Erecting a mobile scaffold / mobile access tower

Mobile access towers are regulated by DS/EN 1004-1:2020, which replaced EN 1004:2004. Maximum platform height, permitted load and stability conditions are manufacturer-specific and are stated in the assembly instructions and the CE/type-test documentation — use those, not a general estimate.

The ground must be level, firm and load-bearing, and the castors or base plates must have full contact. A mobile tower is tall and narrow — even a slight slope or a soft spot noticeably affects stability.

Build the tower from the bottom according to the prescribed assembly method — usually 'through the trap' (access through a hatch) or 'advance guard rail', where the guardrail is fitted before you step onto the next platform. That way you are protected throughout the build.

Fit the guardrail BEFORE you climb up to the next level — not afterwards.

As a guideline rule of thumb, the platform height H must not exceed 3 × the smallest base dimension b (H ≤ 3·b). The exact ratio at which outriggers/ballast become necessary is given in the manufacturer's height table — the rule here is only an estimate to catch a tower that is far too tall and narrow.

Max. platform height according to DS/EN 1004-1:2020 is 12 m indoors and 8 m outdoors. The limit is lower outside because the wind acts on the free-standing tower. If you need to go higher, a mobile scaffold tower is not the right choice.

Above approx. 3 m platform height, outriggers (outriggers/stabilisers) are mandatory (BFA). They increase the tower's base width and thus its stability. Fit them according to the manufacturer's instructions, and check that they have full footing.

Before anyone goes up to work, lock ALL wheels — no exceptions. Also check that the internal stairs/ladder rungs are fitted, so that no one ever climbs up the outside of the tower.

All wheels locked, every time — a single unlocked wheel can set the tower in motion.

Clear the platform completely of people, materials and tools before moving — nobody rides on it. Only move it on level, firm ground without thresholds, joints or holes, and push/pull at the base frame, never at the top of the tower.

No people or loose parts on the tower while moving it — always push at the bottom.

Free-standing outdoor use in strong wind requires anchorage or the tower to be taken down (BFA). Never exceed the permitted load/load class (typically class 3, 2.0 kN/m² — verify against the manufacturer's CE documentation).

Dismantle the tower in the reverse order of erection, following the manufacturer's instructions. Assess and discard damaged components, record it in the QA log, and store the components sorted and dry so they do not rust or deform.