The use of steel spiked chocks is recommended for wheeled vehicles of more than 10 t.
When vehicles cannot be immobilized by applying the hand brake or by engaging the transmission in
first gear (inoperative vehicles).
Only for vehicles of more than 1500 kg, 25 for trailers and semi-trailers with one axle, whatever their
If, for any reason, a wagon is detached from a block train, its load must be secured in accordance
with Type I or Type II conditions for individual wagons before onward routing.
Wedging timber 50 x 100 x 500 mm.
Change 4 AA-23