are used for the ignition of gaseous fuel in gas combustion equipment, which works on the principle of ignition by high-voltage flashover. The central electrode must not be permanently positioned in the flame. The ignition electrode and the ionisation probe are usually positioned together in the combustion chamber of the gas combustion equipment - gas-fired boilers, instantaneous water heaters, gas ranges, cookers etc. Ignition electrodes can be used as ionisation probes and vice versa. However their layout should always be respected, i.e. the ignition electrode must be out of the flame and only the central electrode in the flame. Ignition electrodes and ionisation probes are manufactured of high-quality materials. The insulator is made of the OXAL ceramics with high Al2O3 content. Characteristic features of this material are high mechanical strength and resistance to thermal and electrical load (electric strength of the insulator is 18kV). The central electrode is made of a special fire-proof material (kanthal) which is resistant to high temperatures and electrochemical corrosion.