Pennsylvania Code
Title 34 - LABOR AND INDUSTRY
Part I - Department of Labor and Industry
Chapter 5 - BLASTING, DEMOLITION, FIREWORKS AND EXPLOSIVES
Subchapter D - EXPLOSIVES
GENERAL PRECAUTIONS: EXPLOSIVE VAPORS
Section 5.91 - Construction of buildings

(a) Rooms or portions of explosives plants in which there are used, generated or found, explosive vapors and where persons are employed, shall be separated from other rooms or portions of plants by fire-resistive walls or partitions, pierced with only openings that are necessary except when the rooms or portions of plants consist of separate buildings. Where the material being used or which produces the explosives vapors does not exceed 10 gallons in quantity and is confined in safety cans, it is necessary only to prohibit the use of open flames, post danger signs and observe safe practices. Materials which give off explosive vapors may not be stored in workrooms where people are employed, unless the materials are stored in closed, properly vented containers. Where practical, safety cans should be used.

(b) Where materials giving off explosives vapors are stored in separated or underground storage systems outside of buildings, they may be distributed by pipelines throughout buildings where persons are employed.

(c) Openings necessary in fire-resistive walls shall be provided with fire-resistive doors. The doors shall be kept closed at all times except when in use to permit passage from one room or portion of a plant to another. On these doors danger signs shall be posted, warning against the carrying of matches or an open light and permitting the entrance of authorized employes or others designated by the manager or superintendent only.