Between the wheels of a truck or trailer is a gap that can pull a cyclist or pedestrian under the vehicle in a side-impact collision. Lateral protection devices - sideguards - exist to close that gap, and they are among the most quietly life-saving pieces of equipment regulation ever imposed on heavy vehicles. They are also among the most neglected: bent, corroded, missing sections, or defeated by aftermarket equipment mounted in the wrong place.
DVSA’s own guidance states the purpose plainly: the lateral protection device is there to help reduce the likelihood of injury to unprotected road users when struck by a vehicle travelling in a forward direction. The phrase matters - unprotected road users means cyclists, pedestrians, motorcyclists: the people who, in a sideswipe or a turning incident, would otherwise enter the space under the vehicle’s body and ahead of the rear wheels. Sideguard requirements are a direct response to the mechanics of how trucks kill vulnerable road users, which is why urban safety schemes have spent a decade tightening around exactly this area.
The approval standard is not decorative: DVSA will check that lateral protection devices do what they are intended to do and that they meet the required standards of section 42 (lateral protection) of the IVA inspection manual. The manual sets the dimensional and strength requirements - the guard must present a continuous outer surface, resist specified forces, and cover the required zone between axles.
The geometry rules are precise enough to check with a tape measure, and two of them catch more vehicles than any others. Where the cab is narrower than the body, the leading edge of the lateral protection must be within 100mm of the cab - and the device may be turned or angled in toward the cab by no more than 45 degrees to meet that standard. The same 100mm figure governs the lateral gap: the protective barrier has to sit close enough to the bodywork that a person cannot pass through the space it is meant to close. Gaps beyond the permitted dimensions are non-compliance, whatever the guard looks like from across the yard.
Walk any industrial estate and the same defects repeat. Sections missing where a bodybuilder mounted toolboxes, cranes or tanks and never reinstated the guard. Guards bent inward from kerb strikes, opening the very gap the regulation closes. Corrosion at the mounting brackets that leaves the bar hanging by habit rather than attachment. Guards removed for a repair and not refitted. And on older vehicles, improvised bars that were never a compliant device at all - a length of scaffold tube may look the part and meet none of the dimensional or strength requirements.
Each of these is an MOT failure and a roadside prohibition candidate, but the more important framing is the original purpose: a vehicle with a defeated sideguard has lost the protection that decides whether a cyclist sideswiped in traffic goes under the wheels or bounces off the bar. Urban fleets - construction, waste, distribution - run every day in the exact environment sideguards exist for.
Sideguards belong in the inspection system like any other safety component. The daily walkaround catches the obvious - a section hanging or missing. The safety inspection should check presence, security, condition and the dimensional basics against the manual: is the guard complete along the required zone, firmly attached, and within the gap limits at the cab and the body? Any bodywork change - new toolbox, crane refit, tank installation - should trigger a specific sideguard review, because the workshop that fitted the equipment was thinking about the equipment, not the guard.
Lateral protection exists for the road user who never sees the truck that hits them. The standards are measurable - section 42 of the IVA manual, the 100mm rules at cab and body, the 45-degree angle limit - and DVSA checks them at approval, at annual test and at the roadside. A complete, secure, correctly dimensioned sideguard is cheap to keep and occasionally fatal to lose. Treat it as safety equipment, not bodywork trim, and the inspections take care of themselves.
The compliance floor is only the start of where urban safety is heading. City schemes and fleet standards increasingly push past the basic lateral protection requirement toward additional protection - improved underrun geometry, side sensors and cameras, direct-vision cabs that let the driver see the risk rather than infer it. Operators tendering for urban work - construction logistics in London above all - already find sideguard condition and supplementary safety kit written into contract audits. The fleets that treat the IVA standard as a starting point rather than a ceiling are the ones whose vehicles keep working as city access rules tighten; the ones running bent bars and missing sections are accumulating a problem that arrives as a failed audit, not a warning.