A pallet is put away from the aisle side, the forklift driver pushes it a hand's width too far, and on the other side of the back-to-back racking the opposite pallet tips into the neighbouring aisle. This scenario is why push-through protection (the backstop behind the beam) is one of the most frequently flagged items in rack inspections. It is inconspicuous, costs little and is still often forgotten, especially when a double-sided run was created later by pushing two single rows together.
This article clarifies when push-through protection is mandatory under DGUV Information 208-061, how high it has to be, when a safety clearance replaces it, and which additional safeguards are required at the rear of the racking and at rack tunnels. Rack protectors on the uprights are a separate subject, covered in the article Rack protection in the warehouse.
What happens without push-through protection
In back-to-back racking, two rows of racking stand rear to rear, connected by row spacers. Each side is loaded from its own aisle. A Euro pallet (1,200 × 800 mm) sits crosswise on two beams of a row that is usually 1,100 mm deep and overhangs by 50 mm at the front and rear. The space between the two rows, typically 200 to 300 mm, is the only reserve.
If the driver sets the pallet down too deep, it pushes the opposite load unit off its beams. A forklift can easily generate the forces needed to shift a 1,000 kg pallet. The result is not only a pallet falling into the neighbouring aisle but frequently also a damaged beam or a bent upright frame on the far side, because the pallet jams as it slides off.
The rule: 150 mm height or 100 mm safety clearance
DGUV Information 208-061 "Lagereinrichtungen und Ladungsträger" (storage equipment and load carriers; it replaced the former DGUV Regel 108-007) covers the case in sections 4.2.4.3 and 4.2.4.4:
- Section 4.2.4.3: Back-to-back racking that is loaded from both sides with non-guided handling equipment must have push-through protection that is effective up to a height of at least 150 mm.
- Section 4.2.4.4: Push-through protection is not required if, with central placement, a safety clearance of at least 100 mm is guaranteed between the largest load units placed from either side.
Three terms are decisive here. "Non-guided" means counterbalance forklifts, reach trucks and high-lift pallet trucks, i.e. all equipment that the driver positions freely. Stacker cranes and rail-guided narrow-aisle trucks are not covered. "Effective up to at least 150 mm" means that the backstop, measured from the beam, must be at least 150 mm high so that it reliably stops a pallet including its blocks. And "with central placement between the largest load units" means that the clearance is measured not between the rack frames but between the two load units when both sit correctly centred on their beams, using the largest load unit that occurs there.
Worked example
Two rows with 1,100 mm deep frames, row spacers of 250 mm, Euro pallets placed crosswise with a depth of 1,200 mm:
- Rear overhang of each pallet with central placement: (1,200 − 1,100) / 2 = 50 mm
- Clearance between the two load units: 250 − 50 − 50 = 150 mm
- Result: 150 mm ≥ 100 mm, so push-through protection is not mandatory under 4.2.4.4.
The same racking with 200 mm row spacers yields only 100 mm, i.e. exactly the limit value. And as soon as industrial pallets with a depth of 1,200 mm placed lengthwise, or load units with overhang (cardboard, film, protruding goods) come into play, the clearance is used up. In practice, push-through protection is therefore recommended for every back-to-back run with a row spacing of less than 300 mm, regardless of whether the calculation still just yields 100 mm. It also protects against the everyday reality that pallets are not always placed exactly in the centre.
Rear side and rack tunnels: what else must be secured
Push-through protection is only one of several safeguards against falling goods that the same section of DGUV Information 208-061 requires:
- Sides not intended for loading (4.2.4.1): The rear of a single-sided rack adjacent to a traffic route, a workplace or a wall set at a distance must be secured against load units and goods falling off. The sizing depends on the dimensions and loads of the load units. Usual solution: rear mesh panels or mesh back cladding, with a finer mesh for loose goods.
- Areas above rack tunnels (4.2.4.2): Where people walk or forklifts drive through beneath the racking, the levels above must be designed so that goods cannot fall down or through, for instance with grating decks, support meshes and side fall guards. Tunnels intended for that purpose also count as traffic routes (section 4.1.4) subject to the requirements of ASR A1.8.
- Supports for load units (4.2.3.2): Depth support bars, pallet supports and drum supports must be designed and arranged so that they cannot fall off and can safely carry the load units. Anyone storing mesh boxes or special pallets checks the supports as well.
- Beam locking (4.2.3.3): On racking served by forklifts, the beams must be secured against an uplift force of at least 5,000 N. Missing beam locking pins are the second most common defect after missing push-through protection.
Calculator: do I need push-through protection?
