This is a complex subject and the best explanation of it is given by VOSA so here is an extract of it.
NOTE 1: Where the rear of a bumper is 'contactable' this criteria will apply.
NOTE 2: The assessment of a registration plate mounting bracket should take account of the likely position of a registration plate. A dummy registration plate may be used to assess contactable parts of a bracket against the requirements.
b. Check all hard parts on or protruding by 5mm or more from the external surface, which are contactable with a 100mm dia. sphere, and which are exempt by "Application item b" are blunted.
NOTE 3: The checks at 'a' and 'b: must be carried out with the steered wheels in the
"straight ahead" position only. Exposed steering, suspension or brake components, eg on vehicles fitted with "cycle wing" mudguards. must be checked from the front only. Components contained within the inner wheel "dish", eg brake disc, stub axle assembly, are not subject to this criteria.
NOTE 4: Items not normally employed for the specific purpose by a major manufacturer eg a temporary fixing or covering, should not be considered acceptable. Materials, methods and application used in rectification may be accepted if they are permanent, durable and are of a kind which would normally be used by a major manufacturer. In the case of exposed steering/suspension components it will be acceptable to use a "hard" rubber/plastic capping device to cover otherwise exposed threaded fasteners or hard rubber/plastic covering on a threaded steering shaft providing it cannot be easily removed and it complies with the Exterior Projection requirements.
NOTE 5: The approval of a lamp (as indicated by the 'e' or 'E' marking) only relates to the performance characteristics of the lamp and does not confirm compliance in respect of Exterior Projections.
NOTE 6: The criteria of item 2a does not apply to folds in body panels or to the following items, which must be checked to their individual requirements.
3. Check:
a. protrusions of less than 5mm, but of more than 1.5mm, are blunted.
b. grills'gaps (eg air intakes or outlets including that part of a grill that projects over the surface of the body and the cooling fins of air cooled engines) having gaps of • more than 25mm but not more than 40mm have edges with a radius of curvature of not less than 1mm on any external surface
• more than 10mm but not more than 25mm have edges with a radius of curvature of not less than 0.5mm on any external surface
• not more than 10mm have edges which are blunted.
NOTE: The width of a gap/grill is measured between the contact points of a 100mm dia sphere bridging the gap/grill.
e. windscreen, headlamp and rear window wiper blades and their supports are blunted.
d. wheels, wheel nuts, hub caps or wheel discs do not have any pointed or sharp features (ie all edges must be blunted) which project beyond the external plane of the wheel rim.
e. wheels
• which must not be fitted with any wing nut • which, above the horizontal, plane passing through the axis of rotation, must not project beyond the vehicle body plan form (other than in the case of tyres, wheel discs and central wheel securing nuts)
• on which any wheel disc or central wheel securing nut that projects beyond the
vehicle body plan form does not have a radius of curvature of less than 30mm and
does not project more than 30mm.
f. sheet metal edges, are folded back on themselves byapprox 180°.
g. lateral air or rain deflectors, where any edge capable of being directed outwards
requires a radius of curvature of not less than 1mm.
h. fixing holes and recesses less than 12mm diameter have a blunted edge.
I. aerial shafts, which must be fitted with a fixed capping having a radius of curvature of not less than 2.5mm.
j. hard parts made of plastic or rubber which are flexible have a blunted edge.
k. FRP (Fibre Reinforced Plastic) panel edges have a radius of curvature of not less than 1.5mm.
IN ADDITION to the criteria applicable at Item
4. Check
a. bumpers, that the ends are turned inwards or recessed (integrated) within the bodywork
b. handles, hinges and push buttons on doors, luggage compartments, bonnets, covers etc and fuel tank filler caps
i. do not project from the external surface more than
• 50mm where they cannot under any circumstances project beyond the extreme outer edge of the vehicle
• 40mm in all other cases.
c. all handles
i. which rotate parallel to the plane of the door are turned in towards the door.
ii. that the open end of any handle that rotates parallel to the plane of the door
• is directed rearwards, or
• if under no circumstances the handle projects beyond the extreme outer edge
of the vehicle, either
- the open end is shielded to the front by a protective surround the open end is recessed into the vehicle bodywork
- the gap measured laterally between the open end of the handle and the vehicle body is not more than 2mm (with the handle in its normal position and the door latched).
iii. that pivot outwards have the open end facing either rearwards or downwards unless
• they have an independent return mechanism, and
• should the return mechanism fail they will not project more than 15mm.
d. windows opening outwards from the external surface of the vehicle; that under all conditions of use
• have no forward facing exposed edges
• do not project beyond the extreme outer edge of the vehicle.
NOTE: The requirements of item 'd' do not apply to a window fitted to a Motor Ambulance or a Motor Caravan which is fitted to the rear of the drivers seat, and
• in the case of a Motor Ambulance, is in the medical working area
• in the case of a Motor Caravan, is in the living area.
e. headlight visors and rims do not project more than 30mm beyond the lens surface (measured horizontally from the point of contact of 100mm dia sphere touching lens and visor rim).
f. jacking brackets do not project beyond the floor line lying directly above them by more than 10mm.
g. exhaust pipes where the tailpipe projects beyond the floor line lying directly above it by more than 10mm terminate in a radius of curvature of not less than 2.5mm.
