Good lighting is an important requirement for the activities of a warehouse or inventory & distribution facility, whether standalone, or part of an industrial complex. Putting items into inventory, accounting for them, retrieving and consolidating them for shipping are found in business operations of every type. The traditional concept of a warehouse has changed radically in recent years. Automated inventory control, bar coding, high rise racking, robotic forklifts, high speed conveyer systems, are just some of the new techniques being used to increase the throughput of these facilities.
Some typical areas within a warehouse building:
Open floor storage of large goods (rackless)
High rise racks (decks up to 100 feet high)
Rack spaces 3-12 feet wide, 8-30 feet high
Items loose, binned, or packaged
Rack and item labels of different sizes and legibility
Mobile racks on wheels or rails create different aisle configurations
Paperwork stands and computer terminals within the storage aisles
Cold storage areas
HazMat storage areas
Shipping & receiving
Equipment maintenance areas
The structural framework of industrial buildings, especially warehouses, forms interior spaces called “bays”. Selection of general lighting luminaires is based on the height of the bay and should provide more or less uniform illumination of the area :
Low-bay – bottom of luminaire is <18 ft. off the floor
Medium-bay – bottom of luminaire is 18-25 ft. off the floor
High-bay – bottom of luminaire is >25 ft. off the floor
The majority of tasks occur in the vertical plane
Provide 20-30 foot candles of uniform illumination on the vertical surface of goods stored on the racks
Horizontal illumination is a secondary concern but is important for navigation in the aisles and reading of pick tickets by forklift operators
Reflected glare affects readability and scanning accuracy.
Avoid clear plastic tape and wraps on packaged goods.
Light colored packaging and dark contrasting text labels provide better contrast and enhance readability
Glare from light sources should be avoided
Light sources, especially HID, should be shielded to avoid disability glare when looking up to tops of racks
Indirect luminaires combined with reflective ceilings produce good visual comfort especially when display screens are in use (workstations, handheld terminals, and on forklifts)
Aisles can be illuminated with classic high-bay HID luminaires (15 feet and above) Must be spaced close enough to eliminate dark areas between luminaires
Spacing can be increased when using low-bay luminaires or aisle-lighting luminaires with if an asymmetric light distribution pattern
Highly efficient T8 and T5 HO fluorescent luminaires can be used at mounting heights up to 30 feet. Typically installed in continuous rows along an aisle or individually mounted. (reflector, lensed, or open designs)
Warehouse spaces that are accessed intermittently provide opportunities to save energy. Motion sensors and control devices interface with HID and fluorescent multilevel ballasts to lower light levels when spaces are unoccupied by personnel or equipment.