Industrial aluminium walkways fail for three reasons, and corrosion of the aluminium itself is rarely one of them. They fail because the deck was specified at a slip rating that suits a dry factory floor rather than an oily one, or because the load class was copied from a pedestrian bridge rather than calculated for operatives carrying equipment. The third reason is a stainless fixing bolted straight into aluminium next to salt water, where the joint corrodes long before the structure does.
All three are specification problems rather than material problems, which means all three are avoidable at the drawing stage. This article covers what to write down.
Slip resistance: what R12 means and when it is not enough
Slip ratings for industrial flooring in Europe come from DIN 51130, which measures the angle at which a person walking on an oiled surface begins to slip. The scale runs from R9 at the shallow end to R13, and each step up represents a meaningfully steeper safe angle rather than a marketing gradation.
R12 is the sensible default for industrial access structures and it is what we supply as standard. It covers walkways in plants where the surface gets wet, where operatives work in heavy footwear, and where occasional oil or product spillage is foreseeable rather than continuous.
Where R12 stops being enough is in areas of sustained grease or oil contamination, and in food processing zones handling fats. Those environments call for R13, and the specification should say so explicitly, because a supplier quoting to a generic anti-slip requirement will price the lower rating. There is a second axis that specifications almost always omit: displacement space, graded V4 to V10, which describes how much contaminant the surface profile can hold before it stops working. In a wash-down environment the displacement value often matters more than the R number.
Where aluminium actually needs care
Aluminium does not rust, and in most industrial atmospheres it outlasts painted steel by a wide margin because the oxide layer reforms itself wherever the surface is damaged. That is the reason it works in ports, on fish farms and over treatment tanks without a repainting programme. It is also the reason most published material on the subject stops there, which leaves specifiers unaware of the two conditions that do require attention.
The first is galvanic contact. Aluminium sitting against stainless steel, carbon steel or copper alloys in the presence of an electrolyte forms a cell, and the aluminium is the one that corrodes. In a dry indoor plant this is academic. On a quayside, over a saltwater pen or in a wash-down bay it is the single most likely place for a structure to deteriorate, and it happens at the fixings and bearing points rather than across the deck. The remedy is ordinary engineering practice: isolating washers and bushes, correctly specified fastener materials, and bearing details that separate the metals. It just has to be in the specification.
The second condition is pH, because the protective oxide layer is stable across the normal range but is attacked by strong alkalis and strong acids. Most industrial cleaning regimes sit comfortably inside the safe band, but caustic wash-downs do not, and a food or chemical facility should state its cleaning chemistry in the enquiry rather than after handover.
Neither point argues against aluminium. Both argue for saying what the environment is, because a structure detailed for a dry warehouse and a structure detailed for a saltwater quayside are not the same structure even when the span and the deck width match.
Load class: why the pedestrian figure is the wrong starting point
Public footbridges are commonly designed to a uniformly distributed load of 5 kN/m². Copying that figure into an industrial specification looks conservative and often is not, because the governing case in a plant is rarely a crowd.
It is usually a concentrated load: a maintenance technician with a toolkit, a drum on a trolley, a pallet truck crossing an inter-building link, or a small item of plant being moved during a shutdown. A deck that satisfies a distributed crowd load can still be inadequate under a wheel load in the middle of a panel. The specification should state the point load, the contact area and the position, alongside any distributed figure.
Two further cases belong in the same paragraph of the specification. Handrail loading matters where operatives in bulky PPE work at height and lean on parapets as a matter of routine. And where the walkway crosses process equipment, the load case may include something falling onto it from above rather than travelling along it.
Drainage, hygiene and the details that decide maintenance cost
An open deck that drains freely is the default answer in wet environments, because standing water on a walkway is both a slip risk and a place for contaminants to concentrate. Open grating also lets light through to the level below, which matters more than it sounds when the walkway runs above a working area.
In food processing the calculation changes. Hygiene requirements push towards surfaces that can be cleaned rather than surfaces that drain through, and towards details with no traps. That means closed sections rather than open channels, no upward-facing ledges collecting residue, and fixings that can be wiped rather than unpicked. A structure designed for a fish farm walkway and one designed for a processing hall differ mainly in these details, and they are the details most often left to the fabricator’s discretion.
Lighting integration is worth naming in the same section. Where the walkway carries its own lighting, an IP65 rating is the appropriate baseline for wash-down and outdoor exposure, and we supply to that as standard. Specifying it explicitly avoids a later conversation about whether fittings suitable for an indoor corridor are acceptable over a quayside.
Certification for industrial clients
Industrial buyers sometimes assume that EN 1090 is a public-sector formality. It is not: the standard governs structural components placed on the European market, and an access bridge carrying people over a working plant is a structural component regardless of who owns the site.
The part number matters, since EN 1090-3 covers aluminium execution while EN 1090-2 covers steel. So does the execution class, because an elevated structure over an occupied working area normally justifies EXC3 rather than EXC2. Insurers and internal safety functions increasingly ask for the documentation even where no public tender is involved, and it is considerably easier to obtain at order stage than three years later.
| Environment | Slip rating | Key detail |
| Dry plant, indoor | R11 to R12 | Standard fixings |
| Port, quayside | R12 | Galvanic isolation |
| Fish farm, over water | R12 | Galvanic isolation |
| Oil or grease exposure | R13 | Displacement space |
| Food processing | R12 to R13 | Cleanable, no traps |
Common questions
Can an aluminium walkway be installed without shutting the facility down?
Usually, and this is the main operational argument for aluminium in live plants. Structures arrive prefabricated in modular sections that a standard vehicle can deliver and a small crew can assemble without heavy lifting equipment. The constraint is normally crane access and the permit regime rather than the structure itself.
Does an aluminium walkway need repainting?
No. There is no protective coating to maintain, no repainting programme and no shutdown for corrosion treatment, which is where most of the lifecycle saving against painted steel comes from. Inspection is still required, but inspection and recoating are different budget lines.
How is the walkway fixed to existing steelwork without causing corrosion?
Through isolation at the interface: non-conductive washers and bushes, fastener materials chosen for the couple, and bearing details that keep the two metals apart. Tell us what the structure is being fixed to and what the atmosphere is, and the detail gets designed rather than assumed.
What load figure should go into the enquiry if we have not calculated one?
Describe the use instead of guessing a number. What crosses the walkway, how heavy is the heaviest single item, is it wheeled, and how many people are on it at once during a shift change. Those four answers let our engineers derive the load case, and they are more reliable than a figure copied from another project.
Working with DR VERSLAS
We supply certified aluminium access bridges, catwalks and inspection walkways for industrial plants, ports, fish farms, water treatment sites and food processing facilities. Decks are R12 anti-slip rated as standard, integrated lighting is IP65, and load specifications are calculated to the operational requirements of the facility rather than to a generic pedestrian class. Everything is certified to EN 1090-3 execution class EXC3 with full documentation. Send us the span, the environment and what will cross the structure, and our engineering team comes back with feedback, an estimated timeline and a price band before formal quotation. See our industrial bridges and access walkways, floating structures and pontoons and outdoor staircases, browse delivered projects, or read our public procurement checklist