Speed Limit Sign/30 mph

The first speed limits to be introduced to the UK were the very slow 2 and 4 mph limits that came as part of the 'red flag act'. Speed limits gradually increased from 1896, until in 1930 they were abolished for all passenger vehicles capable of carrying fewer than seven people. However, in 1934 the 30 limit was reintroduced in 'built up areas'. It is presumably from this date that the first '30' signs appeared.

Pre-Worboys signs

As with so many signs, the earliest speed limit signs appear to have been simple black text on white background plates mounted on posts. However, in or around 1934 the 30 speed limit sign was introduced as a black '30' on a white background inside a red circle, much as we see today. The biggest difference and the most obvious way of spotting an old sign, is that pre-Worboys signs used a font with a flat-topped 3 figure.

Worboys Report signs

The 30 mph speed limit sign did not change enormously after the Worboys Report. The only real change was that the font was changed so that the old 'flat-topped' 3 was replaced with the more familiar rounded topped 3 that we see today.

Repeaters

In more recent years, the proliferation of repeater signs has also created 30 repeaters. Whilst illegal in street-lit built-up areas, where the surrounding road conditions are expected to inform the driver of the 30 limit, there are now many 30 limits applied to more rural settings, or Urban dual carriageways where a higher speed limit may be expected.

Backing boards

While many signs are mounted on grey back boards, another ploy used by councils to highlight speed limits is the use of large bright yellow backing boards to reduce the chance of drivers missing the signs. The back boards can come in quite a variety of shapes, widening below the 30 to enclose the village or town name plate, a simple rectangle mounted above a speed camera warning sign, or in a unit with flashing warnings of a school ahead.

Signs can also be mounted into what are effectively pieces of street furniture, if not sculpture, at the entrance to some villages.

Countdown signs

Another aid to drivers wondering what the speed limit is are countdown signs. These generally come in 3s, with 3, then 2, then 1 stripes underneath the 30 roundel. Whilst these signs normally only come in one shape, ie a tall rectangle with the '30' at the top, they feature a variety of colours. Green backgrounds with white stripes are for Primary Routes, but on non-primary local roads, the stripes can vary in colour somewhat on a white background. Yellow backing boards have also been seen, as have black stripes on a yellow background. The countdown signs have also been produced with green roundels in place of red around the '30'.

There has been some doubt as to the legality of the signs in England and Wales in the past, where they were not officially permissable. However, their widespread use suggests that the DfT was not overly concerned with their use. In Scotland, however, they were approved by Transport Scotland and so became commonplace in some council areas.

Road markings

A final help for the unsuspecting driver is the use of large speed limit roundels painted on the road surface at the entry to a 30-limit zone. These are covered in more detail in Road Markings/Speed Limit Roundels.

Irish signs

50 km/h speed limit signs on Inch Island, Co. Donegal

Before the adoption of metric speed limits, Ireland used a 30 mph speed limit sign very similar in design to that used in the UK (pre-Worboys). Today the nearest equivalent sign to the UK's 30 mph sign is the 50 km/h (31.1 mph) speed limit sign, which is used at the entrance to built-up areas.