Lifts in wind turbines
To fulfill sustainability objectives, wind turbines are being installed across the whole of Europe. They are often equipped with a lift as standard. These days, wind turbines of a height exceeding 60 meters are often provided with a lift as standard, though this is combined with a ladder in case the lift is out of service and for emergencies. The ladder is often equipped with a climbing aid.
Area of tension
The ‘wind-turbine market’ is predominantly determined by the manufacturers of the towers in the wind turbines. These manufacturers are generally geared towards European requirements. They, together with the client for the construction of the wind turbines, determine what happens in the towers and which installations will be fitted there. So the lift manufacturers have no say in what happens in the towers. There are standards both for the construction of the towers and for the installation of the lifts, although they may be conflicting. This can therefore lead to tension, which demands a fair amount of consultation.
Machinery Directive rather than Lift Directive
Lifts in wind turbines are not covered by the Lift Directive. Excluded from the Lift Directive are lifts moving at a pace slower than 0.15m/s, as well as lifts connected to machinery and intended exclusively for access to workstations including maintenance and inspection points on the machinery. Lifts in wind turbines are part of this last category. Characteristic for these lifts is also that they are only used by instructed authorised personnel. In addition, they are used in a confined environment, so that there is no risk of children, for example, getting inside these lifts. Lifts in wind turbines still have to comply with the essential safety requirements of the machine directive instead of the lift directive. Many hazards are similar although the specifics risks can differ.
As there is a risk in lifts in wind turbines, according to Appendix IV of the European Machinery Directive, of people falling more than 3 metres, a type inspection of these lifts is mandatory. This inspection can be carried out in two ways: By the supplier themselves, providing they are ISO module H certified, or by a notified body for type inspections, such as Liftinstituut. In time, there will likely also be type inspections based on a standard harmonised worldwide, but this is not available as yet. At the close of the commercial phase, national legislation is defining.
No product standard (as yet)
For this type of lift installations there is no harmonised product standard available in Europe as yet. However, a standard for lifts in wind turbines is being worked on. This will be the standard prEN 81-44
At the moment, there are various manufacturers with EC certified wind turbine lifts providing various safety facilities. As a result, the Machinery Directive Working Group of the European Commission has drawn up a ‘Recommendation for Use’ (RFU). This is a working document for notified bodies.
Main requirements of the RFU for wind turbine lifts
The main requirements of this RFU are:
- In order to prevent impact and trap risks at the stops and if the distance from the platform to the ladder is less than 0.5 metre, both the bottom and top of the platform must be provided with a safety feature.
- The stops must be provided with doors or fencing, complemented by the above-mentioned impact and trap risk safety feature. If the distance from the platform to the stop is greater than 0.5 metre, fencing only will suffice.
- It must not be possible for the barriers to be opened at the stop before the platform has reached the required floor level.
- It must be possible to use additional facilities to open the barriers for when the ladder is used (if provided) when the platform is not there.
- It must not be possible to open the platform door between the floor levels. If this is essential for maintenance purposes, it must not be possible to lift/lower the platform any further and additional measures must be taken for the user to prevent falling from height.
- Due to a lack of space and the risk of falling objects, the platform must generally be fully closed.
- Measures must be taken to be able to evacuate the users in an emergency.
Liftinstituut has been appointed as notified body for this specific work area and is well informed. Please do not hesitate to contact us if you have any questions.