“It is better to light one small candle than to curse the darkness.”Eleanor Roosevelt
Regardless of your industry, your company needs to account for these four critical elements for quality of light to achieve proper industrial lighting functionality and design:
- Distribution pattern
- Fixture mounting height
- Environmental conditions
The amount of illuminance required to properly light your industrial space is based on several parameters:
- Granularity of the task
- Presence of rotating equipment
- Age and eyesight of the operator
Lighting density for warehousing and storage is different than lighting requirements for food inspection and USDA compliance. The Illuminating Engineering Society publishes a complete list of illuminance criteria by area, by task as measured in foot-candles.
One foot-candle is defined as the light produced by one candle sufficient to saturate a one cubic foot of space.
Specifically, rather than measuring the amount of photons emitted by a light source (delivered lumens aka luminous flux), foot-candle is a measurement of the amount of light incident on a surface or area using a light meter. Readings can alternately be measured in Lux (1 Fc = 10.83 Lux).
In contrast, lumens are a measurement tool used to compare the amount of light a fixture emits. When considering fixtures, you’ll want to know how many lumens you need for your space. To determine how many lumens you need in a particular area, multiply the area square footage by the foot-candle requirement, for example, a 100 square foot space lit to 10-20 foot-candles requires 1,000-2,000 delivered lumens.
Fixtures can be specified to distribute light in various beam patterns, from very narrow, to medium or wide distribution patterns. Uniformity is important to ensure even industrial lighting, minimizing hot spots and dark spots.
Other considerations include veiling glare, obstructions from equipment, overhead cranes and ductwork. Not all areas of your facility require the same intensity of light due to various requirements, thus a combination of beam patterns may be required to provide flexibility. For instance, a racking aisle should employ a narrow beam angle in order to focus the light into a tighter space.
Fixture Mounting Height
Because light is measured by the amount that reaches a specific surface area in accordance with the Inverse Square Law, meaning luminance declines over distance, fixture mounting height has a significant impact on the photometric calculation. This distance determines the proper light levels delivered to the work plane.
For some applications, a fixture further away from the work surface may be ideal. However, supplemental task lighting could be just as effective. Mounting the fixture too close to the work plane causes lower uniformity (hot spots vs. dark spots) and greater glare. Mounting too far away leads to reduced efficiency of the selected fixture requiring more fixtures or higher energy consumption (wattage).
Fixture height may be impacted by various structural interferences, mounting configurations, shadows, accessibility for maintenance and overall uniformity.
Quality of light can be dramatically impacted by the characteristics of the environment. For instance, the luminance required for a space with highly reflective surfaces is lower than spaces where dark ceilings, walls and floors absorb light. Ambient temperature, moisture, and light loss factors like lumen depreciation, dirt depreciation, and haze and fog from industrial processes all impact your quality of light, as well as how long your fixtures will last. All of these conditions should be considered when you are selecting fixtures.
If the fixtures will be subjected to extreme hot or cold temperatures, harsh chemical washes during sanitation shifts, or salt and saline exposure, you need to select a fixture built to withstand these conditions. Light fixtures are rated according to various performance standards including NSF (food grade), Ingress Protection (IP – water and dust intrusion), impact, ambient temperature, and life expectancy. When you are considering FX Lighting fixtures, all of these details can be found on the product spec sheet, with most of them found on the Products page.
Achieving proper and efficient lighting throughout your space is a complex task with many variables to consider. The easiest way to do this is to contact us for a free lighting audit. Our industrial lighting experts will review your current lighting conditions and layouts, listen to your needs, and determine the most cost- effective course of action to bring you the quality of light you need. Request your free lighting audit today.
What’s the Easiest Way to Determine if You Have the Right Industrial Lighting? Get a Free Audit!
Instead of trying to factor in all of these considerations yourself, let us do it for you. We’ll review your current lighting configuration and needs and give you a cost-effective course of action to efficient, quality light.