Before you buy a hot tub for your backyard or step into those warm waters at the spa or gym, make sure you know a bit about their safety.
Warm water soothes your body for a few reasons. The heat widens blood vessels, which sends nutrient-rich blood throughout your body. Warm water also brings down swelling and loosens tight muscles. And the water’s buoyancy takes weight off painful joints.
A dip in the hot tub might also help your mental state. Research shows they can promote relaxation and ease stress.
Hot Tub Risks
These warm water whirlpools can pose some risks if you’re not careful.
Between 2000 and 2014, outbreaks from treated pools and hot tubs were linked to more than 27,000 infections and eight deaths in the United States. When hot tubs aren’t cleaned well, their moist environment is the perfect breeding ground for bacteria.
Pseudomonas, one type of bacteria that thrives in hot tubs, causes infections of the hair follicles and skin. Symptoms include red, itchy bumps on the belly and areas covered by your bathing suit. These bumps can pop up anywhere from a few hours to a few days after you take a dip. The same bacteria cause an infection known as swimmer’s ear.
Hot Tub Use in Pregnancy
Hot tubs might not be safe for pregnant women because they increase body temperature. Research finds that pregnant women who use a hot tub more than once or for long periods of time are more likely to have babies with neural tube birth defects like spina bifida or anencephaly.
Be cautious when using a hot tub if you have heart disease. When you soak in hot water, your body can’t sweat. Your blood vessels instead need to widen to cool you off. This makes your blood pressure drop. In response to falling blood pressure, your heart rate speeds up.
This isn’t a problem for healthy people, but if you have heart disease, it can strain your heart.
Hot Tub Safety Tips
To stay safe, follow these tips:
Ask your doctor. If you’re pregnant or you have a health condition like heart disease, ask your doctor if it’s safe for you to get into a hot tub.
Check the cleanliness. Ask the hotel or gym how often they clean their hot tub, and whether they keep the pH and chlorine concentrations at levels the CDC recommends (a pH of 7.2-7.8, and a free chlorine concentration of at least 3 parts per million). If the water looks murky or slimy, don’t get in.
Turn down the heat. A temperature of 100 F should be safe for healthy adults. Anything over 104 could be dangerous. Turn it down another couple of degrees if you have a medical condition.
Limit your time. Don’t stay in the hot tub for longer than 10 minutes. If you feel dizzy, overheated, or unwell, get out right away.
Watch where you sit. Don’t sit too close to the heat source. Keep your head, arms, and upper chest out of the water to avoid overheating, especially if you’re pregnant.
Stay hydrated. Drink water while in the hot tub to cool off your body. Avoid alcohol, which can dehydrate you.
Don’t go from hot to cold. Don’t jump straight from the hot tub into the pool to cool off. The cold water could shock your system and spike your blood pressure.
Wash off afterward. Take off your bathing suit and shower with warm water and soap as soon as you finish.
Sitting in water above normal body temperatures can cause drowsiness which may lead to unconsciousness and subsequently result in drowning. The U.S. Consumer Product Safety Commission (CPSC) recommends that water temperatures never exceed 40 degrees Celsius. A temperature of 37 degrees is considered safe for a healthy adult. Soaking in water above 39 degrees Celsius can cause fetal damage during the first three months of pregnancy.
It is also recommended to install residual-current devices for protection against electrocution. The greater danger associated with electrical shock in the water is that the person may be rendered immobile and unable to rescue themselves or to call for help and then drown.
Hot tubs and spas are equipped with drains that can create powerful suction and between 1980 and 1996, the CPSC had reports of more than 700 deaths in spas and hot tubs, about one-third of which were drownings to children under age five. In the same period 18 incidents were reported to the CPSC involving body part entrapment.
To reduce the risk of entrapment, US safety standards require that each spa have two drains for each pump, reducing the amount of suction. From 1999 to 2007 there were 26 reports to the CPSC concerning circulation entrapments hot tubs and spas, including three deaths.
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