Arc Flash Standards: EN 50110

The requirement for a risk assessment for electrical arcs is laid out in the general requirements for working procedures in section 6.1.1:

Working procedures are divided into three different procedures: dead working (see 6.2), live working (see 6.3), working in the vicinity of live parts (see 6.4). All of these procedures are based on the use of protective measures against electric shock and/or the effects of short-circuits and arcing. For further details on arc hazard, see B.6.

Annex B.6 provides some more information on electrical arcs and the hazards they pose. Persons working in the vicinity of electrical installations are considered to be exposed to hazards caused by an electrical arc. It lists the following requirements for risk assessment:

In the case that any work in the vicinity of an electrical installation or under live conditions is necessary, a risk assessment should be done. To carry out planned work the general technical preventive measures, e.g. plates and doors, should be opened or even to be removed for a certain period of time. As these actions are part of maintenance and repair work, hazards due to electric arcs cannot be completely eliminated for the foreseeable future and suitable measures should be met. Additionally, other workers such as operators may be within reach of electrical arc hazards. These risks should be included in the risk assessment.

The first sentence suggests that risk assessment is not required for dead working. It is recommended to do so anyway, as verification of the absence of voltage can lead to exposure to electrical arcs.

For selection of PPE the standard refers to additional standards.