Part 1, Regulation 3(2): The Road Vehicles (Construction and Use) Regulations 1986
overall width
the distance between longitudinal planes passing through the extreme lateral projecting points of the vehicle inclusive of all parts of the vehicle, of any receptacle which is of permanent character and accordingly strong enough for repeated use, and any fitting on, or attached to, the vehicle except—
(a) any driving mirror;
(b) any snow-plough fixed in front of the vehicle;
(c) so much of the distortion of any tyre as is caused by the weight of the vehicle;
(d) any receptacle specially designed to hold and keep secure a seal issued for the purposes of customs clearance;
(e) any lamp or reflector fitted to the vehicle in accordance with the Lighting Regulations;
(f) any sideboard which is let down while the vehicle is stationary in order to facilitate its loading or unloading;
(g) any fitting attached to part of, or to a receptacle on, a vehicle which does not increase the carrying capacity of the part or receptacle but which enables it to be
- —transferred from a road vehicle to a railway vehicle or from a railway vehicle to a road vehicle;
- —secured to a railway vehicle by a locking device; and
- —carried on a railway vehicle by the use of stanchions;
(h) any sheeting or other readily flexible means of covering or securing a load;
(i) any receptacle with an external width, measured at right angles to the longitudinal axis of the vehicle, which does not exceed 2.5 m;
(j) any empty receptacle which itself forms a load;
(k) any receptacle which contains an indivisible load of exceptional width;
(l) any receptacle manufactured before 30th October 1985, not being a maritime container (namely a container designed primarily for carriage on sea transport without an accompanying road vehicle); or
(m) any special appliance or apparatus as described in regulation 81(c) which does not itself increase the carrying capacity of the vehicle.
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I may well drive through the Rotherhithe Tunnel tomorrow.