EUROPEAN LAW UNI EN 13155

5.1 General requirements
The attachments shall comply with the safety requirements and/or measures of this clause. In addition, the attachment shall be designed according to the principles of EN 292 for hazards relevant but not significant which are not dealt with by this standard.

5.1.1 Mechanical load bearing parts
5.1.1.1 The mechanical load bearing parts shall have a mechanical strength to fulfil the
following requirements:
1) the attachment shall be designed to withstand a static load of three times the working load limit without releasing the load even if permanent deformation occurs;
2) the attachment shall be designed to withstand a static load of two times the working load limit without permanent deformation.

5.2.5.3
Lifting forks for loose material (e.g. bricks and tiles) to be used ina building area shall have a secondary positive holding device (e.g. net, cage).
The secondary positive holding device shall prevent the realease of the complete load or any loose parts of the load.
For handling loose materials (e.g. bricks and tiles) the secondary positive holding device (e.g. nets or cages) shall not have side and bottom openings of more than 50 mm square. Note It is recommended that the secondary positive holding device is automatically activated.

5.2.5.4
Lifting forks fitted with a secondary positive holding device required in the clause 5.2.5.3 shall be capable of holding a uniformly distributed load equal to 50% of the WLL in all four horizontal directions.

5.2.5.5
Lifting forks for unit load (e.g. plastic wrapped palletised load) to be used on building area shall have a retaining device (e.g. chain, strap or bar) to prevent the unit load sliding off the forks.

5.2.5.6
Lifting forks with a retaining device as equired inclause 5.2.5.5 shall be capable of holding a uniformly distributed load equal to 50% of the WLL.