Technical Booklet E Fire Safety·Page 166
Fire mains types and supply
Fire mains can be dry type (normally empty, supplied by pumping appliance) or wet type (kept full of water from building tanks and pumps). Wet systems should have emergency replenishment capability from a pumping appliance.
Fire mains may be of the dry type which are normally empty and are supplied through hose from a fire and rescue pumping appliance. Alternatively, they may be of the wet type where they are kept full of water and supplied from tanks and pumps in the building. There should be a facility to allow a wet system to be replenished from a pumping appliance in an emergency.
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