Checks the imposed load on a scaffold bay or working platform — people, materials, and equipment — against the bay's rated capacity using the standard BS EN 12811-1 load classes.
Read before use: This checks the imposed (live) load against the scaffold's rated load class for the bay area entered — it does not check the scaffold's structural design, tie spacing, base/foundation, or board span capacity, which need their own competent-person assessment. Always confirm the actual load class marked on the scaffold's handover certificate/tag, and never assume a class if it isn't posted.
Scaffold rating
Bay dimensions
Bay = the platform area between adjacent standards/uprights being checked, not the whole scaffold. Check each bay separately — loading isn't necessarily even across the whole platform.
Imposed load on this bay
Include everything actually on the platform: workers (with tools/PPE), stacked materials, and any equipment or plant — not just the people. Don't include the scaffold's own weight; the load class already accounts for that.
BAY LOAD CHECK
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Bay area—
Allowable load—
Imposed load—
Utilization—
Quick reference
BS EN 12811-1 load classes
Class
kN/m²
Typical use
1
0.75
Inspection only — no load
2
1.50
Light duty
3
2.00
Light duty
4
3.00
General building maintenance
5
4.50
General purpose / masonry
6
6.00
Heavy duty
What this doesn't check
Board span capacity — an individual board's safe load also depends on the span between transoms/supports; check the board or staging manufacturer's own span/load table separately
Point loads — a load class is a distributed (UDL) rating; a heavy item concentrated in a small area can locally overload a board even within the class rating
Structure, ties, and base — this only checks the platform's imposed load, not the scaffold's overall structural design or foundation
Good practice
The load class must be confirmed against the scaffold's actual handover certificate or tag — never assume a class
Never exceed the lowest-rated bay, board, or component in the platform
Spread heavy materials across bays rather than concentrating them in one location
Re-check loading whenever the intended use of the platform changes
Why this matters
Overloading a working platform is one of the most common causes of scaffold collapse and falls from height
Materials and equipment are frequently underestimated compared to the people actually working on the platform
A scaffold tagged for one load class is sometimes reused for heavier work without re-assessment — always re-check when the task changes