Construction Consultation

TECHNICAL COMMITTEE UPDATE

The Technical Committee has been hard at work on TG20:21 since the software was released in April. (See page 10 for more).

The Guides have been issued as well as a short PowerPoint training presentation (downloadable from the NASC website), which provides information for scaffolders regarding the principal changes from TG20:13.

The TG20:21 Working Group has also been working through comments and suggestions made by users. Many amendments and improvements have been made to the Operational and Design Guides as a result of this feedback.

The Working Group will now turn its attention to liaising with CADS to prioritise improvements and expansions of the TG20:21 software.

Other guidance notes, which will soon be available, include the folllowing:

TG8:21 FIRE DAMAGE

The NASC is often asked if scaffolding equipment that has been exposed to excessive heat, such as during a building fire, can be safely re-used. Unfortunately, there is no simple answer to this question as a great deal depends upon the temperature generated by the fire, the time the equipment was exposed to that temperature and the type and grades of materials that were used to manufacture the equipment.

Some components, such as those manufactured from timber, plastic or GRP will display significant damage at relatively low temperatures and should be immediately discarded. At higher temperatures, the strength of most metals decreases and this can often have a permanent effect on their strength when they return to normal temperatures.

Another critical factor is how rapidly the material is cooled from the high temperature. Cold water used to extinguish the fire could result in rapid cooling, leading to the material becoming brittle.

TG8:21 was therefore produced to explain the potential issues and the action to be taken if such equipment has been subjected to a fire or conditions of extreme heat Scaffold tube storage racks are a common feature of every scaffolding contractor’s yard and many long-term live sites. Whilst tube racks are usually constructed as basic birdcage-like structures, they generally support many tonnes of equipment, so their design needs special consideration.

This guidance note therefore considers the design, use and maintenance of scaffold tube storage racks.

A ‘typical’ generic design for an unclad scaffold tube rack is included within this guidance, which can be used in place of a bespoke design in all but the most exposed areas of the UK.

The Technical Committee continues to produce industry-leading guidance. Topics for the review and development of future guidance notes include:

• Guide to the Design and Construction of Temporary Roofs and Buildings

• Fire Retardant Treatments for Timber Scaffold Boards and Battens

• The Management of Temporary Works to BS 5975

• Identification of EN74-1 Couplers

• The Lacing and Bracing of Beams

• Non standard Boarded Platforms

• Scaffold Board Nailplates

• Anchoring to the Ground

• Edge Protection

TG16:21 ANCHORING TO THE GROUND

Many free-standing scaffolding structures, such as access towers, lighting towers, major signboards, power line crossings, fences and enclosures, need to be anchored to the ground, primarily to resist wind forces. This can provide substantial cost savings over other methods of restraint, such as fitting large buttresses and the use of ballast.

TG16 provides guidance on the requirements of ground anchorage and factors of safety which should be adopted.

This document has been reviewed and updated to include additional information regarding hazards due to underground services, installation information, connections, and anchors in concrete. It also includes information regarding additional types of ground anchors which are now available.

BRITISH AND EUROPEAN STANDARDS

The NASC continues to serve as the UK scaffolding industry representative on a number of international scaffolding bodies.

The European Committee for Standardisation (CEN) have created a working group to produce a ‘core standard’ for scaffolding and access. This will combine current temporary works related codes such as EN 12810, 12811, 12812 and 13374, to form an over-arching standard which would remove any currently existing anomalies.

Whilst this is a huge undertaking which could take a number of years to complete, work is now underway and the first meeting of the working group has taken place to agree the scope.

The periodical review of EN74 parts 1 and 2 (Scaffold Couplers) has now been completed and revised documents are expected to be published later this year.

Work currently being undertaken by the British Standards Institution (BSI) includes the review of BS 1139-2.2 - Metal scaffolding. Couplers and fittings. Couplers and fittings outside the scope of BS

EN 74, BS EN 13374 - Temporary Edge Protection Systems and BS 13700 - Permanent Counterweighted Guardrail Systems.