Abstract: An explosion proof electrical enclosure has a relieved joining flange at the junction between the cover and the body of the enclosure. The relieved portion provides an area reducing the bolt load in the event the enclosure is subjected to an internal explosion. As a result, fewer bolts may be used to join the enclosure, reducing the cost of the enclosure, increasing the convenience of access to the enclosure and reducing the labor required to remove or install the cover. The cover of the enclosure has increased stiffening structure at the corners so that the bolts in the corners of the enclosure may be eliminated.

Abstract: A safety latch assembly for a circuit breaker panel board. The panel board includes a cabinet in which one or more circuit breakers are mounted behind a panel member, the breakers being operable between ON and OFF positions by an actuating member which in turn is operated by a handle mechanism mounted in the cover of the cabinet. The safety latch assembly includes a movable member operable in response to movement of the actuating member. The movable member has means engaging a portion of the handle mechanism preventing engagement of the actuating member by the handle mechanism, and thus preventing closing of the cabinet cover to which the handle mechanism is mounted, when the actuating member of the breaker is in the OFF position. Means are also provided for engaging the handle mechanism with the actuating member of the breaker in the ON position, preventing disengagement of the handle mechanism and the actuating member and removal of the cover.