Gas cylinder PKL against explosion 0.25 kg blue

PKL Indian gas cylinder, refillable, 0.25 kg, Indian manufacturing, company pkl, holding the Saudi Quality Mark (G). What is the thickness of the metal used to manufacture the cylinder? 1.45 mm for the 0.25 kg cylinder. What is the welding method? A mixture of copper and bronze in a continuous thermal furnace with a protective atmosphere. What is the type of safety valve in the cylinder? In case of explosion, it opens the safety release valve with automatic closure between 22-30 bar and closes when above 20 bar.