The Crime Prevention Website

Share:

Because of the wide variety of commercial premises it is difficult to be prescriptive about the type and amount of lighting required for yours. You are advised to seek advice from a professional lighting designer or engineer if you are intending to upgrade your lighting installation.  

Lighting is necessary for a variety of reasons and preventing crime, as you can see, is just one of them. The uses can include: 

  • Safety for staff working after dark
  • Safety for visitors to the premises
  • Supporting CCTV cameras
  • Illuminating car parks
  • Advertising and or enhancing the presence of the business at night
  • Deterring potential offenders
  • Detecting offenders

The effectiveness of external lighting

In terms of security,  lighting can only be expected to deter crime if the criminal fears that their illuminated presence on the site will be observed by responsive witnesses, either formal or informal.  These could be: 

  • On-site security guards and staff who take action (Formal)
  • Members of the public walking by or in nearby buildings who call the police (Informal)
  • A monitored CCTV system (Formal) 

It therefore follows that an isolated building, which has very little chance of being observed after the working day has ended, may not benefit at all from external lighting being left on at night. In fact, the opposite could be true as the lighting might assist the intruder. Interestingly, the absence of lighting may require the intruder to bring their own light and the presence of this unexpected light may be the very thing that is spotted by the unexpected, but responsive witness. Nothing is clear cut! 

Of course, the vast majority of commercial buildings will have the benefit of overlooking to a lesser or greater extent and so most will require some illumination at night. 

The places you might want to light 

  • Service roads
  • Well-used footpaths
  • Observable building elevations
  • Delivery and dispatch bays
  • Entrance and exit doors
  • Site entrances
  • Car parks (when occupied by vehicles)
  • Yards 

Things to consider when upgrading or installing external lighting 

If your business occupies a large site with yards and car parks I recommend you use the services of a qualified lighting design consultant (See Directory).  An expert consultant will discuss your requirements in detail and ensure that the lighting system is both fit for purpose and uses the most modern and efficient lamps, luminaires and switching for the individual purposes of each lamp. 

If your site includes service roads and footpaths you are advised to comply with the requirements of the British Standard for public lighting; BS 5489-1:2013. Bear in mind that your local authority may have ‘dark sky’ policies in operation to reduce carbon emissions and light pollution. You can check this out by contacting your council’s lighting engineer. 

If you are not using a lighting design consultant to help you then you should try to adhere to the following bullet points.  The various values for your lighting system that follow are recommended by the police initiative ‘Secured by Design’ in their publication Commercial Development 2015 

  • Make sure your new or existing lighting does not adversely affect an already installed or planned CCTV system
  • Co-ordinate your lighting with the landscape to avoid unwanted shielding of the lamps by trees and large shrubs and the casting of shadows
  • Ensure that lighting columns do not provide the opportunity for climbing a perimeter fence or building
  • Low level lighting of the type produced by shielded bollards will not provide sufficient light to make out someone’s facial features and unshielded types often project upward glare into the eyes and make it more difficult to see in the dark. They are therefore not suitable for security
  • Some buildings are lit from the perimeter at night, which in some cases may cause an intruder to cast a shadow onto a building; a useful application if the premises is protected from an external guard station
  • Where a security officer is located inside a building (often the reception area) ensure that the external lighting to the entrance is balanced with that for the inside in order that the officer can clearly see through a glass window or door onto the footway outside and not simply see their own reflection
  • Some lamps may require protection from vandalism and accidental damage
  • Best lighting installations provide uniform lighting levels with good colour rendition (you can easily tell the colour of a parked car) which is sufficient to cater for all after-dark activity around the site. The installation should not create dark shadows, too much glare or light pollution
  • In addition, try to achieve the following values for your lighting installation:
  1. An overall uniformity of light of at least 0.25Uo (25%) and preferably up to 0.4Uo
  2. Colour rendering of at least 60Ra (60%). The Colour Rendering Index, as referenced in BS5489, is a scale from 0 to 100, where 0 is a light source under which there is a complete inability to render colour and 100 is a bright sunny day enabling total rendering of the visible spectrum of light. You may hear the term ‘white light’, which is a reference to the fact that a whiter light enables better colour rendition. Research has found that people feel safer in the presence of whiter light, because it is more akin to natural sunlight. Less white light is required to satisfactorily light an area than non-white sources, such as low pressure sodium (the old orange street lamps)
  3. The actual levels of lighting (Lux) for the installation will be determined by what task is being undertaken under the artificial light.  The table below is taken from the Institution of Lighting Professionals and SBD’s downloadable PDF publication ‘Lighting Against Crime’, a very good reference for commercial security lighting 

Location or Purpose of Lighting

Lux

Office interior (for security only)

5

To support a monochrome CCTV camera

5

Private car parks

10

Exterior Rural location

10

To support a colour CCTV camera (low-light cameras may need less)

15

Exterior Urban location

20

Walkways

30

Loading bays

50

Light Pollution

Light pollution, which can include glare from floodlights and light spill onto a neighbour’s property and non-targeted light above 70 degrees can be a statutory nuisance and should be minimised. See the above publication and Light pollution and annoyance and their effects on this site for further information

The use of intelligent lighting systems can minimise energy use by both dimming and switching lamps and new lamp technology, such as LED lamps can be up to 80% more efficient than the standard street lamp 

Further information

Different types of Lamps (on this site)

Types of Luminaire (light fitting) (on this site)

Institution of Lighting Professionals (to contact a lighting designer)