Final report of the Committee on Spray Coating, Chemical Section, National Safety Council, September, 1927 (1927)
National Safety Council. Committee on Spray Coating · Chicago : National Safety Council · leaf 24
17 REPORT OF COMMITTEE ON SPRAY COATING … Fortunately there is another type of respirator which 99.9 per cent. None of the filters tested gave such is based on a wholly different principle and which a degree of efficiency, the nearest approach to it being can be made both efficient and comfortable. This is obtained with 16 layers of…
