An investigation of an ignition of flammable gaseous mixtures with mechanical sparks

•A new method for testing of mechanical spark hazards of materials was proposed.•Various gases (hydrogen, acetylene, LPG, methane, etc.) and materials were tested.•A probability of an ignition was determined.•A criterion of spark safe materials was proposed.

This article describes a method for testing the safety of construction materials with respect to mechanical sparks (spark safety). This method was tested on examples of various materials and flammable gases. Hydrogen, acetylene, petrol, methane and LPG were used as the flammable gases. Various types of steel, aluminium, and copper and aluminium alloys were used as the construction materials. On the basis of the experiment a criterion for spark safety was proposed.