What do the class ratings and markings on a ladder mean?

The label on the side of a ladder is not marketing. It states what standard the ladder was tested to, what duty it is rated for, and how much total load it may carry, and the difference between grades is real — stile thickness, rung fixing method and the number of test cycles it survived.

Safety

Step by step

1. Find the label.Usually a sticker on the inside of a stile near the bottom. It gives the standard, the classification, the maximum load, the maximum working height and often a manufacture date and a serial number. If a ladder has no legible label, you do not know what it is rated for.
2. Understand the current EN 131 split.Ladders to EN 131 are marked as either non-professional or professional. Non-professional is for domestic use; professional is built for daily trade use and tested to a much harder duty cycle. Both carry a stated maximum load, which is commonly 150kg for a modern ladder.
3. Recognise the older British class system.Ladders predating the harmonised standard are marked Class 1 (industrial, heaviest duty), Class 2 or EN 131 (trade), and Class 3 (domestic, lightest). Class 3 is the one to be wary of for anything demanding — it was built to a price for occasional light household use.
4. Read the load rating properly.The figure is total load: your body weight, boots, clothing, a tool belt, a bucket of anything, and the tool in your hand. A 95kg person with a full belt and a bucket of tiles is close to a 150kg limit, and that is before any dynamic loading from moving about.
5. Note the working height, which is not the ladder length.Manufacturers state a maximum working height that assumes you stand a safe distance below the top and reach a normal amount. For a leaning ladder you must also allow that it will be at a slope and must project about a metre past the point you step off.
6. Check for the EN 131 stability requirements on modern ladders.Ladders sold since the standard was updated must have a stabiliser bar or a widened base above a certain length. A wide-base ladder is meaningfully more stable sideways, which is the direction most leaning ladders fail in.
7. Match the ladder to the environment.Aluminium is light and stiff and conducts electricity. Fibreglass stiles are non-conductive and are what you want anywhere near overhead lines or electrical work, at the cost of weight and price. Timber ladders are heavy and must never be painted, because paint hides splits.
8. Keep the label legible.It carries the inspection information as well as the rating. Do not paint over it, and if it is peeling, photograph it so the information survives.

Tips

• The price gap between a domestic-rated and a professional-rated ladder of the same length is usually smaller than people expect, and the professional one is stiffer, heavier and lasts far longer.
• A stepladder's rating is quoted the same way, and the top platform on a domestic stepladder is often not rated as a standing surface at all — the label says which step is the highest you may stand on.
• Second-hand ladders are a poor bargain. You cannot see fatigue, and a ladder that has been overloaded or dropped may look perfect.
• If you are heavier than average, or you work with a loaded tool belt, check the rating specifically rather than assuming 150kg covers everyone.

Questions people ask