Commercial spaces are not equal and their lighting needs are as different as night and day. Take for example, a textile manufacturing factory. Very bright light is needed here as the workers have to make sure that the fabric colors, the stitching, and the finishing are perfect. An office, on the other hand, may not need very bright light as the tasks performed may not call for clarity and contrast.
Even if the textile factory and the offices are located in buildings with the same square feet, their lighting needs will never be equal. The activities carried out in the spaces dictate the light fixtures to be used to provide sufficient illumination.
When it comes to lighting, the last thing people think of is numerical figures. Why think of numbers when all you need to know is whether the light is bright enough or very dull? But like it or not, numerical figures play a crucial role in lighting.
The Occupational Safety and Health Administration (OSHA), requires workplace lighting to be measured in foot candles.
Just what is a foot candle and why is it so important in lighting?
A foot candle accurately measures how bright light is 1 foot away from a light source. It is the most common unit of measurement for lighting and is used by lighting professionals to determine light levels in indoor and outdoor spaces. In short, a foot candle measures the intensity of light in a space.
In this post, we’ll be giving foot candle recommendations for 5 different types of settings.
1. Offices and Interior Spaces
When an office is well-lit, workers are able to accomplish tasks safely and efficiently. Additionally, good light levels can help prevent eye strain, allowing employees to work comfortably for long periods of time. However, too much light is just as bad as too little light as it makes it hard for workers to do their tasks.
Since workers in an office have no way of measuring the intensity of light, there are some questions you should ask yourself if you are a building owner, a facility manager, or a decision-maker.
5 questions to ask yourself to find out whether the lighting in an office or indoor space is sufficient
- Are workers able to perform their tasks with ease?
- Do people frequently complain of eye strain and headaches as they work in their offices?
- Do the current lights hum or flicker, affecting employee productivity?
- Do the lights create bright spots, dark spots, or glare in offices?
- Are there objects or components that cast shadows?
The foot candles needed in offices and interior spaces are usually dependent on the tasks that are carried out. General office spaces only need 20 foot candles. But spaces where detailed tasks are carried out, like drafting, need plenty of light – approximately 50 foot candles.
Conference rooms need about 30 foot candles as visually challenging tasks are carried out in them. Doctors’ offices need even more light as complicated, intricate procedures are usually conducted in these rooms. 100-200 foot candles are needed in these offices.
Common rooms like lunch rooms and rest rooms do not need a lot of light. 15 foot candles are enough for lunch rooms while 18 foot candles are adequate for rest rooms. The interior spaces of general retail stores, car showrooms, and service areas require 50 foot candles. Department stores only need 40 foot candles to ensure people can easily see and locate products.
Consider Reflection and Shadows
While these are the recommended foot candles for these areas, lighting designers should also take into account the reflection caused by objects and components in interior spaces. Walls, furniture, and machines in a room can reflect up to 50% light while floors can reflect up to 40% light.
When installing lighting fixtures in an office, an electrical professional should avoid spacing the fixtures very widely as this may lead to the creation of shadows. Objects positioned between such lights may also be the cause of shadows.
Primary sources of light can also create shadows if they are positioned directly above or behind workers in an office. If you are installing lighting fixtures in an office, be sure to test the area’s lighting conditions or reconstruct the office layout if possible to ensure there are no shadows when the lighting fixtures are installed.
If light is unevenly distributed in an office or an indoor space, it creates dark spots in some areas. Because the lighting levels will be inconsistent, people’s eyes will have to constantly readjust to the light, and their eyes will get strained in the process. The lighting conditions of interior spaces can be improved by painting walls white, replacing traditional light fixtures with LED, and getting rid of tinted or damaged fixtures.
There are different types of warehouses: private warehouses, public warehouses, automated warehouses, climate-controlled warehouses, and distribution centers. Different types of activities are carried out in these warehouses, which means different light fixtures are needed. Areas that don’t see a lot of activity like storage rooms require 5-10 foot candles. Loading bays and inspection rooms, which see a lot of activity, need very bright light – 30-50 foot candles. Cold storage rooms, warehouse aisles, and open warehouses support 20 foot candles of light.
Warehouse workers have to handle products of different sizes on a daily basis. The size of the items usually dictates the amount of light required. 20-50 foot candles of light are needed in spaces where small objects with tiny labels are frequently handled. In areas where bulky items with big labels are handled, 10-20 foot candles are enough.
