Hello doctor,The query is about sanded grout exposure. I am quite concerned about my girlfriend's exposure to silica dust. We were doing a home renovation. I left for about 1.5 hours while she was removing tile in a kitchen. When I had come back I saw she was removing grout with a grinder and no dust mask. The room was filled with dust in the air. The room is about 10x9 with 12\x80\x9d tiles. This makes for a total cut distance of 1100\x80\x9d with the grinder. Assuming a 1/8\x80\x9d cut with a depth of 3/8\x80\x9d and this works out to 51.56 cubic inches of dust released into the air. Assuming an average of 25 % silica content in the grout and weight of 38 g per cu inch for the dust, that is about 490 grams of silica dust releases into the air. The room was open to adjacent rooms so I estimated about 90 cubic meter space, wich would work out to 5.4 g/m^3. She was doing this for about an hour and a half so I estimate about 1 m^3 was inhaled. From what I have read this is really high-level exposure.Is my math wrong? Did I miss something? I am making her go to the doctor and we will monitor her health closely. I am really concerned this could lead to serious problems in the near future.
Hi. Looking at the history, it is quite a high-level exposure and it can cause some kind of pneumonitis feature called hypersensitivity pneumonitis or toxic dust syn ChatDoctor.  If she develops symptoms of a cough, breathlessness, better to get a CT thorax to see her lungs and if possible lung function tests also. Kindly get back if you need more information. 