EEMUA 241 is a practical guide for managing the presence and use of portable self-energised electrical and electronic devices within potentially explosive atmospheres. It provides a structured approach which can be followed by site personnel supervising and managing the presence and use of portable self-energised electrical and electronic devices on a day-to-day basis. This publication provides guidance in relation to the electrical ignition risks within areas with potentially explosive atmospheres. It therefore includes: vapours and mists - such as petroleum products; gases - such as hydrogen; and combustible dusts - such as food products and cement. The guidance only covers electrical ignition risks from self-energised devices (including those powered by extra-low voltage). Therefore, mechanical sources of ignition and devices powered by mains electricity are not covered. However, some of the guidance within this document (such as Section 12) may have some useful guidance which can be applied to the use of equipment powered by mains electricity. The guidance only covers portable devices, and as such does not cover any fixed equipment within the plant (such as lighting), or isolatable equipment which is fixed to vehicles (such as reversing cameras). It also only considers industrial facilities and does not aim to provide guidance on the use of portable self-energised electrical and electronic devices in public areas such as service stations or transportation on public roads.