Road under repair signs

When there is any obstruction or hole in any road or street due to repair work it shall be the duty of the Road Authority to indicate such obstruction or hole to users of the road by means of a sign or barrier, and such sign or barrier shall be lighted with a red lamp during the hours prescribed for the carrying of lights upon vehicles in motion: Provided that a sign or barrier approved by the Department of Transport for use instead of a lighted sign or barrier may be so used during such hours.