It’s natural to want to take advantage of sunny summer weather, but National UV Safety Month in July is a reminder that even nice weather demands precautions. July has the highest average UV index of the year throughout the United States, meaning that even a minor amount of time outdoors at the peak of summer brings high levels of exposure to ultraviolet rays. Especially for anyone who works outdoors, this can significantly increase your chances of developing skin cancer.

There are multiple types of UV rays, but the most relevant ones are UVA and UVB rays, both of which can penetrate skin and damage tissue. When you look for sun protection in any form, remember to ensure it guards against both types. The sun may be strongest during the summer months, but UV rays are present year-round, even on cloudy or overcast days. It takes as little as 15 minutes to damage unprotected skin, so following these guidelines is a worthwhile practice at any time:

• Reduce your time outside where possible
• Limit sun exposure during high-intensity hours, from 10 a.m. to 4 p.m.: if your shadow is shorter than you, the sun’s rays are strongest
• Take breaks in the shade
• Wear sun-protective clothing with a tight weave or high-SPF fabric
• Wear a wide-brim hat
• Choose sunglasses that offer 99-100% protection against both UVA and UVB rays

Sunscreen is an essential safeguard, but its effectiveness depends on choosing a strong enough formulation and applying it properly:

• A broad-spectrum sunscreen that blocks both UVA and UVB rays is a must
• Use a sunscreen with an SPF (sun protection factor) of at least 15
• SPF guards against UVB rays. To protect yourself from UVA light, choose products containing Mexoryl, Parsol 1789, titanium dioxide, zinc oxide, or avobenzone
• Apply at least 1 oz of sunscreen at least 20 minutes before going into the sun
• Reapply every 2 hours, regardless of SPF, and every time you get out of the water or have been perspiring heavily
• Don’t forget commonly missed areas like the scalp, ears, lips, neck, back of hands, and tops of feet
• Insect repellents may cause sunscreen to lose its effectiveness, so you may have to reapply more frequently
• The FDA requires sunscreens to remain effective for three years; throw out any bottle past that window, or with an unknown expiration date

Employers can assist outdoor employees by using tents, shelters, and cooling stations at worksites, providing sun protection products, and scheduling or rotating workers to minimize time spent in the sun.