Soldering of filled tins

The soldering of filled tins shall not be carried out in the filling shed but shall be done in a separate building not less than fifty feet distant therefrom. The soldering irons, unless electrically heated, shall be heated in a separate compartment from that in which the soldering takes place; fires used for heating solder bolts to be at least three feet above ground level. The opening between these two compartments through which the soldering irons are passed shall be at a height of not less than three feet from the ground and shall be provided with an iron shutter which can be lowered at once.