49. Before firing a gas exploder or an air gun, the person responsible must ensure that
(1) a siren is sounded before the firing to alert workers of an impending firing in time to allow evacuation of an area within a radius of 8 m from the firing site;
(2) not more than 1 air gun is fired at one time;
(3) before the firing, an inspection is done to ensure that the area within a radius of 8 m from the firing site is clear of unauthorized workers;
(4) the pipes and hoses connected to the gun that are subject to high pressure are secured or equipped with safety chains to prevent whipping of the pipes or hoses when air pressure is injected into them;
(5) the air pressure in the air gun is less than 3.5 MPa; and
(6) the person in charge of the vessel or platform is advised that the firing is being carried out.