Dennis Fallon

Reply sent via email

Ian Edwards

Speed Policy Branch

Department for Transport

Zone 2/13

Road User Safety Division

Great Minster House

76 Marsham Street

London

SW1P 4DR

Direct Line: 020 7944 2058

Fax: 020 7944 9618

GTN No: 3533 2058

Web Site: www.dft.gov.uk

30 December 2009

Dear Mr Fallon

SPEED LIMIT SIGNAGE REQUIREMENTS

Thank you for your email of 29 December concerning speed limit signing requirements. I am replying as I am responsible for speed limit policy issues.

The law relating to traffic signs is contained in The Traffic Signs Regulations and General Directions 2002 (TSRGD) and can be found at;

http://www.opsi.gov.uk/si/si2002/20023113.htm

The speed limit sign (diagram 670) is contained in Schedule 2 of TSRGD. There are seven variable sizes that a speed limit sign may be. These are; 300mm, 450mm, 600mm, 750mm, 900mm, 1200mm and 1500mm in diameter. Any speed limit sign may be any of these sizes. There are no regulations to apply a certain size sign to any particular speed limit.

However, the Department provides local traffic authorities with guidance on placing traffic signs. This guidance, the Traffic Signs Manual (TSM) can be found at;

http://www.dft.gov.uk/pgr/roads/tss/tsmanual/tsmchapter3.pdf

To answer you questions in turn;

Question 1

Table 14-1 of Chapter 3 TSM recommends that the terminal (first) speed limit signs to indicate a 40mph speed limit should be 600mm in diameter. Those signs must be placed on both sides of the carriageway.

Table 14.3 TSM recommends repeater signs should be 300mm in diameter within a 40mph speed limit.

As with the size of signs mentioned above, there are no regulations relating to exact distances between repeater signs. The law (Direction 11 TSRGD) merely states that repeater signs must be placed “at regular intervals”.

Table 14.3 TSM recommends repeater signs be no more than 500m apart on the same side of the carriageway, 350m apart on alternate sides of the carriageway and 250m between the terminal (first) signs and the first repeater sign.

Schedule 17 TSRGD requires that speed limit signs must be illuminated during the hours of darkness either by internal or external lights or using reflectorised material.

Question 2

Table 14.1 TSM recommends terminal 30mph signs should be 600mm in diameter. If the road is street lit, there will be no repeater signs as repeater signs are prohibited from street lit 30mph roads under Direction 11 TSRGD.

If there are no street lights, table 14.3 recommends repeater signs should be 300mm in diameter. The guidance goes on to suggest a maximum of 400m between repeater signs on the same side of the carriageway, 250m between signs on alternate sides of the carriageway and 200m between the terminal signs and the first repeater sign. These regulations and associated guidance remain the same irrespective of whether the limit is in place permanently or due to roadworks.

Any 40mph signs within the temporary 30mph limit should be either removed or covered. Contractors are fully aware of their duties in this respect. Obviously, once the 30mph speed limit is no longer in force, the 40mph signs should be uncovered/replaced.

Question 3

This answer is the same as at Question 2. Again, Schedule 17 TSRGD requires that speed limit signs must be illuminated during the hours of darkness either by internal or external lights or using reflectorised material.

Question 4

Motorways are subject to the same signing requirements as other roads where the speed limit is, for whatever reason, reduced. Therefore there are no legal requirements for a 40mph speed limit to be any particular size. There is no guidance in TSM as to the size of a 40mph speed limit sign on a motorway, but the recommended size of a 50mph limit is 1200mm, so traffic authorities should consider that an appropriate size.

The repeater sign and illumination requirements are identical to my answer to Question 1.

There is no requirement for a staged reduction from 70mph to 40mph, although a traffic authority may do this if they consider it appropriate. Ultimately, the size of the terminal sign (1200mm) on both sides of the carriageway, and as often on motorways, on an overhead gantry should provide drivers with sufficient time to reduce their speed. 1200mm in diameter is, after all, four feet across.

Question 5

See my answer to Question 4 above.

Question 6

This is a discretionary matter for the roadwork contractors and is impossible to provide any kind of positive response. The coned off area should stretch to however far it is necessary to ensure roadworks are completed and the safety of workers is not compromised. The repeater sign issues are resolved by Table 14-3 TSM.

To sum up, the size of speed limit signs and the frequency of repeater signs is a matter for traffic authorities. The Department provides them guidance to ensure consistency. However, failure to comply with the guidance does not, in itself, compromise the legality of any speed limit. Only a court may determine whether a traffic authority have acted correctly, based on any evidence presented to it.

I hope this is helpful.

Yours sincerely

Ian Edwards

Fallon 2