Four figures and one line of mental arithmetic are enough:
| Step | Value | Example |
|---|---|---|
| 1. Frame depth of the rack row | T | 1,100 mm |
| 2. Depth of the largest load unit (in the direction of placement) | L | 1,200 mm |
| 3. Clear distance between the two rack rows (row spacer) | A | 250 mm |
| 4. Safety clearance with central placement | S = A − (L − T) | 250 − 100 = 150 mm |
If S is less than 100 mm, push-through protection is mandatory under DGUV Information 208-061. If S is between 100 and 150 mm, it is strongly recommended, because every pallet not placed centrally uses up the clearance. For load units with overhang, calculate with the actual depth of the goods, not the pallet.
Designs compared
| Solution | Effect | Suitable for | Points to note |
|---|---|---|---|
| Push-through protection (stop angle or tube behind the beam) | stops the pallet mechanically, effective to at least 150 mm | back-to-back racking served by forklifts | match the distance to the beam to the pallet overhang; do not misuse as a rack protector |
| Rear mesh panel | retains load units and loose goods | single-sided racking along routes, workplaces, walls | mesh size according to the goods; height at least up to the top edge of the highest load unit |
| Depth support bars / pallet supports | secure support for mesh boxes, special pallets, drums | mixed load units | must be secured against falling off (4.2.3.2) |
| Grating or steel panel decks | prevent goods falling through | levels above tunnels, small parts on pallets | observe the shelf load of the deck, adjust the load notice |
Suitable accessories for all four solutions can be found under pallet racking accessories; rack protectors for uprights and rack corners under rack protection.
Retrofitting: what matters
Push-through protection can be retrofitted to almost any pallet racking, because it is fixed to the beams or to the upright frame. Five points determine a clean retrofit:
- System compatibility: Beam and frame profiles differ from manufacturer to manufacturer. Clamp-on or plug-in adapters must fit the profile; universal angles are bolted to the frame.
- Position: The backstop sits far enough behind the beam that a centrally placed pallet does not touch it, while a pallet pushed too deep hits it immediately. With a 50 mm pallet overhang, 75 to 100 mm behind the rear edge of the beam works well.
- Height: Top edge at least 150 mm above the top of the beam (4.2.4.3). Set it higher for load units with tall blocks or skids.
- Modify only when unloaded: Under section 5.2.1.1, racking may only be modified when unloaded and in accordance with the assembly and operating instructions. This also applies to retrofitted safeguards if beams have to be moved for them.
- Load notice: If the retrofit changes nothing about beam spacing or bay widths, the notice remains valid. Anyone who moves beams at the same time must have it reassessed (see reading the load notice correctly).
Push-through protection is not a crash barrier. It is meant to stop a slowly pushed pallet, not to catch a forklift. Anyone using it for that purpose damages beams and frames.
Frequently asked questions
Does the requirement also apply with a 300 mm row spacing?
Do the arithmetic: with 1,100 mm frames, 1,200 mm pallets and a 300 mm spacing, 200 mm of safety clearance remains with central placement. That satisfies section 4.2.4.4, so push-through protection is not prescribed in that case. It remains advisable if load units overhang or drivers regularly set pallets down too deep. The rack inspection shows this in scratch marks on the beams.
Must back-to-back racking loaded from one side only be secured?
If loading takes place from one side only and the other side is not accessible, 4.2.4.3 does not apply. Section 4.2.4.1 then applies instead: the side not intended for loading must be secured against goods falling off as soon as a traffic route, a workplace or an area where people are present lies behind it. In practice, this likewise comes down to push-through protection or a rear mesh panel.
Do shelving or wide-span racks need push-through protection?
Not under 4.2.4.3, because they are loaded by hand and not with handling equipment. A hand-loaded double-sided rack holding goods that can be pushed through to the rear should nevertheless have a back panel or a stop; this follows from the general obligation in section 5.1.3 to load storage equipment so that goods cannot fall out or down.
What does the rack inspector check on the push-through protection?
Presence in every bay of back-to-back racking served by forklifts, effective height, firm fixing, deformation and impact marks. A bent backstop indicates that pallets are regularly set down too deep, and thus also points to beam damage. How findings are rated under the traffic-light system is explained in damage classes according to DIN EN 15635. Our rack inspection includes the safeguards against falling goods in every inspection scope.
Sources
- DGUV Information 208-061 „Lagereinrichtungen und Ladungsträger", edition November 2023, updated version July 2024 (sections 4.1.4, 4.2.3, 4.2.4, 4.2.5, 5.1.3, 5.2.1)
- DGUV Information 208-043 „Sicherheit von Regalen", edition June 2020
- DIN EN 15635:2009-08 „Ortsfeste Regalsysteme aus Stahl – Anwendung und Wartung von Lagereinrichtungen"
- DIN EN 15620:2021-11 „Ortsfeste Regalsysteme aus Stahl – Grenzabweichungen, Verformungen und Freiräume"
- DIN EN 15512:2021-06 „Ortsfeste Regalsysteme aus Stahl – Verstellbare Palettenregale – Grundlagen der statischen Bemessung"
- ASR A1.8 „Verkehrswege"