CPA Bulletin

This new good practice document devised by the Construction Hoist Interest Group (CHIG) and launched in November 2019 provides guidance in an easily digestible form on the design and installation of construction hoist bases and supporting ties. All construction hoists and mast climbing work platforms (MCWPs) rely on their bases and ties for stability and applies equally to all types and sizes of machine - passenger/goods, goods only, transport platforms and MCWPs - from the smallest to the largest. Recent changes to standards for both hoists and the construction fixings used to attach ties to supporting structures have resulted in confusion in the calculation of tie loads, the design of ties and the selection of fixings to attach those ties to structures. The increasing emphasis on the management of temporary works on construction projects requires that the design of hoist bases, ties and their fixings are recorded and subjected to checking. A lack of understanding of the calculation of tie forces frequently results in excessive safety factors being applied, resulting in uneconomic tie designs requiring many fixings to attach them to the supporting structure. This has the effect of increasing costs and the difficulty of installing many fixings in one location, with the associated work at height issues. Unfamiliarity with hoist tie and base design can provide difficulties for those carrying out temporary works checks, leading to misunderstandings and delays to programme. Hoist tie and base design should always be carried out by those with the necessary skills, knowledge, training and experience to undertake this work competently. The aim of this document is to provide clear guidance on tie and base design, the selection and installation of fixings, and the presentation of temporary works information in a standard format. This new guidance can be downloaded from https://www.cpa.uk.net/construction-hoist-interest-group/ GUIDANCE ON TYING CONSTRUCTION HOISTS AND MAST CLIMBING WORK PLATFORMS TO SUPPORTING STRUCTURES (CHIG 1901) HEALTH AND SAFETY EXECUTIVE (HSE) GUIDANCE ON THE DANGERS OF WELDING FUMES Following a recent Safety Alert by the Health and Safety Executive (HSE) relating to the fumes produced by welding and burning activities, specific web-based guidance is now available for open viewing. The guidance states that although the risks to health is generally understood when dealing with certain metal types or coatings, there is new scientific evidence that exposure to all welding fumes, including mild steel welding fume, can cause lung cancer. There is also limited evidence linked to kidney cancer. Cutting fume, even where clean mild steel is involved, is equally implicated and a high standard of control should be enabled. For flame cutting work, this is likely to rely more heavily on Respiratory Protective Equipment (RPE) as engineering controls can be difficult to design, use and maintain given the aggressive production of hot fume. Nevertheless, in order to provide a clean breathing zone, engineering options that should be considered include use of portable fans to provide a directed clean air flow to displace any drifting fume from the burner’s vicinity in order to prolong RPE filter life and effectiveness. This should apply to all work activities where flame cutting is used. Engineering controls of cutting fumes in the breathing zone must be considered for all flame cutting work in a confined area, for example an enclosed space such as a workshop. It must also be considered not to rely on natural air currents to disperse fume away from the burner, such as unable to upwind of the fume when repairing plant on site. As a result of this change in categorisation, the exclusion zone around burning work and downwind of it will need to be reviewed by duty holders on a site-by-site basis. No other persons should be at work or present within the plume of fume dispersing from the area where burning work is underway unless they are using the correct level of RPE. The HSE’s web-based guidance can be viewed at http://www.hse.gov.uk/welding/index.htm TECHNICAL: 3 www.cpa.uk.net CPA Bulletin > February 2020 39