U13 Temporary Sign – Speed Limit 50 km/h, Ø80 cm, Class II

U13 Temporary Sign – Speed Limit 50 km/h, Ø80 cm, Class II

The 50 km/h limit for work zones, on an Ø80 cm yellow disc with class II prismatic sheeting. On national roads outside built-up areas, where traffic moves much faster, it is often the first step down in speed before the site.

Why class II

Class II (RA2) prismatic sheeting shows up three to four times better at night than class I sheeting, even among plant lights and street lights. For temporary signing, SR 1848-2 adds a clear rule: a temporary sign must have at least the retroreflection class of the permanent signs on the section, so on roads already signed in class II it is the compliant choice.

Where it goes, under SR 1848-1:2024

It limits speed to 50 km/h on the work section; its permanent counterpart is the C27. The value is chosen to suit the conditions in the work zone, and the end of the limit is shown with the U14 (End of all restrictions); in class II, the U14_II. SR 1848-1:2024 sets no specific distance for this sign: it is installed under the technical regulations in force for signing roadworks, following the signing layout of the works. 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.

If permanent signs on the section contradict the temporary signing, for example a different speed limit, the rules require them to be removed or covered with a mask for as long as the restriction lasts.

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

• 80 cm diameter yellow disc, red border, with the number 50;
• 1 mm galvanised steel sheet, with pressed edges, no sharp edges;
• electrostatically painted;
• class II (RA2) prismatic retroreflective sheeting, with a guaranteed 10-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.

Like all temporary signs that have a permanent counterpart, it has the same symbols and sizes, but the white background is replaced with yellow (SR 1848-2), so drivers recognise roadworks signing at once. As with permanent signs, the Ø80 cm disc is the large format in SR 1848-2, required on national roads; motorways use Ø100 cm, and other roads and streets Ø60 cm. The Ø60 cm version with class I sheeting is the U13-50.