IES Recommended Lighting Levels for Commercial and Industrial Spaces

Adequate lighting is essential for any commercial or industrial space, as it directly impacts the safety, productivity, and overall effectiveness of operations. Whether you are beginning new construction, dealing with aging fixtures, or considering an energy-efficient retrofit, it's important to assess your facility's lighting needs carefully. One of the first steps in this process is determining how much light each area requires. The Illuminating Engineering Society (IES) provides optimal lighting level recommendations for various industrial and commercial spaces. We’ll walk you through how much light your space should receive and touch on some important factors to consider when planning your business’s lighting design.

The Illuminating Engineering Society (IES) is a nonprofit organization that sets standards and provides guidelines for optimal lighting practices in indoor and outdoor environments. Their handbook Lighting Applications Standards Collection compiles the recommended practices for lighting various spaces such as offices, libraries, hospitals, museums, and sports facilities. The following units of measurement are commonly used when discussing lighting levels: 

• Footcandles: A footcandle (fc) is a unit of illuminance that measures the amount of light hitting a surface. It is defined as one lumen per square foot.
• Lumens: Lumens (lm) measure the peak total calculated output, sometimes called intensity or brightness, of a light. Most light fixtures and lighting solutions will advertise their total lumen output.
• Lux: Lux (lx) measures the amount of luminous flux measuring lumens per square meter. As a general rule of thumb, 1 fc is equal to 10.76 lux. Footcandles and lux are measurements of the same thing, with lumens measuring per unit area.
• Vertical illuminance: Vertical illuminance is the amount of light that falls on a vertical surface. This measurement is particularly important for spaces where substantial activity occurs across a vertical plane, such as in sports fields and tall warehouses.
• Horizontal illuminance: Horizontal illuminance, is the amount of light that falls on a horizontal surface.

The following list shows the IES-recommended footcandles (lumens per square feet) and lux (lumens per square meter) for a variety of commercial and industrial spaces. Please note that this is a shortened list of commercial locations. For a complete list of locations and their average illuminance levels, review the IES Applications Standards.

When shopping for light fixtures or lighting solutions, the lumen measurement will most likely be listed on the product listing, so you will need to know how many lumens your space requires. To find the total lumens necessary for your space, multiply the room's square footage by the recommended footcandle amount. 

You can divide the total lumens by the number of fixtures you desire to find the average lumen value of each fixture. Or, you can divide the total lumens by the lumen value of your current lighting fixture to see how many total fixtures you need.

For example, let’s say you have a 600 ft² food service kitchen. Based on the recommended lighting levels in the chart, multiply 600 x 50 and 100 = 30,000-60,000 lumens for the total kitchen space. If you wanted your space outfitted with 12 evenly distributed fixtures, for example, you would need to find lights that emit 2,500-5,000 lumens.

The IES also provides recommended footcandles for indoor and outdoor sports arenas. Venue sizes are broken down into four categories based on the following criteria:

• Class I Facilities: Venues with a spectator capacity of over 5,000
• Class II Facilities: Venues with a spectator capacity under 5,000
• Class III Facilities: Venues with some provision for spectators
• Class IV Facilities: Venues with limited or no provision for spectators

Lighting designers must find a combination of fixtures that emit the total recommended lumens of the given space. The ideal lighting design utilizes a balanced number of fixtures or lighting solutions that evenly distribute light around the necessary space and create a functional environment. Other additional aspects should also be considered while creating a lighting design.

Keep in mind that industrial and commercial spaces with tall ceilings must account for the decrease in light intensity that occurs when the light source is moved further away from the ground level. The photometric diagram of our 300W UFO LED High Bay below shows how the average footcandle decreases as the beam width increases. You may need to choose a light fixture with a greater lumen value than recommended to ensure the footcandles that reach the working area do, in fact, meet the recommended brightness.

We provide photometric diagrams for our commercial and industrial lighting fixtures on our product pages.