NOTE 2: The assessment of a registration plate mounting bracket should take account of the likely position of a registration plate. A dummy registration plate may be used to assess contactable parts of a bracket against the requirements.
b. Check all hard parts on or protruding by 5mm or more from the external surface, which are contactable with a 100mm dia. sphere, and which are exempt by "Application item b" are blunted.
NOTE 3: The checks at 'a' and 'b: must be carried out with the steered wheels in the
"straight ahead" position only. Exposed steering, suspension or brake components, eg on vehicles fitted with "cycle wing" mudguards. must be checked from the front only. Components contained within the inner wheel "dish", eg brake disc, stub axle assembly, are not subject to this criteria.
NOTE 4: Items not normally employed for the specific purpose by a major manufacturer eg a temporary fixing or covering, should not be considered acceptable. Materials, methods and application used in rectification may be accepted if they are permanent, durable and are of a kind which would normally be used by a major manufacturer. In the case of exposed steering/suspension components it will be acceptable to use a "hard" rubber/plastic capping device to cover otherwise exposed threaded fasteners or hard rubber/plastic covering on a threaded steering shaft providing it cannot be easily removed and it complies with the Exterior Projection requirements.
NOTE 5: The approval of a lamp (as indicated by the 'e' or 'E' marking) only relates to the performance characteristics of the lamp and does not confirm compliance in respect of Exterior Projections.
NOTE 6: The criteria of item 2a does not apply to folds in body panels or to the following items, which must be checked to their individual requirements.
3. Check:
a. protrusions of less than 5mm, but of more than 1.5mm, are blunted.
b. grills'gaps (eg air intakes or outlets including that part of a grill that projects over the surface of the body and the cooling fins of air cooled engines) having gaps of • more than 25mm but not more than 40mm have edges with a radius of curvature of not less than 1mm on any external surface
• more than 10mm but not more than 25mm have edges with a radius of curvature of not less than 0.5mm on any external surface
• not more than 10mm have edges which are blunted.
NOTE: The width of a gap/grill is measured between the contact points of a 100mm dia sphere bridging the gap/grill.
e. windscreen, headlamp and rear window wiper blades and their supports are blunted.
d. wheels, wheel nuts, hub caps or wheel discs do not have any pointed or sharp features (ie all edges must be blunted) which project beyond the external plane of the wheel rim.
e. wheels
• which must not be fitted with any wing nut • which, above the horizontal, plane passing through the axis of rotation, must not project beyond the vehicle body plan form (other than in the case of tyres, wheel discs and central wheel securing nuts)
• on which any wheel disc or central wheel securing nut that projects beyond the
vehicle body plan form does not have a radius of curvature of less than 30mm and
does not project more than 30mm.
f. sheet metal edges, are folded back on themselves byapprox 180°.
g. lateral air or rain deflectors, where any edge capable of being directed outwards
requires a radius of curvature of not less than 1mm.
h. fixing holes and recesses less than 12mm diameter have a blunted edge.
I. aerial shafts, which must be fitted with a fixed capping having a radius of curvature of not less than 2.5mm.
j. hard parts made of plastic or rubber which are flexible have a blunted edge.
k. FRP (Fibre Reinforced Plastic) panel edges have a radius of curvature of not less than 1.5mm.
IN ADDITION to the criteria applicable at Item
4. Check
a. bumpers, that the ends are turned inwards or recessed (integrated) within the bodywork
b. handles, hinges and push buttons on doors, luggage compartments, bonnets, covers etc and fuel tank filler caps
i. do not project from the external surface more than
• 50mm where they cannot under any circumstances project beyond the extreme outer edge of the vehicle
• 40mm in all other cases.
c. all handles
i. which rotate parallel to the plane of the door are turned in towards the door.
ii. that the open end of any handle that rotates parallel to the plane of the door
• is directed rearwards, or
• if under no circumstances the handle projects beyond the extreme outer edge
of the vehicle, either
- the open end is shielded to the front by a protective surround the open end is recessed into the vehicle bodywork
- the gap measured laterally between the open end of the handle and the vehicle body is not more than 2mm (with the handle in its normal position and the door latched).
iii. that pivot outwards have the open end facing either rearwards or downwards unless
• they have an independent return mechanism, and
• should the return mechanism fail they will not project more than 15mm.
d. windows opening outwards from the external surface of the vehicle; that under all conditions of use
• have no forward facing exposed edges
• do not project beyond the extreme outer edge of the vehicle.
NOTE: The requirements of item 'd' do not apply to a window fitted to a Motor Ambulance or a Motor Caravan which is fitted to the rear of the drivers seat, and
• in the case of a Motor Ambulance, is in the medical working area
• in the case of a Motor Caravan, is in the living area.
e. headlight visors and rims do not project more than 30mm beyond the lens surface (measured horizontally from the point of contact of 100mm dia sphere touching lens and visor rim).
f. jacking brackets do not project beyond the floor line lying directly above them by more than 10mm.
g. exhaust pipes where the tailpipe projects beyond the floor line lying directly above it by more than 10mm terminate in a radius of curvature of not less than 2.5mm.