U39 Temporary Sign – Road Accident, 70 cm, Class I

U39 Temporary Sign – Road Accident, 70 cm, Class I

The 70 cm yellow triangle warning of an accident ahead, with class I retroreflective sheeting. It is the sign used by police crews and the services that attend road incidents.

When class I is used

The class I version is the economical choice for work sites on local roads: RA1 retroreflective sheeting with a 7-year service life. The SR 1848-2 rule is simple: a temporary sign must have at least the class of the existing signing on the section, and areas with many light sources call for prismatic class 2 or 3 sheeting.

Where it goes, under SR 1848-1:2024

It is installed on the approach to the scene of a road incident that involves a temporary traffic restriction. SR 1848-1:2024 states that it is installed by the traffic police. Like any sign, it normally goes on the right-hand side of the direction of travel, so that it can be seen from at least 50 m in built-up areas and at least 100 m outside them (SR 1848-2).

What the roadworks rules require (Order 1112/411/2000)

The sign belongs to the advance signing, which is installed first, ahead of the work zone in the direction of travel, with at least 50 cm of clear space outside the carriageway. The rules require signs to be stood on the ground first, to check that they are clearly visible, and only then fixed to a support; no more than two signs go on the same support or side by side, and on one-way roads or bends they can be repeated on the left side or above the road.

On public roads, works are signed under the methodological rules approved by Order MI/MT no. 1112/411/2000. The road closure or traffic restriction is approved by the road authority, with the traffic police's agreement, on the basis of a signing layout endorsed as final, a copy of which the contractor keeps at the work site. The contractor installs, completes and maintains the signing for the whole job, removes it at the end and restores the original signing; accidents caused by incomplete or missing temporary signing are entirely the contractor's responsibility.

At night, if the existing signing on the road is retroreflective, the temporary signing must be retroreflective too and can be supplemented with flashing or sequential (“cascade”) amber lamps; on main and connecting streets in towns, retroreflective temporary signs are supplemented with flashing amber lamps.

Technical data

• triangle with a 70 cm side, red border and yellow background, with the two-crashed-vehicles symbol;
• 1 mm galvanised steel sheet, with rounded corners and pressed edges, no sharp edges;
• electrostatically painted;
• class I retroreflective sheeting (RA1), with a 7-year service life;
• fixings included: 2 clamps for Ø48 mm posts and 4 bolts with nuts;
• compliant with SR EN 12899-1:2007, SR 1848-1:2024, SR 1848-2:2011 and SR 1848-3:2011.

Mounting and size

Fixings for the post are included: 2 clamps for Ø48 mm posts and 4 bolts with nuts; clamps for Ø60 mm posts are available on request. The bottom edge of the sign goes 1.50–2.50 m above the road or kerb, and the edge nearest the road 0.50–2.0 m from the road platform. Temporary signs can also be mounted on mobile supports (SR 1848-2), such as the V2-15 or V2-28.

As with permanent signs, the 70 cm triangle is the normal format in SR 1848-2, for county and local roads, streets and private roads open to public traffic; national roads call for the large 90 cm format.