8749
1 Pertinent ambient standards for Antimony, Arsenic, Cadmium, Asbestos, Nitric Acid and Sulfuric Acid Mists in the 1978 NPCC Rules and Regulations may be considered as guides in determining compliance.. 2 Ninetyeight percentile (98%) values of 30minute sampling measured at 250C and one atmosphere pressure.. 3 Other equivalent methods approved by the .