A steam boiler, with every fitting and attachment, is well made of sound material, strong enough, free of obvious defect and properly maintained. Each boiler has a suitable safety valve that no stop valve can isolate, set at the maximum permissible working pressure and mounted on the boiler or as near it as practicable; a stop valve to the steam pipe; a correct pressure gauge the attendant can see, carrying the maximum permissible working pressure in a distinctive colour; one or more approved water gauges, guarded where glass tubular and the pressure exceeds seven kilograms per square centimetre; where one of a range, a visible distinctive number plate; and means to attach a test gauge and a fusible plug or efficient low-water alarm (economisers and superheaters excepted as the section provides; lever safety valves need secured weights). Boiler attendants are properly instructed and hold a certificate of competence issued by the Commissioner, displayed in the boiler house while on duty and cancelled for negligence or incompetence causing an accident; nobody enters a boiler in a range unless steam and hot water inlets from other boilers are disconnected or their valves closed and securely locked with the single-key blow-off arrangement the section prescribes; and no work is done in a furnace or flue until it has cooled sufficiently. Every boiler and its fittings are given a thorough examination by an authorised person at least every fourteen months (the examiner may set a period up to twenty-four months) and after extensive repairs, cold with interior and exterior prepared and, where required, under normal steam pressure; on the first steaming after a cold examination a competent person inspects the fittings and safety valve setting and signs a certificate entered in the General Register before use; signed reports in the prescribed form, giving the maximum permissible working pressure together with any conditions, are completed within twenty-eight days; a used boiler is not used for the first time in a workplace until examined and reported on; a new boiler is not used without an authorised person's certificate giving its maximum permissible working pressure and describing the tests applied, kept available with the boiler marked to match; and a boiler is used only in accordance with the conditions of its examination report.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.