Section 5.143. .Neutralizing storage and freezing houses

(a) Floors. The floors of a neutralizing storage and freezing house shall be covered with sheet lead, with all seams and joints lead-burned in a careful manner so that there are no crevices in which nitroglycerin may lodge. It shall also be so constructed as to be readily washed and drained. The lead floor covering on new buildings shall be extended at least three inches up each sidewall with rounded corners. A lead pan under the receptacle for holding nitroglycerin is acceptable in old construction in lieu of a complete lead floor covering.

(b) Operation. The operation of each neutralizing storage and freezing house shall conform with the following:

(1) The maximum number of regular employes in each house shall be three.

(2) Catch boxes shall be provided on the outlets for wash water.

(3) No charge of nitroglycerin shall be sent out of a house into a pipeline or gutter during the period in which a charge is being received.

(4) Floors shall be washed at the conclusion of work each day.