Based on the IES lighting guidelines and the total lumens per square foot, an appropriate number of lights must be chosen for the intended space. However, certain lighting layouts may cause increased hotspots and overly bright areas. 

Let’s use the food service kitchen above as an example. Remember that the space requires 30,000-60,000 lumens. If a smaller number of light fixtures were chosen to light the kitchen, for example, 6 central lights emitting 5,000-10,000 lumens each, then there would most likely be extreme hotspots under each light fixture due to the intensity of the light. However, by doubling the amount of light fixtures and cutting the necessary lumens emitted by each in half, you can get a better overall light distribution and coverage. 

Take into account any vertical or horizontal surfaces that will require adequate lighting. For example, warehouses with tall shelving units will need top-to-bottom lighting coverage, while schools and offices must have enough evenly distributed overhead lighting to eliminate shadows on desks and tables. The position and type of light fixture you choose will directly impact how these vertical and horizontal surfaces are illuminated.

The correlated color temperature of your lights may factor into the overall perceived brightness of the space. Cool white light (5000K and up) typically appears brighter and provides clearer illumination for areas that require focus and concentration. If the suggested overall lumens for your space is relatively low, a warm white light might provide a more comfortable and mild effect.

Lighting with a high color rendering index, or CRI, is required for different commercial spaces. Areas that need high color accuracy, such as art galleries, museums, and retail stores, must utilize specialized lighting that mimics the color accuracy of natural light. A light with a CRI of 80+ is considered to have a Good CRI, and lights with a CRI of 90+ are considered to have a High CRI.

Many LED lights now feature selectable wattages which adjust the total brightness. If you are unsure which wattage will be best in your space, choosing a fixture with selectable wattage will allow you to increase or decrease the brightness during installation. This is helpful if you want to try various brightnesses while buying only one fixture or if you need to adjust the fixture brightness later down the line.

If you are updating the fixtures in your business with newer lighting solutions like LEDs, you may be tempted to use the same wattage as your current lighting when finding a replacement fixture. However, since LEDs use significantly less energy to emit the same brightness levels as metal halides, fluorescent lights, and halogens, use the equivalent wattage to find a comparable fixture. This ensures the lighting levels of your space stay the same during a light system upgrade.

Certain lighting fixtures are best suited for specific commercial and industrial spaces based on the average ceiling height, activities performed, footcandle recommendation, and overall aesthetic. The IES recommends the following fixtures for the specific applications listed above.

High bay fixtures emit wide beams of powerful lighting that provide sufficient lighting to the ground levels, even from high mounting locations. These fixtures are ideal for assembly facilities, food service facilities, gymnasiums, and stores as they cover wide, open spaces. There are two main types of high bays: UFO high bays and linear high bays. Your choice of high bay type will mainly depend on the layout of your space.

Troffer panels and recessed downlights provide a sleek lighting solution that evenly distributes light. Hospitals, gymnasiums, offices, schools, stores, and certain food service facility locations utilize these lights as they provide sufficient lighting for activities that require increased concentration or focus.

Deep recessed downlights help reduce glare in offices, schools, and other spaces where eye strain is common. These fixtures can be retrofitted to replace outdated lighting or installed in new construction projects.

Powerful stadium lights are designed to emit bright lighting for indoor and outdoor sports arenas. Sports field lights feature advanced optics that reduce glare, minimize hotspots, and focus light on specific areas within the stadium. Based on their placement around the arena, they provide sufficient vertical and horizontal illuminance to illuminate all angles of the playing field.

At Industrial Commercial Lighting, we are dedicated to supplying high-quality commercial fixtures. Each and every one of our products is rigorously tested in our in-house test lab to verify the specifications listed in its IES file are accurate. Our trained lighting technicians also compile in-depth photometric data sheets of all the metrics we measure. This ensures our lighting solutions are the right fit for your space. You can find these files in the Documents section on each product description page.