In ideal conditions (load close to the body, at hip height, straight back, no twisting or bending, good grip and good environment), the INSST guide, following ISO 11228-1, gives these maximums:
| People | Aged 20 to 45 | Under 20 or over 45 |
|---|---|---|
| Men | 25 kg | 20 kg |
| Women | 20 kg | 15 kg |
The further the task is from ideal conditions, the lower the maximum weight.
Cases that need separate analysis
- Seated: you cannot use your leg strength, so arms and trunk do the work.
- In a team: two people have two thirds of the sum of their capacities; three people, half of the sum.
- People or animals: they can move suddenly (care homes, hospitals, nurseries, farms).
In practiceTwo co-workers who could each lift 25 kg do not add up to 50: together, the reference
is about 33 kg, and they must also coordinate the movement.
Source: INSST, Guía técnica de manipulación manual de cargas (technical guide, 2024 edition, in Spanish), comments on the annex, point 1, tables 1 and 2 · INSST, Guía técnica de manipulación manual de cargas (technical guide, 2024 edition, in Spanish), comments on article 3.2