Ultraviolet (UV) radiation is a known cause of skin cancer, skin ageing, and eye damage – and may also affect the immune system. People who work outdoors in agriculture and construction, as well as contractors in a number of fields, are the most likely of all workers to suffer health damage from exposure to UV radiation. Others may be exposed to UV radiation at work from non-solar sources such as arc welding, the curing of paints and inks, freight hauling, and the usage of equipment in hospitals and laboratories.
In relation to the non-solar sources of UV radiation, well designed engineering, administrative controls, and personal protective equipment can keep the risks to a minimum. However, outdoor workers who are regularly exposed to the sun for long periods of time need a more comprehensive strategy to minimize risks. This is because the sun can’t be controlled like other workplace exposure hazards.
Solar UV Radiation?
While there are no regulatory UV radiation exposure limits, employers still have a duty to warn their employees of ways to avoid and mitigate exposure in the workplace. Factors to take into consideration that affect UV radiation levels in your workplace include the following:
- Ground Reflection: Grass, soil, and water reflect less than 10% of UV radiation; fresh snow reflects as much as 80%; dry beach sand about 15% and sea foam about 25%. Even concrete can reflect and increase UV intensity. As UV radiation can neither be seen nor felt, it’s important that workers who have the potential to be exposed to intense levels of UV radiation are aware of the risks and are regularly reminded to take protective action.
- Sun Elevation: The higher the sun in the sky, the more intense the UV radiation. Therefore the UV radiation levels are highest around solar noon and in summer time.
- Latitude: The closer the equator, the higher the UV radiation levels will be.
- Cloud Cover: UV radiation can penetrate through light cloud cover, and on lightly overcast days the UV radiation intensity can be similar to that of a cloud-free day. Heavy clouds can reduce the intensity of UV radiation although scattered clouds have a variable effect on UV radiation levels, which rise and fall as clouds pass in front of the sun. The take-away from this is to not assume you are safe just because it’s cloudy.
- Altitude: At higher altitudes, the atmosphere is thinner and absorbs less UV radiation, meaning more is absorbed by workers on the ground.
- Ozone: Ozone absorbs some of the UV radiation that would otherwise reach the Earth's surface, different parts of the world have different thickness is ozone layers.
Based on these factors, solar caused UV radiation takes in both your physical location in the world, but also the surfaces your employees are working in and around, as well as the time of day. For more information and on UV indexes and interactive maps, the Environmental Protection Agency offers additional resources.
Prevent UV Exposure in Employees
There are a number of measures that can be put in place to control risks in the workplace. Ultraviolet radiation exposure is something that builds up over time, and precautions should be taken for short, intermediate, and extended exposure times. This would involve:
For outdoor workers, shade cover or canopies can be provided. If employees are driving, windows of vehicles should be tinted with UV-absorbing films. For non-solar sources of UV radiation, suitable engineering control measures include opaque barriers like polycarbonate material, metal, wood, and cardboard. Employers should also implement UV radiation blocking filters, dedicated rooms, and curtains as needed. Any UV enclosures or interlocks that are supplied by manufacturers for their equipment must always be used. For those working in laboratory settings, black lights, germicidal cabinets, transilluminators, and crossliner machines are the most common sources of UV radiation that needs to be shielded against.
For outdoor workers, when possible, reschedule work programs to be performed outside the peak UV radiation period with 2 hours either side of solar noon; when possible, move the jobs indoors or to shady areas or rotate workers between indoor and outdoor tasks to lessen each employee’s total UV exposure. For non-solar sources of UV radiation, appropriate hazard labels and signs should be used, helping to keep staff at a safe distance, and limiting the time during which UV radiation sources are switched on. Additional training of supervisors and employees should be taken for workers exposed to solar and non-solar sources of radiation.
Personal Protective Equipment (PPE):
If necessary, outdoor workers should be provided with protective clothing that is loose fitting, made of close weave fabric, and provides protection to the neck, lower arms, and legs. Hats should shade the face, neck, and ears, and have a wide brim, measuring 8-10 cm. If hard hats have to be worn, they should have attached neck flaps. Sunscreen should be a minimum SPF 15, and be broad-spectrum with zinc oxide and titanium dioxide, that blocks UVA and UVB, and be applied regularly and liberally to exposed skin. Sunglasses should be a close fitting, wrap-round design, and block at least 99% of UV radiation. For non-solar sources of UV radiation, arc welders, and medical equipment users in particular need to be provided with purpose-specific protective equipment.
Implement Preventative Safety
Protective measures should always be taken to mitigate hazard exposure in the workplace. UV radiation damages and injuries may not be as immediately noticeable as cutting or burning hazards, but are just as critical to employee health and safety. Repeated exposure without the proper guards and protective equipment in place can lead to lifelong debilitating conditions and even death from cancer caused by radiation. As this is a hazard that can occur in a multitude of indoor and outdoor workplaces, we encourage employers to enact the appropriate measures when necessary in training workers in UV best practices. If you’re looking to implement UV radiation labels and signs into your equipment or workplace, shop our collections today!