Staying safe in the sun and water



The dawn of summer ushers in fun and relaxation. It’s the season we forge cherished memories of vacation adventures with our family and lounge with friends by the pool or at a backyard cookout. But hotter temperatures and water proximity bring the need to protect our bodies from the heat, sun, and potential accidents. 

To get a rundown on steps to take to be safe this summer, we spoke with Dr. Minal Moharir, Clinical Assistant Professor of Medicine, Stanford University Occupational Health Center; Yong C. Kim, Assistant Director, Occupational Safety and Health program, Environmental Health & Safety; and Jennifer Cobarrubias, Associate Director of Aquatics, Stanford Recreation & Wellness.

There is no defined amount of safe sun exposure, even on cloudy and cool days.

Anytime your skin is exposed to the sun’s ultraviolet (UV) rays, you’re at risk for damage. UV rays are an invisible type of radiation that comes from the sun, tanning beds and sunlamps and that can damage skin cells and cause skin cancer.  

There are three types of UV rays: 

  • UVA is believed to damage connective tissue and increase the risk for developing skin cancer
  • UVB penetrates less deeply into the skin, but can still cause some types of skin cancer
  • Natural UVC is absorbed by the atmosphere and does not pose a risk

Dr. Moharir says that protection from UV rays is important all year, not just during the summer when it’s hot and sunny.

“UV rays can reach you on cloudy and cool days, and they reflect off of surfaces like water, cement, sand and snow. In the continental United States, UV rays tend to be strongest from 10 a.m. to 4 p.m. daylight saving time, which is 9 a.m. to 3 p.m. standard time.”

She points to the UV index, which forecasts the strength of UV rays each day. If the UV index is three or higher in your area, protect your skin from too much exposure to the sun. Although it varies depending on skin type, you can experience sunburn in a matter of minutes if the UV Index Scale is too high.

Unprotected sun exposure increases your risk of skin cancer.

Skin cancer is the most common cancer in the United States, with the most common types being basal cell carcinoma, squamous cell carcinoma, and melanoma. Indicators of skin cancer may include:

  • Irregular borders on moles (ragged, notched, or blurred edges)
  • Moles that are not symmetrical (one half doesn’t match the other)
  • Colors that are not uniform throughout
  • Moles that are bigger than a pencil eraser
  • Itchy or painful moles
  • New moles
  • Sores that bleed and do not heal
  • Red patches or lumps

Protect your skin — and still get vitamin D — with sunscreen.

Spending time outdoors is linked with greater well-being.1 It’s a great way to be physically active, connect with nature, reduce stress, and get vitamin D. You can work and play outside without raising your skin cancer risk by protecting your skin from the sun.

Dr. Moharir says sunscreens provide protection by absorbing, reflecting or scattering the sun’s rays, and they may contain chemicals that interact with the skin to protect it from UV rays. You can use a sunscreen’s sun protection factor (SPF), a rating of the sunscreen’s effectiveness, to determine how long the sunscreen will protect you before you need to reapply. Multiply the SPF number by the number of minutes it takes for you to burn.

Dr. Moharir gives the example that if you normally burn in 20 minutes and apply an SPF 15 sunscreen, multiply the two (20 X 15) to find that you’ll be protected for about 300 minutes (or five hours). 

“You should always wear sunscreen with at least SPF 15, no matter what your skin color. Even people with very dark skin can burn and develop skin cancer. Sunscreens with SPF numbers higher than 15 may work well for people who have lightly pigmented skin, live at high altitudes, or work or play outdoors much of the day.” 

SPF only refers to UVB protection. To protect against UVA, look for sunscreens that have Mexoryl, Parsol 1789, titanium dioxide, zinc oxide, or avobenzone.

Of note is that sunscreen, even when thickly applied, does not compromise vitamin D.2 In fact, vitamin D levels improve after applying sufficient levels of sunscreen during a week-long vacation at a location with a high UV index.

Proper and regular sunscreen application is key.

To get the most protection from your sunscreen, apply at least one ounce at least 30 minutes before going outside to all parts of your skin that will be exposed to the sun, including your ears, scalp, lips, neck, tops of feet and backs of hands. Reapply sunscreen at least every two hours and each time you get out of the water or sweat heavily.

Throw away sunscreens after one to two years, since they lose potency (you can check the expiration date on the bottle). Some sunscreens may lose effectiveness when applied with insect repellents, and you may need to reapply more often. Remember that sunscreen performance is affected by wind, humidity, perspiration, and proper application.

If you’re taking medication, ask your doctor or pharmacist if it will make your skin more sensitive to the sun. Certain antibiotics, birth control pills, diuretics, antihistamines, and antidepressants can increase one’s sensitivity to the sun’s rays. Some people may have an allergic reaction to sunscreen and may need to try a different sunscreen brand or see a dermatologist. 

