Page:UK Traffic Signs Manual - Chapter 8 - Part 2- Traffic Safety Measures and Signs for Road Works and Temporary Situations) - Operations 2009.pdf/36

OPERATIONAL ISSUES Any person, persons or organisation responsible for the works shall ensure that the site of works or the highway (or any other road to which the public have access) is left in a condition which is not dangerous to road users.

When road surfaces are removed or reshaped by planing operations before being resurfaced, the pattern of grooves left on the temporary surface and the presence of gratings and covers standing proud of the surface often create particular hazards to riders of motor cycles and bicycles.

The "TEMPORARY ROAD SURFACE" sign variant to diagram 7010.1 should be used to warn drivers of an unfinished road surface, e.g. when road surfaces are removed or reshaped by planing operations before being resurfaced. Particular attention should be given to the programming and contractual arrangements for planing and resurfacing works so as to reduce to a minimum the periods that elapse between these operations. All reasonable steps should be taken to reduce hazards in the periods when the planed lengths are used as temporary running surfaces. A longitudinal step of more than 50 mm should always be marked by a line of cones. See Part 1: Design, Section D3.18.

The "uneven road" sign to diagram 556 may be used to warn of an uneven road in those cases where traffic is required to use a carriageway with more severe undulations than those for which the "TEMPORARY ROAD SURFACE" sign variant to diagram 7010.1 would be used; see Chapter 4.

Sloping fillets formed of cold asphalt should be provided for every raised cover over which vehicles, wheelchairs, pushchairs or pedestrians may pass. They should be so sloped as to provide an easy path for vehicles, especially two-wheeled vehicles. If fillets are not provided, raised covers are a hazard both to vehicles and pedestrians. In such cases advance warning signs as described in paragraphs O3.16.4 and O3.16.5, and barriers around the obstruction together with a "keep left/right" sign to diagram 610 should be provided, augmented by warning lights during the hours of darkness.

In no case should these precautions be accepted as an alternative to the restoration of the levels of the adjacent carriageway or footway surfaces at the earliest possible opportunity.

The "RAMP AHEAD" sign variant to diagram 7010.1 warns of a sudden change of road level which the driver is approaching, and should be sited not less than 30 m before the ramp. The sign should be used when the change in level exceeds 15 mm. The sign must always be used in conjunction with the "RAMP" sign to diagram 7013. The gradient and length of the ramp will be dictated by the speed at which vehicles are expected to traverse it. Wherever possible, the ramp should be constructed at right angles to the vehicle path.

"RAMP AHEAD" and "RAMP" signs must also be used when cable crossing protectors which exceed 15 mm in height are placed in live traffic lanes. These protectors are typically to be found in use in conjunction with portable traffic signal cabling. See also Section O3.21.

The very nature of road works means that mud may be deposited on carriageways or footways and cause a hazard, but every precaution must be taken to prevent this happening. (It is an offence under the Highways Act to deposit mud or other debris onto the road surface.) Clay, chalk and similar materials become slippery when wet and therefore constitute additional dangers. All such deposits must be removed without delay. The installation and proper use of wheel washing equipment can virtually eliminate the problem. Similarly, water shall not be pumped or be allowed to flow on to the highway to an extent which may cause dangerous conditions (e.g. through the formation of ice in frosty weather). If necessary, special drainage facilities should be provided.

The "slippery road" sign to diagram 557 may be required because of the deposit on the road of mud, clay, chalk or other excavated materials. Every effort must be made to reduce this hazard to a minimum by requiring regular road washing/brushing, but the sign should be erected whenever surfaces become slippery. The provision of this sign does not absolve contractors from their duty under the. A "distance over which hazard extends" plate to diagram 570 may be used with the sign (see also Chapter 4). 34