[Determining the level of yttrium oxide-coated silicon nitride in the air of the work area]. / OPredelenie nitrida kremniia, pokrytogo pksidom ittriia, v vozdukhe rabochei zony.

To measure the concentrations of yttrium-oxide-coated small-dispersed silicon nitride plasma powder, the air was aspirated at the amount of 10-15 litres per min through the AFA-XP filter. The filter was limed in a platinum crucible, the residuum being alloyed with Na2CO3, Na2B4O7, NaNO3 in ratio 10:5:1. The alloy was transferred into solution in which the silicon content was assessed through reactions with ammonium molybdate, and yttrium--through reactions with arsenaso III. The sensibility rate for silicon was at 0.07 mg/m3.