Sentido de Vida

O10.6.1 General works vehicle issues are dealt with in Section O5. This section relates specifi cally to MLC vehicles.

O10.6.2 The block vehicles used to form the closure in live traffi c lanes should be as specifi ed for an Impact Protection Vehicle in paragraph O5.5.5 except that signing shall be in accordance with the relevant parts of

Section O10.7 below.

O10.6.3 All vehicles and trailers should be fi tted with a roof-mounted amber warning light bar (comprising at least two independent light sources) or two independent roof-mounted fl ashing amber warning beacons, visible through 360° whether the sign display board is displayed or in the transport position. It is important that the rotating beacons are visible to oncoming drivers when the signs are being erected or folded. Subject to the requirements of paragraph O10.1.10, rotating beacons on block vehicles that are visible to the rear should not be used when the light arrow sign or four rear-mounted amber lanterns are in operation. Beacons shall comply with Section O5.3.

O10.6.4 Block vehicles ideally should be loaded to have an on-the-road weight of between 10 and 15 tonnes. The block vehicle should not have an on-the-road weight of less than 10 tonnes. The choice of block vehicles should refl ect the acceleration and manoeuvrability required of them by the method of working.

O10.6.5 In view of the very low speeds at which some of these operations are undertaken, it may be advantageous to select vehicles with an appropriate low ratio drive.

O10.6.6 To minimise the risk of vehicles cutting in between the working vehicle and the block vehicle, a sign to diagram 7403 should be fi tted to the rear of the working vehicle or be trailer-mounted and towed by the working vehicle. If these two options are not practicable, then the working vehicle should carry a “keep left/ right” sign to diagram 610 with a diameter of 1500 mm.

O10.6.7 The number of working vehicles may be varied according to the nature of the work being undertaken. Unless it is not practicable to do so, a sign to diagram 7403 should be fi tted to the rear of each working vehicle or be trailer-mounted and towed by the working vehicle. See paragraph O10.7.5.

O10.6.8 Personnel may experience diffi culty reading marker posts at night so the fi tting of an adjustable spotlight is advised. Before leaving the depot all lighting equipment should be checked.

O10.6.9 When working vehicles or personnel are operating on the hard shoulder a block vehicle with a LMCC is required. The working vehicles should carry a “keep right” sign to diagram 610, which should be 1500 mm diameter unless this is not practicable in which case the largest possible sign should be used. The block vehicle on the hard shoulder should carry a sign to diagram 7403 or the recommended alternative light arrow sign. See Section O10.8 below. The light arrow sign shall not display any form of arrow when on a two- way single carriageway road and, other than at the scene of an incident, the light arrow sign shall not display any form of arrow when on a hard shoulder of a dual carriageway. If the works vehicle carrying the sign to diagram 7403 (or the higher visibility alternative) is substantial (e.g. a gully emptier or sweeper) and is fi tted with a LMCC, the block vehicle may be dispensed with.

O10.6.10 Regulation 14 gives details of the signs that may be attached to vehicles. The light arrow sign is not listed in regulation 14 and so needs separate signs authorisation and type approval from the appropriate Secretary of State.

O10.7 SIGNS

O10.7.1 Signs on the carriageway should always be vehicle or trailer-mounted and attended at all times. Signs on the verge may be vehicle or trailer-mounted or static and need not be attended.

O10.7.2 All traffi c signs used in connection with this technique must comply with the relevant requirements of the Traffi c Signs Regulations and General Directions 2002 (TSRGD), the Lighting Regulations and BS EN 12899-1:2007 “Fixed, vertical road traffi c signs” and BS 8408:2005 “Road traffi c signs. Testing and performance of microprismatic retrorefl ective sheeting materials. Specifi cation”.

O10.7.3 The sign prescribed for use with the advance sign vehicles is diagram 7402 using 300 mm wide arrows; see working drawing P7202 for design details. Working drawings for the design of the signs shown in the plans and other prescribed signs are available for download free of charge from the Department for Transport website: www.dft.gov.uk/roads/signs.

O10.7.4 The MLC signs to diagrams 7402 and 7403 must be refl ectorised in their entirety, including the yellow background in which the fl ashing amber lamps are installed. The material, when rated in accordance with BS 8408 “Testing and Performance of microprismatic retrorefl ective sheeting – Specifi cation” shall have a performance index of not less than 3.0 for a V1 vehicle (passenger car), using angularity A1, luminance index B and a sign location correction factor of 1.0. It shall achieve this performance index rating for each of the distance ranges D1, D2 and D3. It is not necessary to provide sign lighting luminaires when signs are refl ectorised in accordance with this specifi cation (except in Northern Ireland). Care and maintenance of the sheeting material should be in accordance with the manufacturer’s guidelines. See also Section O4.3.

O10.7.5 The sign to diagram 7403 may be used with the block vehicle, but a higher visibility light arrow alternative sign is recommended. This sign incorporates a fl ashing light arrow to supplement the message given by the “keep left/right” sign to diagram 610. The design and operation of the sign must have type approval and special signs authorisation. A description of this sign is given in SectionO10.8. The light arrow sign shall not display any form of arrow when on a two-way single carriageway road and, other than at the scene of an incident, the light arrow sign shall not display any form of arrow when on a hard shoulder of a dual carriageway.

O10.7.6 On the light arrow sign and the sign to diagram 7403, the arrow on the “keep left/right” sign to diagram 610 must be capable of indicating either “keep left” or “keep right”. To avoid displaying an incorrect instruction during set up and removal of the MLC, the rotation of the arrow, or covering of the sign, should be carried out remotely from the driver’s cab, with a means for the driver to verify the arrow direction or state of the sign.

MOBILE LANE CLOSURE TECHNIQUE

O10.7.7 Adequate means should be provided to support the sign display boards, bearing in mind the possible operating speeds. The lower edge of every sign display board when mounted on a vehicle should be at least 0.75 m above the road surface. When fi tting a sign display board to a vehicle, the vehicle’s rear lights, refl ectors and number plate must not be obscured.

O10.7.8 Signs shall be removed from the view of following drivers when not in use. If a blind is used it should be opaque and preferably yellow, and should fully reveal or fully cover the sign. When visible to other road users, the “keep left/right” sign must not be rotated to a vertical position.

O10.7.9 Flap type variable message signs should be constructed to facilitate opening/closing by a person standing in a safe position. They should be fi tted with a means of securing them in both the open and closed positions. The construction and colouring of these signs should be such that the appearance of the sign is not compromised regardless of whether the fl aps are up or down. Particular attention should be given to the fl ap hinge detail in this respect.

O10.7.10 On lane closure signs, each arrow symbol should be capable of being fl apped to show a red bar symbol as an alternative to the arrow. Each fl ap should be fi tted with a means of securing it in either of these positions. The red bars must be at the correct height otherwise the legibility of the lane closed symbol is affected, especially at night, making it diffi cult to distinguish between open and closed lanes. The correct confi guration for the fl aps is detailed on working drawing P7402.

O10.7.11 Signs should not be manually changed when the sign vehicle is standing on a live traffi c lane.