Sodium hypochlorite, for example, is strongly corrosive to the skin and damaging to the eyes. However, the effects depend on the concentration of the solution used as well as the amount and conditions of use. The solution is alkaline due to the lye it contains. Sodium hypochlorite will create a lot of toxic chlorine gas if it comes into contact with acids. Sodium hypochlorite releases chlorine into the air also without any contact with acid. Smell is not a good indicator of the health risk associated with chlorine. The smell threshold is 0.2–0.4 ppm of airborne chlorine. The limit value for a temporary 15-minute exposure that must not be exceeded is 0.5 ppm of airborne chlorine. If there is any smell of chlorine, there is too much of it in the air, and work should not be done without a respirator.

Respiratory exposure must be prevented by spot removals, using a respirator and/or by changing the duration of work/working practices. If there is any smell of chlorine, use a full face mask with a B2P3 filter or the blower TH2B2P, TH3B2P or TM3B2P.

Mask eye protectors or safety masks must always be used when not using a respirator that covers the face. Due to the risk of getting solution containing chlorine in the eyes, at least 3 bottles of eyewash must be kept on hand when working. In case of accident, the eyes must be washed for 15 minutes and the washing must be continued for the whole duration of traveling to the doctor’s office.

In all cases, the respirator must be of a size and model that fits the face of the user well. Test the seal at least with your own breathing. Instructions (in Finnish) for putting on a half mask. Instructions (in Finnish) (PDF) for putting on a filtering half mask (FFP).

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The guidelines of the Finnish Institute of Occupational Health (FIOH) are drawn up together with the Ministry of Social Affairs and Health (SMAH) and the Finnish Institute for Health and Welfare. We also follow the publications of the European Centre for Disease Prevention and Control (ECDC) and the World Health Organization (WHO).

European Centre for Disease Prevention and Control (ECDC), COVID-19

World Health Organization (WHO), coronavirus