Lane Closure Arrow Sign
The TC-4 sign must be used to inform road users to merge into an adjacent open lane or on a partial lane shift.
900 mm x 900 mm (standard)
750 mm x 750 mm - truck-mounted TC-4 may be used for SD work operations where the normal
posted speed is 60 km/h or lower.
1200 mm x 1200 mm (oversized) - must be used on roadways with more than two lanes for long duration
operations and posted speeds of 70 km/h or higher. In urban areas, the standard size sign
may be used if space does not permit the oversized sign.
1200 mm x 1200 mm (oversized) - must be used on freeways.