Safe use of mobile access towers conforming to SANS 51004:2009

Discussion in 'Scaffolding, Formwork & Support Work' started by Neil Enslin, Jun 4, 2019.

  1. Neil Enslin

    Neil Enslin Moderator

    Safe use of mobile access towers conforming to SANS 51004:2009

    SANS 51004:2009 restricts the height of free-standing mobile access towers to 12,0m, where not exposed to wind and to 8,0m where exposure to wind is possible. The standard does not cover towers that are tied back to structures for added stability.


    Semi- exploded view of a typical Mobile Access and Working Tower – this model fitted with stairs

    In South Africa, safety training is mandatory for all persons working with dangerous equipment or working in hazardous environments. It is the responsibility of the employer, in terms of sections 8 and 9 of the Occupational Health and Safety Act.

    Several of the Regulations made under section 43 of the Act calls for persons to be properly trained to ensure their health and safety in connection with their work activities and environments. In the more recent regulation such as the Construction Regulations 2014 and Driven Machinery Regulations 2015 the emphasis is placed on competence and “competence” is defined to require inter alia that training be done against NQF registered qualifications where these exist.

    This is the current dilemma facing the work at height industry. There are no applicable QCTO / SAQA registered Occupational Qualifications for this industry. The legacy of poorly written, and in many cases, inappropriate Unit Standards dominate the skills development activities.

    To make matters worse, the current, as well as the newly proposed amended, NQF Act does not address skills programmes and only deals with Qualifications and Part-Qualifications whereas the vast majority of training that is required to meet the provisions of the Regulations, are in fact skills programmes.

    Mobile access tower training.

    The only SAQA registered Unit Standard on the NQF for mobile access tower assembly training is # 243275 with 4 credits at level 01 entitled “Erect and dismantle prefabricated aluminium alloy scaffolding”.

    This Unit Standard was created some twelve years ago and does not distinguish between the two accepted assembly methods viz: - “Through-the-trap door” (3T) or “Advanced Guard Rail” (AGR). This Unit Standard, along with many others are being phased out, to be replaced with modules which will form part of occupational qualifications. When skills programmes are formally recognised on the NQF then these modules could be made available as stand-alone Skills Programmes.

    The Institute for Work at Height has been appointed as Qualification Development Partner of the Quality Council for Trades and Occupations (QCTO) responsible for developing a new series of occupational qualifications for the Work at Height industry. Mobile access tower training is included.

    The Two different assembly methods

    • Through-the-trap door - 3T
    3T stands for ‘Through The Trap Door’ and is an approved method of assembly by Britain’s national regulator for workplace health and safety (HSE) that reduces the risk of the assembler falling. Using this method, the assembler sits on the platform with a trap-door to add or remove any guard rails above. This system protects the assembler from standing on an unprotected platform. Once guard-rails are secured in position, the assembler can stand upright on the platform and continue constructing the next level.

    • · Advanced Guard Rail - AGR
    AGR stands for ‘Advanced Guard Rail’ which are rails that can be assembled on the next level above the one on which the assembler is standing. There are two types of system available known as ‘additional’ or ‘integral’. The ‘additional’ system means that as each level is assembled, a permanent guard rail is added in place of the AGR, which is moved up to the level above. The ‘integral’ system forms the advanced guard-rail as part of the tower structure, so it remains in the same position until the tower is dismantled.

    In either case, the towers should comply with the requirements of the South African National Standard- SANS 51004:2009 “Mobile access towers made from prefabricated elements- Materials, dimensions, design loads, safety and performance requirements”.

    Which is the safer system?

    This is a subjective question but if you are using the AGR system correctly, means you are never exposed to the danger of falling by standing on an unguarded platform. However, whilst the 3T system is more cost effective, if used according to the instructions it is also a method approved by the HSE for assembly of tower scaffolds. AGR systems are generally more expensive because there is more material used, more welding and cast components in each level. The positive part is there are fewer overall components and it is harder to build incorrectly.

    Training and Licencing

    Building owners and other clients should ensure that when their contractors intend using mobile towers on their premises, that the person in charge (the assembler) is certified and holds a licence issued by a SAQA recognised Professional Body.

    The skills development provider offering the training on this Unit Standards must be registered with Department of Higher Education and Training and accredited with the relevant SETA. Under the current training dispensation, the provider must make use of SETA registered Assessors and Moderators –

    When the new National Qualifications Framework Act is promulgated, accreditation of the Training Providers will fall under the QCTO. Note that under the new act, only registered and accredited providers can offer the training. The revisions to the National Qualifications Framework Act specifically address issues of fraud and misrepresented qualifications.

    source: saiosh news letter