A useful addition to perimeter security can be exterior lighting, either switched manually or automatically operated. Lighting does have its limitations - burglaries often take place during daylight hours; if the light is activated, someone has to notice it - and take action. Lighting should be seen as an aid, but on its own it is not sufficient to deter a burglar.
The most common form of lighting is passive infra-red which is activated when someone comes into its field of vision. The light can be set to stay on for a set time and then it will re-set if the cause of its activation is no longer present. A passive infra-red unit can activate single or multiple lights.
Lights can be useful on the approach to a front or rear door or garage, not only lighting up if someone approaches your house, but also when you approach, so that you can see if anyone is lurking in the shadows. It must be remembered though that lights can be activated by certain animals. Also, you do not want the light to be activated every time your neighbours go into their garden or when someone walks past the front of your property. However, the field of activation can be adjusted. You must also make sure that your light does not intrude into your neighbours windows or those of passing vehicles - light pollution can often be at the centre of many disputes.
An alternative is to fit low pressure sodium lights which are operated by a photo-electric cell. This turns the lights on at dusk and off at dawn. It is a much less obtrusive light and, although it is on all night, it can be cheaper to run than spotlights.
These lights can be DIY fitted, but if you are not sure, it is essential that you contact a qualified electrican.
A sensible arrangement of leaving lights switched on inside the house while the house itself is unoccupied can substantially help to give the impression to a passer-by that the house is in fact occupied. It is sensible to use a downstairs room with a drawn curtain and sufficient light inside to suggest that the room is occupied. A light should not be left on solely in the hall - a thief may guess that the premises are unoccupied as it is not normal for the occupants to spend all night only in the hall!
There are many automatic devices available - simple and extremely sophisticated - that will turn lights on and off in random fashion and may even be set to control other electrical appliances such as the radio or television. Automatic switching will help to convince the casual thief that the house is occupied.
Most of the time security lighting will be all that is necessary to scare off a potential intruder. But do remember, lighting cannot work miracles. It is sensible to make sure that your physical defences - the locks, the bars and window bolts - will resist attack. Let your neighbours know that you are out, and if you are a member of your neighbourhood watch scheme so much the better. You can also inform your local police station that you are away.