During hot summer weather, many people—especially in Hong Kong—carry “cooling sprays” when going out to quickly cool down. However, emergency authorities have issued a warning: although these products feel refreshingly cold, they may carry three major health and safety risks, including the possibility of serious frostbite. So how should a cooling spray be used to avoid frostbite and other problems?
The “Cooling Spray” Effect: Why It Feels So Cold
Cooling sprays typically contain ingredients such as LPG (liquefied petroleum gas), ethanol, menthol (peppermint-like cooling agent), fragrance, and glycerin (in addition to water).
When you press the nozzle, LPG—stored under pressure as a liquid—quickly sprays out as a fine mist and rapidly vaporizes. During vaporization, it absorbs a large amount of heat, which cools the skin surface.
At the same time, menthol stimulates temperature receptors in the skin and mucous membranes. Your brain receives a strong “cooling” signal, creating a sensation that may be more intense than the actual skin temperature reduction—in other words, part of the “extreme cold” feeling is also a sensory illusion.
Three Hidden Dangers Reported by Emergency Authorities
1) Flammable and Explosive Risk
Ingredients like ethanol, propane, and butane are flammable. Once released into the air, if the mist comes into contact with heat sources or open flames, it can ignite and potentially lead to fire or even an explosion.
In addition, the canister is a pressurized container. If left in a consistently high-temperature environment, the liquid inside can vaporize rapidly, causing pressure to spike. In extreme cases, the can may become dangerously explosive.
2) Risk of Skin Frostbite (Cold Burns)
Because the spray absorbs heat very quickly, if you:
- keep spraying repeatedly on the same spot within a short period, or
- continuously spray one area for too long,
the chemical and cooling effect can accumulate, driving the local skin temperature down excessively. This can lead to frostbite (cold injury).
3) Skin and Eye/Mucous Membrane Irritation
If the spray accidentally reaches the area around the eyes or broken skin, the chemical ingredients can strongly irritate:
- the eye’s mucous membranes, and
- damaged skin.
This may cause skin injury, redness, congestion, or increase the risk of infection.
How to Use Cooling Sprays More Safely (3 Key Tips)
To reduce risk, emergency authorities recommend:
- Read the label carefully before use.
Do not spray heavily or continuously on the same skin area.
A safer approach is to spray the product onto clothing or a towel first, which reduces direct contact with skin. - Keep it away from flames and high heat.
This helps prevent ignition or explosion. - Do not spray in car cabins or other enclosed spaces.
Avoid using it where gas can build up, increasing danger.
