A manhole step is the only thing between a worker and a fall in a confined space, and EN 13101 exists because that is not a figure of speech. It specifies exactly what the step must survive: 2 kN vertical load with deflection ≤ 10 mm and permanent set ≤ 2 mm; 4 kN with deflection ≤ 50 mm (class I); a 5 kN minimum pull-out (unfixing) resistance so it cannot come out of the wall; and a 20 kg mass dropped from 1 m. It also sets geometry: non-slip relief ≥ 2.5 mm and a side guard ≥ 20 mm. And testing is per batch of 1,000 steps, not once forever. On a PP step, the plastic is not the structure — the steel bar inside is.
1. What is actually at stake
Most articles about manhole steps are shopping guides — sizes, colours, prices. Here is the reframe that should govern how you buy one.
A worker climbs into a dark, wet, greasy shaft, backwards, carrying something, with no room to fall safely and often no room for a rescue. The step is the entire fall-prevention system. There is no second component. There is no redundancy. If the step bends and holds, that is a bad day. If it comes out of the wall, or a boot slides off the end of it, that is the incident everybody remembers.
2. The four tests, with the numbers
These are the requirements, and the reason each one exists:
And the fifth requirement nobody asks about: torsion
Look at how a step is actually used. Nobody places a boot dead in the centre. They stand near one end, in the dark, half-turned. That loads the step in torsion, not just bending.
EN 13101 limits the twist to 5 mm across the extension of the front bar. It is the requirement that most closely models real use — a foot on one end — and it is the one that never appears in a sales conversation. Ask about it, and you will learn a lot about the supplier.
3. The geometry that stops the slip
Here is the part engineers under-rate. The realistic failure of a manhole step is not that it breaks. It is that a wet, greasy boot slides off it, sideways, in the dark.
So the standard specifies shape, not just strength:
| Requirement | Minimum | What it prevents |
|---|---|---|
| Non-slip relief | ≥ 2.5 mm, distributed over the whole tread | A boot sliding forwards or backwards off a smooth, wet tread. A relief in one patch is not compliance — it's decoration. |
| Side guard / flap | ≥ 20 mm high | A boot sliding sideways off the end of the step — the failure people don't design for and do fall from. |
4. The plastic is not the structure
"Plastic manhole step" is a misleading name, and it makes people buy on the wrong attribute.
The steel bar inside
The steel core provides the strength and stiffness that pass the 2 kN, 4 kN and torsion tests. Every deflection number in the standard is a property of that bar. Ask what grade it is.
The polypropylene encapsulation
Not structure — protection and interface: a corrosion barrier against a permanently wet, aggressive sewer atmosphere; the non-slip tread; and electrical insulation. Its job is to make the steel last and the boot stay put.
5. Testing is per batch, not per decade
This is the compliance detail that separates a real supplier from a certificate collector.
EN 13101 requires an individual test for each batch of 1,000 steps manufactured. That is ongoing verification of production — not a single type test, done once, referenced forever on a PDF with a date three years ago.
6. What to ask the supplier — the checklist
2 kN test result: deflection and permanent set.The permanent set is the number that shows whether it yielded.
4 kN test result against the class you are buying.
Pull-out (unfixing) result: ≥ 5 kN.This one is about the anchorage, and it is the one that becomes a fall.
Impact result: 20 kg from 1 m — and whether the encapsulation cracked.
Torsion: ≤ 5 mm across the front bar.Ask this one. It tells you whether they actually test.
Geometry: tread relief ≥ 2.5 mm across the whole tread; side guard ≥ 20 mm.
Batch test records — one per 1,000 steps — for your batch.
Steel core grade, and confirmation the encapsulation is complete with no exposed steel at the ends.
7. Frequently asked questions
What is EN 13101 and what does it cover?
EN 13101 is the European standard for steps used in underground man-entry chambers — manholes, inspection chambers and similar. It sets the requirements, marking, testing and conformity evaluation for the step: the loads it must carry without excessive deflection, the force needed to pull it out of the wall, the impact it must survive, and the geometry that stops a foot slipping off it. It is the document that turns "a step" into a verified fall-safety component.
What load must a manhole step withstand under EN 13101?
The step is loaded vertically and its deflection is measured. Under a 2 kN vertical load the deflection must stay within 10 mm, and the permanent (residual) deflection after the load is removed must be no more than 2 mm — the step must spring back, not stay bent. A higher load test applies 4 kN, under which deflection must stay within 50 mm for a class I step. The permanent-set limit is the important one: a step that stays deformed has yielded.
What is the pull-out (unfixing) requirement?
The step must resist being pulled out of the chamber wall with a minimum effort of 5 kN. This is a different failure from bending: it is the anchorage into the concrete or brickwork failing, not the step itself. It matters because a step that bends is frightening, while a step that comes out of the wall is a fall. The anchorage legs and the way the step is embedded or fixed are what deliver this number.
What is the impact test for a manhole step?
A 20 kg mass is dropped onto the step from a height of 1 m. This tests what happens when the step is hit — by a dropped tool, by a worker landing on it, by material falling down the shaft — and specifically whether the step, or its plastic encapsulation, cracks or shatters rather than absorbing the blow. A brittle step that survives a static load test can still fail this one, which is why it is in the standard.
On a plastic manhole step, what actually carries the load?
The steel bar inside it. A polypropylene manhole step is a steel core encapsulated in PP — the steel provides the strength and stiffness that pass the load and deflection tests, while the polypropylene provides the corrosion barrier, the non-slip grip and electrical insulation. This is why "plastic step" is a misleading name and why the encapsulation matters: if the PP is cracked or the steel is exposed, the corrosion barrier is gone and the component is on a clock.
What non-slip and side-guard geometry does the standard require?
The tread must have a non-slip relief — a pattern standing proud of the surface — of at least 2.5 mm, distributed across the whole step rather than in one patch. And the step must have a side guard or flap at least 20 mm high, whose job is to stop a boot sliding sideways off the end of the step. Both requirements exist because the realistic failure is not the step breaking; it is a foot slipping off it in the dark, on a wet, greasy tread.
How often must manhole steps be tested?
EN 13101 requires an individual test for each batch of 1,000 steps manufactured — that is, ongoing verification of production, not a single type test done once and referenced forever. When you ask a supplier for evidence, ask for the batch test records, not just a certificate with a date on it from three years ago.
Why is torsion (twisting) limited?
Because a step is normally stood on with one foot, near one end, not centrally. That loads it in torsion as well as bending. EN 13101 limits the twist across the extension of the front bar to 5 mm, which is what stops the step rolling under an off-centre boot. It is the requirement that most closely models how a step is actually used, and it is the one people never ask about.
What should I ask a manhole step supplier for?
Evidence against the standard, not a claim of it: the batch test records (one per 1,000 steps), the deflection and permanent-set results at 2 kN, the 4 kN result, the 5 kN pull-out, the 20 kg / 1 m impact result, and the tread relief and side-guard dimensions. Also the steel grade of the core and confirmation that the encapsulation is complete, with no exposed steel at the ends. A step marked to the standard but with no test data behind it is a marked step, not a compliant one.
References
- EN 13101 — Steps for underground man-entry chambers: requirements, marking, testing and evaluation of conformity. Read the standard itself before you specify against it; this guide is a summary, not a substitute.
Need manhole steps with the batch test records to back them?
20+ years of export experience. PP-encapsulated steel-core manhole steps, tested to EN 13101 with batch records available — load, permanent set, pull-out, impact and torsion. Ask us for the numbers, not just the certificate.
