(1) A substantial cover constructed to allow for ventilation shall be provided at the charging floor level and between the cupola shell and charging floor when employees are working inside the cupola and below the charging floor level.
(2) The area underneath cupola charging equipment shall be guarded to prevent material from dropping onto employees during charging operations.
(B) Dropping cupola bottom.
(1) The area underneath the cupola shall be free from liquid before the bottom is dropped.
(2) A whistle or other warning signal shall alert employees before the bottom is dropped.
(3) A block and tackle, wire rope, chain, or other mechanical means shall be used to drop the bottom.
(4) The area surrounding the operation shall be cleared of all employees at the time the bottom is dropped, except for the employee(s) pulling the pin or posts who shall be protected by shielding, protective clothing or protective equipment.
(C) Cupola bottom support.
(1) When the cupola is in operation, its bottom doors shall be supported by a drop leg and two adjustable screw props on a metal prop base set on a concrete or other fabricated footing of equivalent strength, provided that, where the bottom doors are supported by hydraulic door closers or equivalent, a drop leg or a door locking mechanism is required.
(2) Temporary supports, such as timbers, blocking, or shoring, shall be placed under the cupola bottom doors to prevent a premature bottom drop.
(3) Mechanical means shall be provided for raising the bottom doors of the cupola.