Seventy watt SON’s are suitable for general ‘dusk to dawn’ asset lighting sited to light vertical surfaces of areas of a building of interest. There is also an issue with light pollution. However, to optimise the effect fittings must be close spaced due to the small angle of illumination making them costly to deploy. Glare lighting provides an alternative around a perimeter due to its high deterrence factor and its effect of concealing security personnel on patrol, whilst affording them the advantage of observing intruders. In perimeter and general lighting applications, a mounting height of 10 metres allows the use of a variety of luminaires in an energy efficient manner Moreover, siting needs to avoid shadows and illuminate the ground outside the fence evenly at a minimum of 3 lux. Ideally, in perimeter lighting applications they should be mounted on columns placed two metres within the fence line to negate their use as a scaling aid. They are ideal for dawn to dusk application as their slow strike time, to reach full brightness, prevents their use in event driven applications. SONs are energy efficient, characteristically 100 lumens per watt, long life expectancy 20,000 plus hours, and provide quality illumination even in fog. SONs provide a reasonable colour rendition although biased towards yellow, and when correctly sited they provide realistic uniform illumination. When applying security lighting schemes, normally 100 watt High Pressure Sodium (SON) is used for perimeter lighting and car parks, they may also provide both an operational and security use when deployed as general site lighting. The other factors to consider include light pollution creating shadows or dark areas, which could provide concealment for intruders uniformity of light levels, avoiding low illumination areas that assist miscreants whilst inhibiting security response teams.įennelly JL, (2013) recommended ‘foot candle’ lighting levels for given security applications, which have been converted into the following lux figures: Area Colour rendition – the ability to produce accurate colours.Start-up time to full brightness and restart time.According to CPNI (2009), several factors influence the choice, such as: The attributes of each lighting type also need careful appraisal for suitability to an application. In other words, what is the objective of implementing the security lighting? What do we want to achieve? Security is optimised when applications are mixed to complement each other, as each scheme has pros and cons that need consideration as part of an operational requirement. IR lighting is reserved exclusively for use with CCTV. Event activated – detection device or human.With the exception of IR lighting, covert or discrete – which is reserved exclusively for use with CCTV systems – lighting with a high Colour Rendition Index CRI is generally preferred for security applications as it makes make the illuminated scenes look more normal.ĬPNI (2009) suggests security lighting for the following applications: The primary lighting types for security purposes are high pressure sodium (SON), metal halide, quartz halogen and infra-red (IR) or non- visible lighting.ĭue to significant advances in light Emitting Diode LED lighting technology, they are becoming popular in both security and general lighting applications, while standard incandescent bulbs are being phased out in favour of more energy efficient, devices such as compact fluorescent, LED or Halogen filled Incandescent. Now winter is approaching and the dark nights are drawing in it is a poignant time to revisit the subject of lighting for security purposes. The summer clothes are packed away, the holidays are over and children returned to school as the summer ends. He is also a member of the Security Institute and Security Leaders Technology forum and the author of a number of published security articles. Through his dedication and leadership, 2020 obtained industry approval with the SSAIB and Quality, Environmental, and Health and Safety accreditations.Peter is a member of the Security Systems and Alarms Inspection Board (SSAIB), a UKAS accredited Certification Body, and its representative on the British Standards Institute (BSI) technical committee responsible for drafting European CCTV Standards. Over 20 years as MD of multi-award-winning security system integrator 2020 Vision Systems, the company achieved a high standard of recognition and the patronage of many respected organizations. Peter is an expert in the physical security industry having spent 35 years gaining considerable knowledge and understanding of security technology and the principles and practices of protecting people and assets, along with the ethics necessary for leading a respected company.
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