Anyone who has had a hot or cold stone massage knows how relaxing and therapeutic the pressure and temperature of the smooth stones can be on an aching body. The warm stones help relax tight muscles and melt away stress, while the cool stones help soothe sore spots and bring down inflammation. Though all of this sounds like pure bliss, it’s important to feel safe as well as relaxed during your treatments. While patients have always wanted to know about the sanitization of the stones and the heating and cooling equipment, now they ask a new question: “Is it safe to use stones during a massage in the era of COVID-19?” The answer is yes.

Due to new safety protocols, heating pads and other heating devices that were once used to treat patients are not allowed. This is due to the fact that the soft fabric coverings and the electric heating devices cannot be properly sanitized between each patient. Stones on the other hand are sanitized continually in a bleach water bath. 

The hot stones are contained in a roaster set at 200ºF in a water bath containing 1-¼ teaspoons of bleach per 6 litres of water. The combination of bleach and heat results in an unfriendly environment for bacteria and viruses, including the COVID-19 virus.(1)(2)  I currently double the amount of bleach in the cold water bath to ensure proper sanitation of the cold stones. All of these measurements meet with Environment Protection Agency guidelines for properly preventing contamination of drinking water.  A regular check of chlorine levels (recommended level is 4 ppm) is done between patients to ensure that an adequate amount of bleach or free chlorine (active chlorine available to continuously kill bacteria and viruses) is in both the hot and cool stone water baths.(3) I also add Spa Shock to the hot water bath to maintain the chlorine strength while reducing chlorine odour and preventing the harsh drying effect that bleach can have on the skin.(4)

In addition to sanitization procedures, the agitation, or act of rubbing, when using the stones during treatment also facilitates the destruction of the virus. This further helps to prevent contamination from the virus if it were ever to land on the skin or on the stones outside of the roaster.

At the end of day, the roaster and cooler are drained, and the stones scrubbed in a cleaning solution of 10 ml of bleach per 1 litre of water with Dawn dish soap original formula and then rinsed and dried.(5)  The bleach-to-water ratio is what they use at my son’s daycare for proper sanitation of their toys and playground with the added degreasing power of Dawn. The roaster and cooler are also wiped down in the same cleaning solution to ensure proper sanitation protocols and maintenance of the equipment.  

 A little known fact about bleach:  when using a solution mixed with bleach, it is only active for about 24 hours if used for sanitation purposes.(5) So any homemade disinfectant solution with bleach needs to be disposed of and remade the next day for proper sterilization.  Bleach also comes in strengths of; 6% and 8.25%, so if you are making your own solution, make sure to check the first, as bleach is hard on the skin and more is not necessarily better. Lastly, bleach expires, so be sure to check the expiry date to ensure the bleach you are using is still effective.  

When I first took the class for hot/cold stones I was excited to add another technique to my toolbox. Stones effectively treat TMJ and sinus congestion, as well as increase lymphatic flow and reduce hyper-tense muscles.  This treatment has become a great asset to my practice and many patients request hot/cold stones to be added to their therapeutic massages. I feel safe using them during this time, and always have, as all of these sanitation and safety protocols were implemented prior to COVID-19. It has always been important to maintain a clean and safe treatment environment; the only difference now is my many outfit changes. You’ll have to book a massage and tell me which one you like best!

If you are interested in booking a massage with Nancy Na, RMT, email us at for more information. 


1. Water, sanitation, hygiene, and waste management for the COVID-19 virus. UNICEF: World Health Organization; 2020

2. Disinfecting with Chlorine & Chloramine.  Centers for Disease Control and Prevention; 2017

3. Disinfection with chlorine.  Centres of Disease Control and Prevention; 2015

4. What Should Chlorine Levels Be in Swimming Polls and Hot Tubs?: Pool Calculator; 2020 

5. Preventing Illness in Childcare Settings:  BC Health Planning; 2003