SUN SAFETY FOR CONSTRUCTION WORKERS — UV PROTECTION BEYOND SUNSCREEN

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Ontario construction workers spend more time in direct sunlight than almost any other profession. During the summer months, a typical roofer, labourer, or framer can accumulate 6 to 10 hours of UV exposure in a single shift — many times the amount that would cause sunburn in an unprotected person. Over a career, that exposure adds up to a dramatically elevated risk of skin cancer, premature aging, and eye damage.

Sunscreen is part of the solution, but it is far from the whole answer. Effective sun safety on a construction site requires a layered approach that includes clothing, scheduling, shade, eye protection, and awareness of how UV radiation interacts with heat stress.

Why Construction Workers Face Higher UV Risk

Outdoor workers receive 2 to 3 times more annual UV exposure than indoor workers. Construction amplifies this risk in several ways:

• Extended outdoor hours — most construction work happens during peak UV hours (10 a.m. to 4 p.m.), when the sun's rays are strongest
• Reflective surfaces — concrete, glass, metal cladding, and water all reflect UV radiation, increasing exposure from below and the sides, not just above
• Elevated work positions — workers on roofs, scaffolding, and upper floors receive more UV because there is less atmospheric filtering and more exposure area
• Limited shade — new construction sites often have no trees, overhangs, or structures to provide natural shade
• PPE conflicts — hard hats, safety glasses, and gloves are mandatory but do not always integrate well with sun protection accessories

Skin Cancer — The Numbers

Skin cancer is the most commonly diagnosed cancer in Canada. Outdoor workers, including construction workers, face a significantly higher risk than the general population:

• Non-melanoma skin cancers (basal cell and squamous cell carcinoma) are strongly linked to cumulative UV exposure over a lifetime — exactly the pattern construction workers experience
• Melanoma — the most dangerous form of skin cancer — is associated with both cumulative exposure and intense, intermittent burns
• Outdoor workers are 2 to 3 times more likely to develop squamous cell carcinoma than indoor workers
• The face, ears, neck, forearms, and backs of hands are the most commonly affected areas — precisely the areas left exposed on a typical construction worker

Skin cancer is highly treatable when caught early but can be disfiguring or fatal when it is not. A mole or spot that changes shape, colour, or size should be examined by a doctor promptly.

Sunscreen — Getting It Right

Most construction workers either skip sunscreen entirely or apply it once in the morning and forget about it. Neither approach provides adequate protection.

• Use SPF 30 or higher — SPF 30 blocks approximately 97 percent of UVB rays. SPF 50 blocks about 98 percent. The difference is marginal, but either is far better than nothing.
• Choose broad-spectrum — this means the product protects against both UVA rays (which cause aging and contribute to cancer) and UVB rays (which cause burns).
• Apply generously — most people use far too little. You need approximately one ounce (a shot glass worth) to cover exposed skin on the face, neck, arms, and hands.
• Reapply every two hours — and more frequently if you are sweating heavily, which construction workers almost always are. Sweat degrades sunscreen rapidly.
• Use water-resistant formulas — labelled "water-resistant 80 minutes" for the best performance during physical work.
• Do not forget the ears, back of neck, and lips — these areas are commonly missed and are among the most vulnerable to skin cancer. Use an SPF lip balm.

UV-Rated Clothing — Your Best Defence

Clothing is more reliable than sunscreen because it does not wash off, wear out, or require reapplication. Not all clothing provides equal protection, though.

• UPF-rated shirts and sleeves — Ultraviolet Protection Factor (UPF) clothing is specifically designed and tested to block UV radiation. A UPF 50 shirt allows only 1/50th of UV rays through. Many manufacturers now make lightweight, moisture-wicking UPF shirts suitable for hot weather construction work.
• Long sleeves are better than short sleeves — it seems counterintuitive in the heat, but a lightweight UPF long-sleeve shirt keeps you cooler than bare skin that is absorbing UV radiation and heating up. The fabric also wicks sweat.
• Neck flaps and hard hat brims — attachable neck shades (also called hard hat shrouds) clip onto the back of a hard hat and protect the ears and neck. Wide-brim hard hat attachments provide shade for the face and ears.
• Dark, tightly woven fabrics — in the absence of UPF-rated clothing, darker colours and tighter weaves block more UV than light, loosely woven materials. A white cotton T-shirt provides only about UPF 5 — far less than most people assume.

Shade Structures and Work Scheduling

Where possible, creating shade and adjusting schedules reduces UV exposure for the entire crew:

• Portable shade structures — pop-up canopies, tarps, and shade sails over break areas and stationary work stations. Even a simple tarp over a cutting station reduces UV exposure during repetitive tasks.
• Schedule intense outdoor work for early morning or late afternoon — UV intensity is lowest before 10 a.m. and after 4 p.m. Where project timelines allow, shifting the heaviest outdoor work to these windows makes a measurable difference.
• Rotate workers through shaded and unshaded tasks — alternating between outdoor and indoor work areas distributes UV exposure more evenly and gives skin recovery time.
• Use the UV Index forecast — Environment Canada publishes daily UV Index forecasts. When the index is 6 or higher (common in Ontario from May through September), extra precautions are warranted.

Eye Protection

UV radiation damages eyes as well as skin. Chronic UV exposure increases the risk of cataracts, pterygium (a growth on the eye's surface), and macular degeneration. Construction workers need eye protection that addresses both impact hazards and UV exposure:

• Safety glasses with UV400 protection — most CSA-certified safety glasses already block 99 to 100 percent of UV radiation, but verify this on the product label. UV400 means the lens blocks wavelengths up to 400 nanometres, covering both UVA and UVB.
• Wraparound frames — provide side coverage and reduce UV entering around the edges of the lens
• Tinted lenses for outdoor work — grey or brown tints reduce glare without distorting colours. Avoid excessively dark lenses that cause the pupils to dilate, potentially increasing UV exposure if the lens does not have proper UV filtering.

UV and Heat — A Combined Risk

Sun exposure does not just cause UV damage — it contributes directly to heat stress. A worker in direct sunlight experiences a radiant heat load that can increase their effective temperature by 10 to 15 degrees Celsius compared to a worker in shade doing the same task. This means that UV safety and heat illness prevention are inseparable on an Ontario construction site in summer.

When the UV Index is high, the heat is usually intense as well. The same strategies that reduce UV exposure — shade, scheduling adjustments, lightweight clothing — also reduce the risk of heat exhaustion and heat stroke. Treat them as one integrated program, not two separate checklists.

Make It a Habit

Sun protection on a construction site has to be as automatic as putting on your hard hat and steel toes. Keep sunscreen in your lunch bag or tool box. Attach a neck flap to your hard hat at the start of every summer. Wear UV-blocking safety glasses every day, not just when it is sunny — UV radiation penetrates cloud cover.

Your skin does not forget a single shift in the sun. Every burn, every hour of unprotected exposure, adds to your cumulative risk. The good news is that effective protection is simple, inexpensive, and available right now. Use it.