Section 5 Protection from electric arc hazards within electrical equipment

5.1.1 An assessment is to be carried out in accordance with Vol 2, Pt 9, Ch 4, 5.2 Hazard identification and assessment 5.2.1 for all electrical equipment within which an arcing fault could occur, such as:

• harmonic filters;
• motor starter panels;
• semiconductor converters;
• switchboards, section boards and distribution boards;
• transformers.

5.2.1 An assessment is to be carried out to identify the hazards and their consequences for personnel resulting from electric arcs within the electrical equipment identified in Vol 2, Pt 9, Ch 4, 5.1 General 5.1.1. The purpose of the assessment is to demonstrate that the design incorporates adequate measures to reduce the risk of injury to personnel should an arcing fault occur within the electrical equipment, and that this will help to ensure both personnel and ship safety.

Details of the following are to be submitted:

1. each task to be performed, e.g. switching, equipment maintenance, instrument observation or cleaning;

2. the hazards to personnel that could result from an electric arc occurring during each task, and the hazards to personnel that could result from the electric arc;

3. the methods to be used to help to prevent electric arcs;

4. the methods to be used to protect personnel from hazards resulting from electric arcs within electrical equipment.

5.3.1 The following calculations are to be conducted and used in the hazard identification and assessment:

1. Calculations of the maximum current that would flow through an electric arc between each conductor and its adjacent conductor, and between each conductor and the exposed conductive parts of the enclosure, in the case of an arcing fault;

2. The maximum incident energy at the intended working distance in the case of an arcing fault;

3. The distance from each conductor at which the incident energy would be 5 Joules per centimetre squared in the case of an arcing fault when the enclosure door is open.

These calculations may be made in accordance with IEEE Standard 1584, IEEE Guide for Performing Arc-Flash Hazard Calculations, or another relevant Standard acceptable to LR.

5.4.1 It is to be demonstrated that, where provided, arrangements to detect arcing faults function correctly.