Clearly what we all want and need is security and safety at night, at home and when we are away from home, for ourselves, our families, our homes and property, and for all others. The task is to be safe, not to just feel safe. This means that we need effective and efficient lighting. Visibility is the goal. We want to be able to see, not just have the criminal be able to see. This goal exists for us at home, on the streets, in parking lots, at work, wherever. Good lighting can be a help, poor lighting always compromises safety.
Most crime actually occurs during the day, or inside buildings. However, we want the feeling and the reality of being safe outside at night. That does not mean putting in the brightest light we can find, blinding everyone in the area, creating light trespass and lighting up the sky. What we do need is effective lighting, lighting that puts light where we need it (and nowhere else) and where it will help visibility. That means: no glare, no light trespass, no up light, no harsh shadows, no steep transitions from light to dark, etc. Lighting in itself does not insure safety. Is there more crime in the "well lit" centers of large cities or in smaller towns with much less lighting? A cynic would derive a positive correlation of crime with light: the more light , the more crime. We don't think so. Current and past studies by competent law authorities can be summarized as follows: "The paucity of data preclude any definitive statement regarding the relationship of lighting and crime, but there is a strong indication that lighting decreases the fear of crime." Quality lighting rather than poor lighting is essential for any real security.
This fixture was designed in the old days when energy was cheap, when there were no good lighting fixture designs, and when the adverse effects of bad lighting were not well appreciated. It sells for $29.95 or less, but uses over 200 watts of power. That means it costs about $70 per year to operate in most locations, much more in high electricity cost areas. Much of the light output is wasted, going up or sideways where it does no good at all. It has a great deal of glare, often blinding the homeowner and others. It splatters light everywhere, alienating neighbors. It casts harsh shadows behind trees and buildings, allowing criminals plenty of dark areas to hide in. It is a prime example of bad lighting. But it is in use by millions throughout the country. Why? It's cheap, and bright. We see lots of glare so we think there is lots of light. But it's a most ineffective and inefficient light. It is, in reality, a very poor security light.
Globes are particularly bad. Light is splattered everywhere. Because it wastes so much light, one must put a high wattage lamp inside to get any light on the ground. That means a great deal of glare is produced, so much that often one can't then see the ground! Why are so many of these inefficient fixtures used? Mainly because they look good in the daytime! If one likes that look, then one should put only a very low wattage lamp in (as in the days of gas lighting), preserving the daytime appearance. One can install a separate, quality, lighting system to light the ground. There's no glare or light trespass from this good system, so it doesn't detract from the looks of the globes. One gets the desired attractiveness and also good lighting and safety. It costs more, but there is good lighting.
Poorly shielded "wall packs" or similar fixtures also splatter light everywhere, some getting where needed, but most is wasted. They also have lots of glare. Well shielded wall packs can be excellent light sources, but one must be sure of what one is buying. Some wall packs have good light control, some nearly none.
Poorly designed or installed flood lights don't provide good light either. Flood lights can be good, as they often have good light control. But they must be well designed and installed to take advantage of their pluses. Often they are poorly installed, aimed at what seems a random direction, or worse, right at the street (causing terrible glare for motorists) or at the neighbors yard or bedroom window. We have all seen many examples of such bad lighting at night.
A much better light is a well shielded fixture like this example. The light is directed downward where it is needed.
Three suggestions for a real security light:
- Use a low wattage (18, or 35, or 55 watt) low pressure sodium fixture, as a wall pack or with other mounting with a full cut off or sharp cut off fixture. There is lots of light and little or no glare and no sharp, deep shadows. One is not blinded, one can see. Visibility is the goal. These fixtures offer excellent visibility.
- Use an infra-red sensor spotlight fixture. The spot-lights only come on when the sensor senses movement. Any intruder will be scared off by the sudden turn-on of the spots. You are alerted. Energy use is minimal. What could be better? This type fixture is a great security lighting system: effective, cost effective, quality lighting.
- Use one or more low wattage compact fluorescent lamps in well shielded fixtures. The light level is adequate, and you save a great deal of energy.