Complex sentence: A safety lamp is any of several types of lamp that provides illumination in coal mines and designed to operate in air that may contain coal dust, methane, or firedamp, all of which are potentially flammable or explosive.
Split into simpler sentences: A safety lamp is any of several types of lamp, which are designed to be safe to use in coal mines. These lamps are designed to operate in air that may contain coal dust, methane, or firedamp, all of which are potentially flammable or explosive.