Use of concrete vats with a work platform

A vat fitted with a platform is often used when pouring concrete to build high columns and walls. A worker can stand on the platform and his job involves opening the valve of the vat of concrete when it has been placed in the correct position. The whole system is suspended from a crane.

The following questions have been asked about the use of concrete vats with an integrated platform on which the worker stands and is raised with the vat.

• Is this technique authorised?
• Which regulatory requirements must be met?
• Are there any additional safety conditions to be met to guarantee maximum safety?

In terms of whether this technique is authorised, we can state that nowhere in the General Labour Protection Rules or the Code on Well-being at Work this method is explicitly prohibited.

In terms of the application of the regulatory requirements, we can find the basic legislation in the Code, more specifically in section 4 on work equipment for lifting and hoisting loads in book IV of the Code. Articles IV.4-7 and IV.4-18 to IV.4-21 of the Code apply here, with the principle that the lifting of persons is only authorised in exceptional cases.

As a result of this provision, we can therefore state that the permanent use of this type of concrete vat is not authorised, as its exceptional nature cannot be demonstrated.

In application of Article IV.4-19 of the Code, the entire equipment (crane + concrete vat with platform) must be inspected by an external service for technical inspections in the workplace when it is commissioned and then periodically afterwards.

Under no circumstances is there a derogation from the requirements of section 4 of book IV of the Code.

The provisions of the General Labour Protection Rules, namely Article 453 , available in French (l’article 453 (PDF, 28.66 KB)) and Dutch (artikel 453 (PDF, 25.72 KB)), do not in themselves constitute basic legislation for this application. The sole purpose of referring to Article 453 of the General Labour Protection Rules in Article IV.4-21 of the Code mentioned above is to maintain a number of characteristics and criteria for use in the new legislation.

Compliance with a number of these criteria is not self-evident, for example:

• lifting speed: this cannot exceed 20 m/min;
• lifting capacity: the reduction of the authorised load by half applies to ALL positions and therefore not just the maximum lifting capacity;
• in terms of Article 453.12, it is certainly advisable to recommend that the number of persons be limited to one.

Furthermore, it is important to ensure that the lifting mechanisms are used by competent persons (Cf. Article 453bis of the General Labour Protection Rules, available in French (l'article 453bis du RGPT (PDF, 12.07 KB)) and Dutch (artikel 453bis van het ARAB (PDF, 8.96 KB))).

The Well-being at Work legislation, in particularly the use of work equipment, also provides for an assessment of all work-related risks. All the risks involved in the concept of lifting or hoisting persons are therefore subject to assessment and analysis as part of the prevention policy.

Additional requirements to guarantee maximum safety:

• Have written instructions on site for personnel and inform the line management of the construction site.
• Ensure that there is no interference with other lifting equipment. If there is, ensure that the equipment operators in charge of the lifting equipment sign clear, unequivocal instructions and agreements (a kind of protocol between the crane operators). When interference is possible, it is advisable to stop the mechanism for the entire period that the worker is present on the concrete vat.
• Carry out activities under the permanent and adequate supervision of a person who is in direct contact with the crane operator and with the worker on the concrete vat. This must be correctly supervised.
• The contents of the concrete vat cannot exceed half the admissible load of the lifting equipment; this applies to any possible position of the concrete vat.
  The crane must be fitted with a load limiter that takes account of the reduction by half of the authorised load.
• Pay attention to protecting the worker on the platform against the consequences of a collision with a fixed obstacle. It is absolutely vital for the platform protection to be strong enough to withstand crushing.