Special Locations
G 4.1
Introduction, purpose and principles BS 7671: 2008 includes this Section 7 for fixed electrical installations inside and outside agricultural and horticultural buildings, including locations where animals are kept. It does not apply to residences or other locations such as shops, workshops or storage areas in agricultural premises. These locations are characterized by arduous conditions, and people usually working in a wet or damp environment, both indoors and outdoors. An increased risk of damage to the electrical installation and an increased risk of personal danger can come from a number of factors, including:
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the use, possibly widespread, of chemical cleaners and fertilizers; behaviour and nature of animals (stock and vermin); agricultural machinery; frequent wet and damp conditions; lower body resistance of livestock.
It should be noted that danger, including the risk from electric shock, particularly applies to livestock. In places where livestock is kept, there is a greater risk of electric shock to them due to their lower body resistance and more intimate contact with the general mass of earth. It can often be seen in milking parlours that cows will not pass from one place to another where they sense a small potential difference between their front and rear legs.
G 4.2
Requirements and guidance The requirements of the section are summarized in Table G 4.1. As well as Table G 4.1 the following notes and guidance are provided. As applies generally to special location areas, protection by the use of obstacles, placing out of reach, non-conducting locations or earth-free equipotential bonding is not allowed in agriculture/horticulture due to the extra risks involved in such wet and exposed locations, as operators are usually non-technical staff (ordinary persons). Wiring systems and electrical equipment and accessories must be suitable for the location and environment of their use. Arduous conditions including animal housing, cleaning chemicals, wash down with hoses, vermin, physical impact damage
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G