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How Hot are Hot Tubs?

How hot are hot tubs? In this article, we take a look at how hot tub temperature is important for the safety and wellbeing of bathers.
hot tub thermometer
For safety reasons, home hot tubs are designed to heat water to a temperature no higher than 40 degrees Celsius. However, most hot tub users find between 36 and 37 degrees to be an optimal temperature range for comfortable bathing.

40 degrees Celsius is the industry agreed maximum for several reasons. All of which relating to the health and safety of the individuals using the spa. The health and safety executive states that hot water used for showering or bathing above 44 degrees Celsius increases the risk of injury and fatality. While an average home spa temperature of 37 degrees Celsius is generally considered safe, the guidelines differ for children, pregnant women and those with certain health conditions. The HSE states that "The warm temperature of spa pools could pose a risk of ill health to users who are pregnant, have cardiovascular problems, or are subject to fits." The HSE also mentions that animal experiments conducted in the past have suggested that "prolonged immersion in water above body temperature can lead to delayed shock". In addition, the British and Irish Spa and Hot tub Association (BISHTA) state that "soaking in water over 40°C during hot tub use can increase the risk of heatstroke, or impairment of the body’s ability to regulate its internal temperature and even cause fatalities." However, BISTHA also state that there are many benefits of hot water immersion 29at safer levels (between 36 and 38 degrees).
woman in hot tub
How hot you like your hot tub is up to you, but if you choose to enjoy a soak at the hotter end of the safe range, keep your bathing time short and make sure to stay well hydrated before, during and after hot tub use. If you notice you feel dizzy or lightheaded after using the hot tub, consult your doctor and make sure to reduce the temperature and bathing time during your next hot tub session.
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