Wall hydrant
Wall hydrants are water extraction points installed in buildings that are intended for fire fighting .
description
In a mostly sealed wall niche on a valve, a rolled-up pressure hose with the associated jet pipe is connected. In Germany, this is usually done using a dimensionally stable pressure hose W through which water can flow when rolled up. The technology is standardized according to DIN 14 461. In Austria, risers and wall hydrants are standardized in TRVB S 128 2012 as “fixed extinguishing water systems, wet and dry” . For an initial extinguishing aid by the layman, dimensionally stable pressure hoses are provided on reels, the fire brigade can connect their hoses to an existing Storz-C coupling with a higher flow rate. For fire fighting by fire protection groups and company fire brigades (extended extinguishing aid), foldable hoses (fire hoses) rolled up on reels are sometimes available, which must first be completely unrolled before use.
Wall hydrants are supplied via a pressurized “wet” or dry riser . In the latter case, the water pump is started using a switch on the respective wall hydrant.
The current labeling of wall hydrants is based on ASR in conjunction with DIN EN ISO 7010; The rolled up fire hose with flames on the side is shown on the pictogram (see illustration). Due to drinking water regulations, the hydration must be labeled if it does not carry drinking water.
Wall hydrants are not only prepared for the fire brigade , but similar to a fire extinguisher, they are accessible to everyone in order to be able to fight a fire as it develops. In addition to the wall hydrant, a fire extinguisher, possibly a fire blanket and a manual fire alarm (formerly push-button alarm) are often attached. The space in front of a wall hydrant must always remain free.
In the standard DIN 14 461, Part 1, wall hydrants have been differentiated into types "S" and "F" since the 2003-07 edition.
TYPE "S" is limited to wall hydrants "for self-help". The fire extinguisher hose must be made of a dimensionally stable material (min. 3/4 ″). The required amount of water is 24 l / min at a flow pressure of 2 bar with a simultaneity factor of 2 wall hydrants. Deviating from the usual installation rules of DIN 14 461, these can therefore be connected with a nominal diameter of DN 25 (1 ″). According to BGV A8, the pictograms are to be provided with an additional "S".
TYPE “F” describes the wall hydrants “for self-help and for use by the fire brigade”. The fire hose can either be made of dimensionally stable material (min. 1 ″) or a fully synthetic C-42 pressure hose. The dimensioning of the risers is regulated in DIN 1988, while the required amounts of extinguishing water can be found in DIN 14 461, Part 1. At the last wall hydrant of the riser, 100 l / min (6 m³ / h) at a flow pressure of 3 bar with a simultaneity factor of 3 wall hydrants must be provided.
In recent years, wall hydrants have come under increasing criticism due to the increased demands on drinking water hygiene. Although this is also discussed marketing reasons very controversial even applies to wall hydrants first the grandfathering sampling of drinking water, as long as no findings regarding the drinking water hygiene has. Appropriate system separations must be provided for new installations and, if necessary, adjustments; the DIN EN 1717 and DIN 1988 regulations are to be applied as a guide.
literature
- Markus Ungerer (Ed.): Practical manual for operational fire protection . Schmidt-Verlag, Berlin 2010, ISBN 978-3-503-12083-3 .
