Section 332.24. Ventilation [29 CFR 1910.94].

  These are department rules in addition to the requirements in 29 CFR 1910.94 : Laboratory fume hoods shall be operated and maintained in accordance with all of the following:

(1)  

(a) Except as provided in sub. (2) , a laboratory fume hood shall be operated at a minimum average face velocity of 100 feet per minute at one of the following positions:

1. A full open sash.

2. A sash stop position.

(b) The minimum face velocity shall be determined with the sash stop position no lower than 18 inches above the work surface.

(2)  A fume hood may be operated at less than an average face velocity of 100 feet per minute if all of the following conditions are met:

(a) A spillage rate of less than 0.1 ppm at 4.0 liters per minute gas release is achieved.

(b) A minimum allowable average face velocity of 40 feet per minute occurs at a full open sash position.

(c) A continuous flow meter with an alarm is provided.

(3)  

(a) A visual and auditory warning alarm shall automatically occur when a vertical sash fume hood is operated above a sash stop position.

(b) A visual and auditory warning alarm shall automatically occur when a combination vertical and horizontal sash fume hood is operated above a sash stop position.

(4)  A test shall be performed annually to determine the face velocity of each fume hood.

Cr. Register, February, 1999, No. 518 , eff. 3-1-99; am. (2) (a), (4) (c), (5) (a) and (c) 2., r. (2) (b) and Figure 32.24, renum. (2) (c) and (d) to be (2) (b) and (c) and am. (c), cr. (5) (d) and (6), Register, June, 2000, No. 534 , eff. 7-1-00; CR 01-139 : am. (5) (c) 1. Register June 2002 No. 558 , eff. 7-1-02; correction in (5) (a) 3., (c) 1. made under s. 13.92 (4) (b) 7. , Stats., Register December 2011 No. 672 ; CR 14-060 : r. and recr. Register August 2015 No. 716 , eff. 9-1-15.