Manhole cover (fire brigade)

The manhole cover is a chemical-resistant bag filled with water or sand, which is used by the fire service to prevent harmful liquids from entering the sewer system . The sack is placed on a manhole cover and filled with water, the weight of the water ensures that the manhole is tightly sealed. They therefore represent an alternative or a supplement to the gully quick release . Lately, manhole covers made of large magnetic foils have also been sold, which are simply placed on manhole covers and adhere to them. Often the top is striped red and white, on the one hand as a warning effect, on the other hand so that it is not forgotten after use.