The changeover continues to this day as surviving Imperial signs require replacement. All hydrant fittings are standardised, perhaps partly as a result of an incident on the night of 14 November 1940, when it is said that fire appliances were sent from Birmingham to assist with a conflagration in Coventry only to discover that the two sets of hydrant fittings did not match.Дuring the ten years after 1975, most hydrant signs in Britain were changed from Imperial to metric. Note that the upper number relates to the size of the water main serving the hydrant and not the size of the hydrant itself. This does not appear to have deterred at least one supplier from incorporating units into the design: Because the orders of magnitude are so different (6 inches versus 150 mm) there is no ambiguity whichever measuring system is used.вЂ™ Modern signs show these measurements in millimetres and metres, whereas older signs use inches and feet. Mounted on a small post or nearby wall etc., the two numbers indicate the size of the water main (top number) and the distance from the sign (lower number). Yellow вЂњHвЂќ hydrant signs indicate the location of the hydrants. вЂIn the United Kingdom and Ireland, hydrants are located in the ground. Wikipedia provides a succinct summary of the facts about fire hydrant signage: They show fire fighters the location of a water supply, and are particularly useful when the hydrant cover is obscured, perhaps by snow or a parked vehicle. If you live in a house, you will probably have a fire hydrant sign within 100 metres of your front door. It is someВ consolation, however, that not all signage in the public domain appears stuck in a time warp. Metric Views is not qualified to comment on the problems with landing slots or passport checks, but we believe that the archaic measures on our traffic signs are an embarrassment and difficult to explain away to a visitor. Finally, on the drive into London, there are unfamiliar symbols on the traffic signs (surely вЂmвЂ™ for distance can not be metres, and what can be the meaning of quotation marks, apostrophes and вЂydsвЂ™?). Then it is necessary to queue for several hours for a passport check. First, there are delays in the air, waiting for a landing slot. We speculate what might have occurred had this job been the responsibility, not of local government, but of the UK Department for Transport (DfT), and we draw attention to a paradox.ДЄ visitor arriving from abroad could be forgiven for wondering if Britain is losing the plot. Metric Views looks at a successful but unsung project that took place during the early years of the UKвЂ™s metric transition.

Fire hydrant plan symbol