4. Permanent apparatus erected in the open air must be at least 15 feet from an occupied building.
5. Apparatus sheds must be fitted at their highest points with outlet ventilators of sufficient size; the ventilators leading straight through the roof into the open air. They must be so arranged that the escaping gases and vapours cannot enter rooms or chimneys.
6. The contacts of any electrical warning devices must be outside the apparatus shed.
7. Acetylene plants must be prevented from freezing by erection in frost- free rooms, or by the employment of a heating apparatus or other suitable appliance. The heat must only be that of warm water or steam. Furnaces for the heating appliance must be outside the rooms containing generators, their subsidiary apparatus, or holders; and must be separated from such rooms by fire-proof walls.
8. In one of the walls of the apparatus shed--if possible not that having a door--a window must be fitted which cannot be opened; and outside that window an artificial light is to be placed. In the usual way acetylene lighting may be employed; but a lamp burning paraffin or oil, or a lantern enclosing a candle, must always be kept ready for use in emergencies. In all circumstances internal lighting is forbidden.
9. Every acetylene installation must be provided with a main cock, placed in a conveniently accessible position so that the whole of the service may be cut off from the plant.
10. The seller of an apparatus must provide his customer with a sectional drawing, a description of the apparatus, and a set of rules for attending to it. These are to be supplied in duplicate, and one set is to be kept hanging up in the apparatus shed.
III. Rules for Working the Apparatus.
1. The apparatus must only be opened by daylight for addition of water. If the generator is one of those in which the entire charge of carbide is not gasified at once, addition of fresh carbide must only be made by daylight.
2. All work required by the plant, or by any portion of it, and all ordinary attendance needed must be performed by daylight.