Shade and clothing can protect your skin, too.

Your best bet to protect your skin is to use sunscreen or wear protective clothing when you’re outside—even when you’re in the shade. However, staying in the shade under an umbrella, tree or other shelter reduces your sun exposure somewhat, and Dr. Moharir recommends taking breaks in shaded areas when you’re outside. 

Dr. Moharir advises wearing long-sleeved shirts and long pants and skirts, when possible, to protect against UV rays. Clothes made from tightly woven fabric offer the best protection. If wearing this clothing isn’t possible, try to wear a T-shirt or beach cover-up. Dry clothing is best, as a wet T-shirt offers much less UV protection, and darker colors have higher protection than lighter colors. Finally, sun-protective clothing meets international standards certifying its sun protection.

Wide-brimmed hats with side panels offer the most protection because they shade your face, ears, and back of neck. Like clothing, a tightly woven fabric, like canvas, works best for sun protection and darker colors may be more effective. Avoid straw hats with holes that let sunlight through, and if you wear a baseball cap, be sure to protect your ears and back of your neck with other clothing, sunscreen, or by staying in the shade. 

Sunglasses protect your eyes and the skin around your eyes, as well as reducing the risk of cataracts. Sunglasses that block both UVA and UVB rays offer the best protection. Most sunglasses sold in the United States, regardless of cost, meet this standard. Wrap-around sunglasses work best because they block UV rays from sneaking in from the side.

Apply first aid if you get a sunburn.

Dr. Moharir explains that sunburn is not immediately apparent, and symptoms usually start about four hours after sun exposure, worsen in 24-36 hours and resolve in three to five days. Symptoms include:

  • Red, tender, and swollen skin
  • Blistering
  • Headache
  • Fever
  • Nausea
  • Fatigue

Eyes can become sunburned and will appear red and feel dry, painful, and gritty. Chronic sun exposure to the eyes can cause permanent damage, including blindness. 

Dr. Moharir recommends the following first aid for sunburns:

  • Take aspirin, acetaminophen, or ibuprofen to relieve pain, headache, and fever
  • Drink plenty of water to help replace fluid losses
  • Comfort burns with cool baths or the gentle application of cool wet cloths
  • Avoid further exposure until the burn has resolved
  • Use of a topical moisturizing cream, aloe, or 1% hydrocortisone cream may provide additional relief


If blistering occurs:

  • Lightly bandage or cover the area with gauze to prevent infection
  • Do not break blisters. This slows healing and increases risk of infection
  • When the blisters break and the skin peels, dried skin fragments may be removed and an antiseptic ointment or hydrocortisone cream may be applied


Seek medical attention if any of the following occur:

  • Severe sunburns covering more than 15% of the body
  • Dehydration
  • High fever (>101 °F)
  • Extreme pain that persists for longer than 48 hours

Stay healthy and safe in the heat.

According to Y. Kim, when the weather gets warmer, it’s important to be aware of a few key factors that can increase your risk of heat stress and more serious health-threatening events such as heat stroke.

“As the weather gets hotter, it’s important to be more careful about prolonged and strenuous activity, especially if your body has not had time to gradually adjust to the heat.  If you’re traveling to regions with extreme humidity, even temperatures in the low 80’s can trigger heat-related illness — so it’s important to take steps to stay safe.”

Y. Kim points to guidance from the Centers for Disease Control (CDC) on heat safety. To prevent heat-related illness, the CDC recommends:

  • Wear lightweight, light-colored, loose-fitting clothing
  • Stay in an air-conditioned place as much as possible
  • Limit outdoor activities to the morning or evening when it’s coolest, and rest in shady areas so your body can recover
  • Decrease exercise during the heat, and if activity makes your heart pound and leaves you gasping for breath, stop all activity and get into a cool area or shade to rest
  • Wear sunscreen as sunburns can dehydrate you and make it harder for your body to cool down
  • Drink more fluids and avoid sugary or alcoholic drinks
  • Replace salt and minerals with a sports drink since heavy sweating removes salt and minerals from the body

It’s important to know
the signs of heat exhaustion and heat stroke and steps to take if you or someone else is experiencing symptoms. Get immediate medical help if you are throwing up, your symptoms worsen or last longer than one hour.

Enjoy your time at the pool and beach while practicing caution.

Cobarrubias says that water safety doesn’t differ between pools, lakes and beaches, but there is more to look out for at lakes and beaches due to being unable to see the bottom, currents and waves, and if there are any obstructions.

