Want to improve health, safety, productivity and quality? Look at your workplace lighting

September 22, 2025

Jessica Bowes

Worker in a vest working in a factory.

There are some very compelling reasons for manufacturing employers to pay more attention to lighting in the workplace, says Nathan Birtch, Specialized Consultant (Ergonomics). “Poor lighting conditions in the workplace can compromise safety, adversely impact workers’ physical and mental health, and reduce quality and productivity. Well-designed lighting systems can help prevent these problems.”

How inadequate light affects health and safety

Slips, trips, and falls. Poor lighting impairs visibility, making it difficult for workers to spot hazards on the floor, such as spills, uneven surfaces, and obstacles, which can lead to slip, trip, and fall injuries, explains Nathan. “Stairways are particularly problematic,” says Nathan. “Low light can create shadows that impair a worker’s ability to detect changes in elevation.”

Struck by incidents. The likelihood of forklift/pedestrian incidents is heightened in low-light conditions. “Forklift drivers already have a limited line of sight because their view is blocked by various components of the forklift,” notes Nathan. “Poor lighting and visibility increase risks further, limiting the operator’s ability to detect objects or pedestrians.”

Musculoskeletal disorders (MSDs). Workers may adopt awkward postures to compensate for the lack of visibility, explains Nathan. “When workers can’t see their work clearly, they may hunch over, twist their bodies, or strain to get closer to a light source, which can result in neck, back, and shoulder pain. This can contribute to the development of chronic MSDs.

Health issues. With low light levels, the eye has to work harder to see and focus, explains Nathan, resulting in eye strain, headaches, eye fatigue and general fatigue. “Mood disorders can result from a lack of full-spectrum natural light, so it’s best to utilize natural light when possible.”

Other safety hazards. Poor lighting makes it hard to detect moving parts of machinery, identify cut hazards, assess the need for maintenance on machines and equipment, and read warning and information signs.

Causes of inadequate lighting

The solution to inadequate lighting depends on its underlying cause. Here are three possibilities:

Insufficient light or illumination. Illuminance refers to how much light falls onto a surface. It's measured in units called lux (lx). The amount of light needed depends on the job or task being carried out. Activities that involve detailed work require the highest level of illumination.

“For example, stairways, loading docks, and storage areas may range from 50-200 lx. For many industrial tasks with high contrast, a range of 200-500 lx is typical. For precision assembly and inspection, illumination levels jump to 750 and even up to 10,000 lx depending on the complexity and inspection requirements." For more information on appropriate levels of lighting for different tasks, check out CCOHS: Lighting Ergonomics - Survey and Solutions and American National Standards Institute/IES standard RP-7:Recommended Practice for Lighting Industrial Workplaces.

The wrong type, or the wrong number of, fixtures, luminaires (lighting units) or bulbs for the situation. “The brightness level may be correct, but if there are too few bulbs or the wrong fixture, overall light levels will be too low,” Nathan explains. “For example, a circular pot light will mostly cast light downwards but not wide, while a longer rectangular light bank will distribute light wider and more evenly.”

Improper workplace design. Placement of fixtures in relation to the work being performed matters. “For instance, if a storage rack is placed directly underneath the fixture, the product on the rack will likely block the light coming from the fixture. This could affect the ability of workers to move and place products safely, and read product labels.”

How to determine if you have a lighting problem

1. Do a walkthrough of your workplace to identify lighting risks. Nathan recommends using WSPS’ new Lighting Risk Identification Checklist. This resource will help you spot hazards related to the general workplace, equipment, and workers. For example, are there areas with dark spots or harsh shadows? Do workers performing detailed work have task-specific lighting that they can adjust as needed?

“Look for glare and flicker, which also affect workers’ health and safety,” says Nathan. Glare occurs when there is an excessive amount of light in the worker’s line of sight or reflected off a surface. It impairs visibility, making it difficult or impossible to see details and objects clearly. “For example, if a bright light source is positioned adjacent or in line with a safety dome mirror used by a forklift driver around corners and intersections, it may blind the driver to what’s ahead.”

Flicker occurs when light changes brightness very quickly, making it seem like it's flashing or fluttering. Flicker can cause problems like eye strain, headaches, difficulty concentrating, and fatigue. In some cases, it can create a stroboscopic effect, where moving machinery appears to be still or moving slowly, which can be dangerous.

2. Take a closer look at incidents that are happening in the workplace. “Look for the root causes of slips, trips, and falls, struck by injuries and MSDs,” recommends Nathan. “Could lighting be a contributing factor?”

3. Review worker feedback. Are workers reporting eye strain or headaches? Are they complaining that they can’t see what they are doing?

4. Assess the situation. “Get input from your in-house engineer, joint health and safety committee, or lighting contractor,” says Nathan. Ensure everyone is familiar with the recommended lighting levels in ANSI/IES standard RP-7:Recommended Practice for Lighting Industrial Workplaces.

“A light meter can help you understand if levels meet the standards. If your workplace does not have a light meter and someone to interpret the findings, WSPS consultants are available to help.”

5. Implement lighting solutions in phases. Starting with the most critical areas, ensuring proper positioning, even light distribution, and minimizing shadows, glare, and flicker. “Consider rolling out change in sections to evaluate the impact before rolling out to the entire facility.”

6. Develop an ongoing lighting program. “This doesn’t have to be onerous,” says Nathan. “Incorporate lighting considerations into your existing policies and practices. For example, add our checklist to the joint health and safety monthly inspection, and make sure your preventative maintenance team is checking bulbs, light fixtures, etc. on a regular basis.”

“It’s also important to increase awareness about lighting issues among supervisors, managers and workers,” says Nathan. “Everyone should understand the hazards that can arise, and how to report problems.” (For more on program development, check out the Proper Lighting in Industrial Work Environments guide.)

How WSPS can help

Consulting

A WSPS consultant can do a walkthrough of your workplace to help identify lighting issues that could lead to health and safety concerns. Connect with a consultant.

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