Fire hydrants – If you live in a house and walk within 100 metres of your front door, chances are you will come across a fire hydrant sign. That little yellow ‘H’. They are there to show fire fighters the location of a water supply and are particularly useful when the hydrant cover is obscured.

The two numbers on the fire hydrant sign indicate the size of the water main (top number) and the distance from the sign (lower number).

Modern signs show these measurements in millimetres and metres, whereas older signs use inches and feet. Because the scales are so different (6 inches vs 150mm), there is no uncertainty whichever measuring system is used.

During the 10 years from 1975 onwards, most hydrant signs in Britain were changed from Imperial to Metric and the changeover continues to this day with surviving Imperial signs still requiring replacement.

No one know who invented the first Fire Hydrant because its patent was destroyed in a fire… ironically.

To comply with UK regulations, fire hydrants should be checked and maintained by professionals. Total Safe offers fire hydrant testing throughout Essex. Get in touch with us to arrange a free consultation.

Find out about Fire Hydrant testing from Total Safe UK.