Document oemvd2rprkg9oE8214ezBR5K7

APPENDIX "B" DOW CHEMICAL U.S.A. January 2, 1987 LOUISIANA DIVISION P. O. BOX ISO PLAOUEMINE. LOUISIANA 7076S-01 SO BOA 366-8000 Lynn Dugas, 3801 /Milton Rudolf, 3801 INDUSTRIAL HYGIENE FUME HOOD EVALUATION AT PROMIX On December 30, 1986, the laboratory hood at Promix was evaluated for face air velocity using the Alnor Model 8525 Thermo Anemometer. Laboratory hoods are classified according to their hood face velocities with the sash at an 18-inch opening. Laboratory hoods are grouped into four classifications: Class A (high toxicity use) Carcinogenic, toxic, highly flammable. 125 - 150 ft/min average hood face velocity. 100 ft/min minimum reading. Class B (normal lab use) Toxic or flammable 100 ft/min average face velocity. 80 ft/min minimum reading. Class C (low toxicity use) Non-toxic or non-hazardous compound. 75 ft/min average face velocity. 50 ft/min minimum reading. Class D (Inadequate) The lab hood was determined to be Class B, but just barely so. The filter should be checked to see if it is plugged and the belts should be checked to make sure they are not slipping. William E. Ledford Industrial Hygiene ck AN OPERATING UNIT OF THE DOW CHEMICAL COMPANY DO 108097 COIMFIDENTIA