Scaffolding in lift building

Accidents repeatedly occur while working on scaffolds in lift building. Falls or collapses of the scaffolding are usually the cause for fatal accidents or severe injuries.

By Udo Niggemeier

Irrespective of whether a new lift or modernisation (replacement lifts) are involved: lift shafts are fitted with scaffolding from which work like rail placement, drive assembly or disassembly is carried out. Installing a scaffold in the shaft can also be necessary in the case of repairs. For example, this is the case if the car if the ropes are being replaced or if work on safety gear lower down is necessary.

Scaffolding is subject to the "Requirements for scaffolding" (TRBS 2121 Teil 1, DGUV-I 201-011, DGUV-I 209-053). In general, a distinction must be drawn between whether a scaffold is erected, i.e. installed, or an existing scaffold is used.

Installation of scaffolding

Photo: © Hilti Deutschland AG

When planning, consideration must already be given to the location of scaffold levels to ensure they are not in the way during later installation work (rail brackets, rail joints, landing doors with attachment, etc.) and that work can be carried out safely from the scaffold levels.

To anchor the scaffolding in the shaft, scaffolding saddles are normally used.

These are 
• inserted in scaffold bushings, which are installed in the shaft walls
• bolted to the anchor rails or cross rails of shaft scaffolding and
• anchored with dowels in the shaft walls.

Observing the information of the scaffolding saddle manufacturer is mandatory here.

If dowels are used, the stability of the shaft walls must be considered. This is normally unproblematic in the case of concrete but in the case of brickwork pull-out tests are necessary to check the stability.

Beams (rails) and planks (surfacing) are placed on the scaffold saddle. The corresponding dimensions can be found for standard shafts (up to 2.60 m x 1.80 m) in Annex 1 of the DGUV Information 209-053 (see graphic). A static calculation is required for larger shafts.

Requirements for the scaffold timber

The dimensions for standard shafts (up to 2.60 m x 1.80 m) can be found in Annex 1 of the DGUV Information 209-053. Photo: © DGUV Information 201-011

The timber used must correspond to the sorting class S10 according to DIN 4074-1 and the strength class C24 according to DIN EN 338. Attention must in particular be paid to crack formation, knottiness, rot and insect damage. The scaffold timber is often stored and later reused after completion of the lift. However, cracks and rot often arise in the timber as a result of incorrect storage, meaning S10 classification can no longer guaranteed here.

The cross and longitudinal rails must be secured against displacement, tilting and lifting. For example, this is possible by nailing to the scaffold saddle or the use of a clamp fitting. Moreover, the rails must rest full surface with a minimum overlay of 80 mm in the scaffold saddle. Tapering is not permissible.

A surfacing is placed on the rail, which usually has to consist of wooden planks which are at least 30 mm thick. These also have to be secured against displacement, tilting and lifting. This can for example be achieved by using nails or screws. The maximum distance of the planks may not be more than 2.5 cm and the horizontal distance between surfacing and shaft wall not exceed 30 cm. If the distance is greater, further measures against falling must be taken.

After completion, the installation company must have the scaffold approved by an authorised inspector and attach a release certificate.

Use of scaffolding

A scaffold may only be used if the approval certificate has been attached by the installing company and a qualified person of the client company has inspected the scaffold. The suitability of the scaffold and effectiveness of the protective and safety installations must be checked. Written proof is advisable.

The maximum distributed load can be found in the approval certificate. It may not be exceeded. Concentrated loads, like those produced by ladders, should be avoided. The user of the scaffold (fitter/technician) may not change this either. This does not include uncovering individual planks of the surfacing, e.g. for transport purposes. It must be borne in mind that further protective measures against falling are essential in the case of gaps larger than 30 x 30 cm.

These can be, for example:
• guard rails
• safety nets
• PPE against falling.

The TOP principle (technical, organisational, personal) must be observed in this regard. After the work has been completed, the planks must be returned and attached.

All users of scaffolding must be instructed by their employer on how to use it safely at least once a year.

The author is the managing director of ASIB-Niggemeier and first chairman of the Board of Management of the Association of SME Lift Companies (VmA).

More informations: https://asib-niggemeier.de/