obtain further information about road works,  see Conversions and further reading.  Law RTRA sect 16  2.Additional rules for  high-speed roads  289. Take special care on motorways and other high-speed dual  carriageways.  ● One or more lanes may be closed to traffic and a lower  speed limit may apply.  ● Works vehicles that are slow moving or stationary with a  large ‘Keep Left’ or ‘Keep Right’ sign on the back are  sometimes used to close lanes for repairs, and a flashing  light arrow may also be used to make the works vehicle  more conspicuous from a distance and give earlier warning  to drivers that they need to move over to the next lane.  ● Check mirrors, slow down and change lanes if necessary.  ● Keep a safe distance from the vehicle in front (see Rule 126).  290. Contraflow systems mean that you may be travelling in a  narrower lane than normal and with no permanent barrier  between you and oncoming traffic. The hard shoulder may be used  for traffic, but be aware that there may be broken-down vehicles  ahead of you. Keep a good distance from the vehicle ahead and  observe any temporary speed limits.  highwaycodeuk.co.uk 148 