External Roof Top
Data centres often have extensive exterior areas with large plant items such as diesel powered generators, fuel storage and air-conditioners, combined with the pipework, ducts and cable trays that link them.
Lighting in these areas is required for security to prevent theft and vandalism, and also for maintenance and fault-rectification. Large items create shadows which make a general floodlighting scheme impractical, so lighting external plant can present a challenge to the designer. The best approach is to use strategically placed localised lighting. This can often be wall mounted, or mounted on the support structure.
Illumination Levels
There is no specific guidance for external plant areas in the CIBSE: SLL Lighting Guides, but there are correlating applications.
Extract from CIBSE: SLL Lighting Guide 1 - Industrial Environment 2018
| Application | Maintained illuminance (lux) |
|---|---|
| Section 4.5 Security Lighting | |
| Medium Risk Areas | 20 lux minimum maintained illuminance, uniformity 0.4 (min/average) |
| High Risk Areas | 50 lux minimum maintained illuminance, uniformity 0.4 (min/average) |
In areas where close work is needed, an illumination level as high as 200 lux may be needed. This is often achieved using local task lighting.
Choice of Luminaire
The Mercian is ideal because it offers excellent vertical illumination for locations with lower mounting heights.
The A-Line and Thoroproof can be mounted on the support infrastructure to provide higher illumination levels where needed. Both have external fixing options, so can be installed easily without compromising the IP rating.
