers. Some of these light fixtures are energy efficient, but most are not. Some have directional control capability, but most do not. Glaring bright security light from dusk to dawn create a blinding illusion of home protection, but intruders can often hide in the harsh shadows from this glare. Being safe and feeling safe are not the same.


Electric utility companies are promoting dusk-to-dawn leased security lighting programs that involve the installation of floodlights on utility company poles within the public right-of-way. This program raises the following problems:

1. Severe glare and spill light is often seen from adjacent roadways and private property. We feel this glare can sometimes be dangerous, especially with foggy windshields during inclement weather conditions.

2. Because of the location of utility company poles, proper distribution of the light is not always attainable.

3. These floodlights sometimes supplement existing parking lot lighting, which in total, can exceed the IES illuminance recommendations.


Jersey Central Power & Light has agreed to utilize only full cutoff cobra head light fixtures on all new street lights installed in Eatontown. This decision places JCP&L in good company with other electric utilities in cities like Seattle, Boulder, and Charlotte, North Carolina, to name a few that have already converted to shielded street lights. With regard to leased floodlights in Eatontown, JCP&L said they will meet the requirements of the new outdoor lighting ordinance and correct any installation that is not in compliance. We're quite pleased with this decision and hope that it is extended to other municipalities as well.


The New Jersey Turnpike Authority has been utilizing full cutoff lighting for improved visibility, but the New Jersey Department of Transportation has not. Glare reduction has not been a part of the DOT's roadway lighting policy.

The New Jersey Department of Environmental Protection has a program to conserve energy used for interior lighting but not exterior lighting.


The New Jersey Light Pollution Study Commission will, hopefully, investigate all of these concerns during 1995. This 13-member commission will have diverse representation. Four will be from the major departments of the State and the rest from the private sector. Of these, three will include the New Jersey electric utility companies and the remainder will represent the environment, the IES, the lighting industry, law enforcement, business community and astronomy.

We hope the commission will, as part of its agenda, seriously consider the type of measures included in the Eatontown Outdoor Lighting Ordinance.

Reducing light pollution in New Jersey should not be difficult. This has been clearly demonstrated in other areas. The enactment of light pollution regulations began in Arizona and California, to reduce sky glow that was impeding astronomical research in those states. It soon became evident that reducing sky glow yielded many other benefits besides, such as energy conservation and improved roadway visibility. The IDA deserves most of the credit for these accomplishments.

Light pollution as an environmental problem has been mostly overlooked, perhaps because outdoor lighting represents a small part of total energy use. We all know of the multitude of problems threatening our environment. Most are difficult and costly to rectify, so let's "do" an easy one for a change. Let's use light and not waste it.

Updated 8-8-96