Secondary explosion protection measures (prevention of ignition sources)

Secondary explosion protection measures are defined as measures designed to prevent, as far as possible, potential ignition sources in components or parts of the plant where there is a risk of explosion. The following must be taken into account as potential ignition sources:

• Hot surfaces

• Flames and hot gases

• Ignition sources resulting from mechanical friction, impact and abrasion, including when using tools

• Electrical installations

• Electrical equalisation currents, cathodic corrosion protection

• Static electricity

• Lightning strikes

• Electromagnetic fields in the frequency range from 9 × 10³ Hz to 3 × 10¹¹ Hz

• Electromagnetic radiation in the frequency range from 3 × 10¹¹ Hz to 3 × 10¹⁵ Hz or wavelengths from 1000 µm to 0.1 µm (optical spectral range)

• Ionising radiation

• Ultrasound

• Adiabatic compression, shock waves, flowing gases

• Chemical reactions