We know that foot candle measurements can be quite confusing for people who don’t have a lot of knowledge on lighting.
If you’re not a lighting professional, ask yourself these questions to know whether your warehouse or distribution center is well-lit.
- Can workers read labels without experiencing visual stress or squinting?
- Do machines or objects cast shadows and cause visual strain?
- Do machines, walls, and objects in the space reflect light?
- Are workers able to see all the signs around the warehouse?
The answers you come up with will help you to know the lighting needs of the warehouse space.
One of the most common warehouse tasks is identification. Workers have to read the labels and documents for products and materials. When installing light fixtures in a warehouse or a distribution center, a warehouse lighting expert must think of contrast levels to ensure they use the right fixtures. The reflective nature of machines, walls, and objects must also be considered to determine whether more or less foot candles are needed.
3. Manufacturing and Industrial Facilities
In factories and manufacturing facilities, some work is usually done by machines. The lighting in these spaces must be bright enough to enhance safety. If workers feel safe, they can focus on their jobs and get more work done. Spaces with printing machines and sheet metal processing machines require 50-100 foot candles. These places need bright light as visual stress can lead to accidents.
Storage rooms that house machine in-feeds and machines only need 5-10 foot candles as they don’t get a lot of activity. Areas where large products are manufactured or assembled only require 30 foot candles while areas where tiny products and materials are produced need 100 foot candles.
To know whether the light in a machining facility is sufficient, ask yourself these questions.
- Are workers able to see the machines and all their parts?
- Do the current lights cause visual strain, making it difficult for employees to work?
- Do the lights cast shadows on the machines, jeopardizing operators’ safety?
- Is the lighting technology affected by long periods of operation?
When it comes to machine lighting, two issues usually crop up: odd angles and contrast levels. Large levers, exit or output points, and deep indentations can prevent light beams from illuminating some areas of machines.
To steer clear of these problems, lighting professionals can install fixtures that generate light horizontally or powerful fixtures in the areas that are not lit by overhead fixtures. They can also install different lights (like overhead lights and diffused lights) to create good contrast levels in areas where light contrast is important.
4. Color Matching and Painting Facilities
Because of the detailed nature of the work carried out in these facilities, they usually have very high lighting requirements. But the specific nature of the work performed will determine the foot candles needed. In painting facilities where visual acuity is of utmost importance, 100-150 foot candles are adequate. However, the light fixtures must be mounted no higher than 3 feet.
20-50 foot candles are needed in spaces where simple spraying and normal hand painting are performed. But where fine hand painting and finishing are done, up to 500 foot candles may be needed. The complexity of the tasks will determine the exact foot candles required.
These 5 questions will help you to assess whether the lighting in a painting or color matching facility is enough.
- Do the existing lights cause dark spots, bright spots, shadows, or glare?
- Can people identify colors easily?
- Are labels and documents easy to read?
- Can workers operate machines and other equipment safely?
2 lighting details play a very important role in these facilities: Color Rendering Index and Color Temperature. Lights with a high color rendering index reveal the true colors of objects and those with a high color temperature look brighter.
5. Exterior Spaces
The longevity and efficiency of outdoor light fixtures depends on where they are installed. Outdoor spaces are continually affected by ever-changing factors that can wreak havoc on light fixtures. During the day, the sun may deliver adequate light to an outdoor area. At night, the same area may need bright light. Dark public areas support 20-50 foot candles as they need to be well-lit.
If you want to know whether the lighting in an outdoor area is adequate, here are 3 questions to ask.
- Are people able to see signs and objects from a distance?
- Do workers experience visual strain because the lights are too bright?
- Does the outdoor space look unsafe and gloomy?
The different activities performed in outdoor spaces usually determine the foot candles required. Spaces that need the least amount of light are building exteriors. Only 1 foot candle is needed in these spaces. But where safety is a priority, the number goes up to 3. Building entrances and enclosed parking lots (with area lighting) need 5 foot candles while open parking lots support 2 foot candles.
Gas station canopies require 13 foot candles to be adequately lit while pump islands need 20 foot candles. Other outdoor areas that need 20 foot candles are ATMs, active storage yards, gardens, piers, and the exteriors of car dealerships.
When installing lighting fixtures in any of these spaces, lighting experts should follow these recommendations and stick to the industrial lighting guidelines to ensure the fixtures they install are perfect.