Discuss on the factors which should be taken in consideration prior to the employ of respiratory protective equipment by employees when exposed to dusts, chemicals or decreased oxygen.
In brief describe what is meant by the term Nominal Protection Factor.
If a respiratory mask with the NPF of 9 is worn by a worker in a working atmosphere holding 45 mg/m³, determine the concentration of dust in air that the worker will breathe in the mask.
Under OSHA 2005, the Occupational Exposure Standard for total inhalable dust is 10 mg/m³, what must be the NPF of the mask that employees must wear to meet the required standard if the workplace air contains 160 mg/m³?
Selection of a proper fan can be complicated and must be done by a ventilation or fan expert. Illustrate out the criteria which should be considered in selection of fans appropriate for a workplace.