BCD 2017

66 T H E B U I L D I N G C O N S E R VAT I O N D I R E C T O R Y 2 0 1 7 site inductions are provided, that reasonable steps are taken to prevent unauthorised access, that workers are consulted and engaged in securing their health and safety, and that welfare facilities are provided. Contractors – these are the individuals or companies who carry out the construction work. They must plan, manage and monitor construction work under their control so that it is carried out without risks to health and safety. For projects involving more than one contractor, they must co-ordinate their activities with others in the project team, and in particular, they must comply with directions given to them by the principal designer or principal contractor. For single- contractor projects, contractors must prepare a construction phase plan. Workers – these are the people who work for or under the control of contractors on a construction site. They must be consulted about matters which affect their health, safety and welfare, and their duties include: taking care of their own health and safety and that of others who may be affected by their actions; reporting anything they see which is likely to endanger either their own or others’ health and safety; and co- operating with their employer, fellow workers, contractors and other duty holders. RISK MANAGEMENT ON CONSERVATION SITES The nature of the work and the types of buildings and sites in the heritage portfolio present unique health and safety challenges. Each of the topics below could be the subject of a separate article but it is worthwhile highlighting each as being of particular relevance to heritage projects. Access for survey, investigation and preliminary works Most heritage projects will require high level access for surveys at some point, and falls from height are one of the major causes of fatalities in construction. Not all those who are killed or injured while working on roofs are roofers – many people accessing roofs are carrying out other tasks, such as maintenance and surveying, and they too need appropriate access arrangements. If scaffold access is not available then a mobile elevated working platform (MEWP) will be the next best option, but these too present significant dangers. Most professionals will rely on the expertise of the MEWP hire company, but it is important to ensure that use of the machine is properly planned and managed. A risk assessment tailored to the site and the operations involved should be carried out first. This should cover, but not be limited to, the following: • site conditions such as confined overhead working, ground conditions and the need for outriggers, falling objects and any nearby hazards • the operations involved and the need for guardrails or fall-arrest systems, and precautions for handling materials and equipment • weather conditions. PRE-EXISTING RISKS Historic buildings contain materials and conditions such as asbestos and lead paint which present latent risks. Asbestos Commercially mined from 1870, asbestos was used for a wide range of purposes in buildings. Despite awareness of its toxicity from the early 20th century, the sale of brown and blue asbestos was only banned in the UK in 1985, while white asbestos remained legal until 1999. Consequently, there are a large number of properties with a wide range of asbestos containing materials (ACMs). Asbestos is still the biggest industrial killer by far. It is estimated that even now an average of approximately 5,000 people die from asbestos-related diseases in the UK each year. It is commonly found in: • lagging around boilers or pipework • insulating boards, typically in gas meter cupboards or behind panel heaters • loose-fill insulation • as a composite in fuse boxes and switchgear • floor and roof tiles • textured coatings, such as Artex. As a minimum, owners of buildings should commission an Asbestos Management Survey, by a specialist contractor, preferably registered with the Asbestos Removal Contractors Association (see Further Information); this comprises a visual inspection combined with sampling of suspected materials for laboratory analysis. If work is to be carried out, a refurbishment survey will be necessary, and it is mandatory that all contractors carrying out work on the site (including conservators) have received formal Asbestos Awareness Training, or a refresher course, valid within the last 12 months. Removal of asbestos is likely to require listed building consent and confirmation should always be sought from the local authority beforehand. Lead paint Lead carbonates were used widely in oil-based paints until the 1960s and they are still found widely in historic buildings. It is safest to assume that any building constructed before 1970 contains some lead paint, and it is often possible to identify examples by the distinctive rectangular cracking which develops as they age. Lead paint is usually to be found in earlier layers of paint beneath later redecorations. Any disturbance of this paint needs great caution to protect the worker and occupants, and if it must be removed, strict safety controls such as wet working and respiratory equipment should be employed. However, if the paintwork is not damaged or in poor condition, attempting to remove it might result in greater exposure to lead dust than if it were left undisturbed. Advice is available from the British Coatings Federation and the Lead Paint Safety Association (see Further Information). Historic plaster Lime-based plaster was reinforced with animal hair, usually from horses, cows, goats or oxen. There is a very minor risk that animal hair incorporated into plaster mixes before about 1900 (when greater controls were introduced) could be contaminated with anthrax. This is a disease of animals that can be transmitted to humans through skin lesions, inhalation or ingestion and causes skin or pulmonary infections. Generally, it is a very rare disease in the UK and the risk is very low that anthrax will be contracted from working with historic plaster. Structural conditions Structural conditions and risks may be subject to change so they should be reviewed regularly throughout construction. Loughborough University have produced a report, ‘Avoiding Structural Collapses in Refurbishment: A Decision Support System’, which deals with this issue (see Further Information). CONSTRUCTION RISKS The methods and materials used for conservation projects can also present risks and these need to be addressed. Stone Inhalable dust can cause irritation of the eyes, nose and throat, but it is the fine respirable dust which is of prime concern as a cause of serious long-term health problems, such as pneumoconiosis and silicosis. Most serious health effects are due to regular and prolonged exposure to stone dust over past decades. It is often assumed that modern working conditions are better, but for stonemasons this may not be so. It is possible that dust exposures have gone up in the last couple of decades with the introduction of electrically powered disc cutters and polishers. It may be that silicosis and other adverse health effects among stonemasons will also rise. Proper personal protective equipment (PPE) and environmental controls need to be adopted. A craftsperson wearing safety glasses, overalls and ear protectors while preparing metalwork (Photo: iStock.com/linephoto)