She recommends life jackets approved by the U.S. Coast Guard for adults who aren’t strong swimmers and children while emphasizing that water wings for children, while popular, are not sufficient to protect your child against drowning. 

Life jackets expire and can become damaged. Be sure the jacket isn’t expired and that the jacket is intact without torn fabric or loose or broken straps. Cobarrubias explains that when life jackets deteriorate, they feel heavy and like they’re full of water because the foam starts to absorb water. She also says to only wear jackets that will support your weight and that they are not effective if you are under or over the recommended weight of the jacket. 

Cobarrubias promotes swim lessons for adults and children. Often, adults may be embarrassed to get swim lessons, but she explains that swim instructors are non-judgmental and there to help. Stanford Recreation & Wellness will be offering private swimming lessons to Stanford employees and their family later this summer. All instructors are certified water safety instructors, and lessons will stress important water safety skills.

Even if you are a strong swimmer, you’re not less likely to be in danger, as anything can happen. She points to how the weather, environment and other surroundings all affect swimming conditions, so it’s important to practice caution no matter your skill level. To that end, never swim alone, and if you see someone who needs help, you should “reach or throw, don’t go.” 

“Don’t go in after them. Reach for their hand, throw them a float or something to grab 

onto or get a lifeguard.”

In addition to the above, the National Safety Council (NSC) recommends swimmers keep the following safety precautions in mind: 

  • Don’t go in the water unless you know how to swim; swim lessons are available for all ages
  • Learn CPR and rescue techniques
  • Make sure the body of water matches your skill level; swimming in a pool is much different than swimming in a lake or river, where more strength is needed to handle currents
  • If you do get caught in a current, don’t try to fight it; stay calm and float with it, or swim parallel to the shore until you can swim free
  • Swim in areas supervised by a lifeguard
  • Don’t push or jump on others
  • Don’t dive into unfamiliar areas
  • Never drink alcohol when swimming; alcohol is involved in about half of all male teen drownings, according to


Rip currents are responsible for most rescues that lifeguards perform and can form in any large open water area. Stay at least 100 feet away from piers and jetties, and if you get caught in a rip current, stay calm, don’t fight it, and swim parallel to the shore or float or tread water. The American Red Cross has an instructional video on surviving a rip current and recommends the rip current survival guide by the National Oceanic and Atmospheric Administration (NOAA).

Teach children about water safety.

Going to the pool is at the top of every child’s mind during the summer, but children aren’t known for being forward-thinking about safety. The USA Swimming Foundation reports that 74% of drowning incidents for children younger than 15 occurred in residential locations. Drowning is the second leading cause of preventable death through age 15 and the number one cause of unintentional death for children aged one to four.3

The NSC notes that younger children are more at-risk for drowning, and often drowning occurs because the caregiver was distracted and “only looked away for a second.” To protect your child against drowning, be aware and in the present moment with your child and take the following precautions:

  • Never leave your child alone near water; if you have to leave, take your child with you
  • Find age-appropriate swim lessons for your child, but keep in mind that lessons do not make your child “drown-proof”
  • Lifeguards aren’t babysitters; always keep your eyes on your child
  • Don’t let children play around drains and suction fittings
  • Ensure all public and private pools and spas you visit have compliant drain covers
  • Install proper barriers, covers and alarms on and around your pool or spa
  • Never consume alcohol when operating a boat, and always make sure everyone is wearing U.S. Coast Guard-approved life jackets 
  • Don’t underestimate the power of water; even rivers and lakes can have undertows
  • Always have a first aid kit and emergency contacts handy
  • Get training in CPR
  • If a child is missing, check the water first

Cobarrubias adds that kids (or anyone) should be warned about the dangers of hyperventilation and extended breath-holding, noting that when kids play a game to see who can hold their breath underwater the longest, it’s possible they could pass out and drown. 

She also reminds that kids, even those who are good swimmers, get tired in the water and their energy flags, making them prone to accidents.

“It’s important to give kids a break from the water so they can rest and regain some energy. They can take the time to go to the bathroom, reapply sunscreen or eat a snack.”

Finally, she advises teaching children about what can go wrong in the water, and if they’re older, educating them on how to say “no” if they find themselves with friends who may want to do something unsafe, such as play in the ocean by a pier or swim out too far.

“If kids don’t feel comfortable doing something, you can teach them to say that their parents said they couldn’t do whatever the action is, or if they don’t want to say ‘my mom says I can’t do that,’ giving them other language, such as, ‘I’m not comfortable doing this,’ and teaching them that it’s okay to walk away if they feel pressured to do something they know isn’t safe.

Cobarrubias recommends the Swim app by the American Red Cross to teach kids about water safety in a fun, engaging way that will resonate with them.




July 2021