Light brightness requirements for common and industrial spaces differ greatly. To achieve consistent, bright environments, the fixture’s luminous flux (or lumen [lm], which is the SI unit of luminous flux) must be taken into consideration. By definition, the term “luminous flux” (lx) refers to the total amount of light energy emitted from a fixture in all directions.
The Illuminating Engineering Society of North America (IESNA) has published recommendations for lumen requirements in various locations. This article makes references to the IESNA Lighting Handbook for determining adequate lumen levels for various mainstream locations.
Lumen recommendations for manufacturing plants are heavily influenced by the type of product being manufactured in the location. The following covers specific lux values for mainstream manufacturing facilities:
· Glove manufacturing: knitting and sorting (1000-2000 lux); pressing, cuffing and sewing (2,000-3,000 lux)
· Hat manufacturing: dyeing, cleaning and refining (500-750 lux); forming, finishing and ironing (1,000-1,500 lux); sewing (2,000-3,000 lux)
· Jewelry and watch manufacturing: 2,000-3000 lux
· Leather manufacturing: cleaning, cutting, stuffing and stretching (200-300 lux); finishing and scarfing (500-750 lux)
· Explosives manufacturing: 200-300 lux for all types, such as generators, stationary dryers, boiling tanks and extractors
· Paper manufacturing: beaters and grinding (200-300 lux); finishing and hand counting (500-750 lux); inspections (1,000-1,500 lux)
· Electrical equipment manufacturing: 500-750 lux for insulating and coil winding
For special tasks that require close attention to detail, such as inspections, portable luminaries may be used to support such work on the location.
Assembly Work (Industrial)
Assembly work in industrial settings are classified, based on the difficulty level of the tasks. The following lighting levels are recommended for buildings where assembly work is conducted:
· Simple: 200-300 lux
· Moderately difficult: 500-750 lux
· Difficult: 1,000-1,500 lux
· Very difficult: 2,000-3,000 lux
· Extracting: 5,000-7,500 lux
Assemblies in wood working and processing facilities also have special lighting requirements. Saw frame and bench assembly requires 300 lux at a height of 3.3 feet. Turning, cutting, sawing and dressing requires 500 lux at 3.3 feet and polishing requires 1,000 lux.
Professional paint spray booths have very strict lighting needs due to the nature of work conducted inside the facility. Such requirement varies, depending on where one is in the building. For example, in paint processing rooms where dipping, simple spraying, hand painting and finishing takes place, 200-300 lux is required. For fine hand painting and finishing, lux levels could reach as high as 1,000-1,500. Extra-fine hand painting and finishing requires double the number of lux at 2,000. Rooms that are used for paint mix comparisons may utilize fixtures that are capable of producing 1,000-2,000 lux.
For general paint facilities, 200-500 lux is recommended. Automobile paint inspection works require between 3,000-10,000 lux at 3.3 feet. It is important to consider that paint booths, in addition to observing above average lux lighting levels, must adhere to special footcandle measurements.
Dock Loading and Welding
Dock loading locations are high traffic areas where equipment and products are loaded or unloaded to or from a transportation vessel, such as a truck, freight container or small vehicle. For loading and unloading on platforms, 200 lux is sufficient. Loading operations that involve freight car interiors may include fixtures capable of producing 100 lux.
Welding operations involving metals should be supported by 300 lux of maintained average illuminance. Welding orientation for workers may be conducted under 200-300 lux lighting conditions, while precision manual arc welding may be supplemented with 5,000-7,500 lux lighting levels.
Parking Lots and Surroundings of Commercial Buildings
Parking lots have special lumen requirements, depending on the type of commercial establishment it is connected to. For example, common businesses, such as convenience stores, restaurants, malls and other retail buildings, may incorporate 60 lx minimum at horizontal illuminance and illuminance uniformity ratio of 3:1 (average to minimum) on the parking structure pavement and high traffic parts of the location. Around the area, it is ideal to maintain 30 lx at ground level. Exit and entry points of the structure and the attached building- if any, may observe a minimum of 50 lx at the pavement. If security cameras are present on the site, 12 lx vertical luminance at five feet above ground level should be implemented.
For general parking facilities, two lx of minimum horizontal illuminance (five lx for enhanced security purposes); and one lx of minimum vertical illuminance (2.5 lx for enhanced security purposes) should be observed. When dimming lights to conserve energy, the minimum value should not be lower than one horizontal lux. Enhanced security may vary, depending on the personal preferences of the lot owner, with values reaching up to 10 lux. Luminaries found in parking lots are typically cutoff or semi-cutoff variants with flat-bottomed lenses. Small parking structures may use wall mounted fixtures that are attached to an adjacent building. When using this type of light, one must be wary of unsightly glare and light pollution.
Educational, Hospitals and Hotels
Some commercial and mainstream institutions, such as schools and hospitals, may benefit from lighting level guidelines set forth by IESNA. According to the organization, classrooms in educational buildings should incorporate 300 lux, while classrooms for adult education, nurseries and lecture halls may utilize 400 lux (maintained average illuminance). Computer rooms that are menu driven may incorporate 30 lux.
For hospitals, lighting requirements also vary. General ward lighting may support 300 lux, simple examination rooms- 500 lux and examination/treatment rooms- 1,000 lux. Lighting systems in hotels and restaurants may support the following illumination levels: dining room- 100 lux, buffet- 100 lux and kitchen- 500 lux.
Inside all of the facilities mentioned above, restrooms and toilets should be illuminated with fixtures capable of 300 lux maintained average illuminance. Stairs and corridors should support 50 lux lighting levels.
Office buildings may incorporate a wide range of illuminance levels in the location. Single and open plan offices should maintain 400 lux (average). Below covers other areas of offices and their corresponding lumen requirements:
· Conference rooms: 300 lux
· Training rooms: 500 lux
· Internal corridors: 200 lux
· Auditoriums: 150-200 lux
· Lobbies, lounges and reception areas: 100-200 lux
· Work stations: 500 lux
For work that entails precision and close attention to detail, light levels may reach 1,500-2,000 lux. By comparison, outdoor sunny conditions boasts roughly 10,000 lux. Locations next to open windows support approximately 1,000 lux.
According to the IESNA Lighting Handbook, walkways located next to well-lit roadways do not require the support of separate fixtures. But to promote safety and security, most walkways still require lights to ensure timely detection of cars, bikes and other pedestrians on the path. For Type A pathways that are adjacent to commercial areas, a minimum average horizontal illuminance of 10 lx is required (22 lx vertical illuminance for special pedestrian security). For residential walkways, two lx of minimum average horizontal illuminance is sufficient (five lx vertical luminance for special pedestrian security).
Type B walkways that are isolated from general roads may support five lx for both minimum average horizontal illuminance and vertical illuminance for special pedestrian security. While pedestrian pathways inside tunnels must support at least 43 lx of average horizontal illuminance and 54 lx vertical illuminance for special pedestrian security.
Below is a shortlist of lighting products from Larson Electronics: