Cranes in Arboriculture - Towards an Industry Standard
This article by David Robinson Tech Cert (Arbor.A), Anderson Tree Care Ltd was originally published in the Arboricultural Association Newsletter issue 145. The author is inviting feedback from members of the industry, who use mobile cranes for tree work. The intention is to encourage people to think about the issues associated with this type of work and to collate information that will be valuable drafting industry guidance on this topic. Comments could be submitted via 'http://www.andersontreecare.co.uk/cranes.php'
AFAG has recently introduced a new project into its workplan for 2010/11 which will be reviewing the use of cranes in arboriculture in the UK and will be looking in particular at what training and guidance is needed.
David Robinson Tech Cert (Arbor.A)
Anderson Tree Care Ltd.
It may be difficult to establish exactly when a mobile crane was first used during an arboricultural operation in the United Kingdom, but it is very apparent that since that time, their use has become increasingly popular. A quick internet search will reveal a large number of arboricultural contracting companies proudly asserting their expertise in the use of mobile cranes for the controlled dismantling of trees. It is not unreasonable therefore to assume that many of these companies utilise cranes on a regular basis.
Cranes are undoubtedly well integrated into arboricultural practice in the UK, however the lack of available information and advice pertaining to their use in the industry would suggest otherwise. The current draft version of BS 3998 Recommendations for tree work (2008) is one of only a few formal publications to acknowledge the use of cranes in the industry. In the section entitled tree felling, it states that 'cranes should be used when appropriate'. The Arboriculture and Forestry Advisory Group (AFAG) leaflet 402 (2003) mentions cranes briefly in respect of their potential use in aerial rescue. The new rigging research report RR668 (2008) promotes the use of cranes over standard rigging techniques when dismantling trees that are not sufficiently strong and includes the use of cranes when choosing a suitable safe rigging strategy appropriate to the situation being considered.
Many arborists have come to recognise the benefits that cranes bring to certain arboricultural operations in terms of safe and efficient working practice. In actual fact, these benefits extend well beyond the individual company and in to the wider industry. They include:
- Less time spent engaged in climbing the tree
- Reduced use of the chainsaw in the tree as larger pieces can be removed
- Reduced use of the chainsaw on the ground
- Reduced fatigue (The Health and Safety Executive (HSE) recognise fatigue as a contributing factor in the causes of some accidents in tree work)
- Creates a safer environment for ground staff as each piece of timber removed is under close control
- Less reliance on the unknown strength of anchor points in the tree when using conventional climbing and rigging techniques (cranes are a known strength and the subject of frequent testing)
- Reduces manual handling and strain injuries benefiting both employee and employer (reduced risk of injury and less time off work)
- Faster than conventional techniques thus providing a commercial advantage
The lack of published accident statistics relating to the use of cranes in tree work in the UK might be considered as clear evidence of the safety of this type of operation. It also lends weight to the argument that the use of cranes raises standards of safety in the industry and that they are therefore a valuable inclusion in the list of equipment available to the modern arborist.
The use of mobile cranes in tree work in the UK is governed by four pieces of health and safety legislation. In summary, the Management of Health and Safety at Work Regulations (1999) requires risk assessments to be carried out to identify all risks associated with a lifting operation and the type of lifting equipment being used. The Provision and Use of Work Equipment Regulations (1998) requires the selection of suitable work equipment in terms of its design, where it is to be used and the purpose of its use. The Work at Height Regulations (2005) requires that, work at height is properly planned, workers are competent, risks are assessed and appropriate work equipment is selected and properly inspected. The Lifting Operations and Lifting Equipment Regulations (1998) impose requirements in respect of the planning and organisation of lifting operations, the strength and stability of lifting equipment and the marking and thorough examination of such equipment.
Those contractors who are familiar with the use of mobile cranes will also be familiar with the anomaly that exists at present. Arboriculture is a highly regulated industry in terms of health and safety. Professional tree work is governed by a raft of legislation. Regular training and certification is a requirement for those employed in tree work. Large volumes of health and safety documents pack the filing cabinets and hard drives of the arboricultural managers office and guidelines produced by various industry bodies and working groups form the backbone of best practice for those engaged in arboricultural operations. Surprisingly and despite all of this, the use of mobile cranes in tree work is not currently supported by an industry guide or training qualification.
This decidedly grey area raises a number of potential issues for arboricultural companies engaged in tree work using cranes.
- What work practices currently constitute acceptable, safe practice?
- Does the lack of specific training for operatives in the use of cranes in tree work breach existing health and safety legislation?
- In the event of an accident, what guidance is available for all parties to refer to in order to establish whether or not best practice was being followed?
- What practices would insurance companies currently expect to see in order to provide adequate and effective cover?
Published advice and guidance on the use of cranes in arboriculture at present is limited. The general use of mobile cranes is covered by British Standard 7121-3. (2000). This code of practice provides specific guidance on safety when dealing with mobile cranes such as crane selection, production of method statements and selection of an appointed person, but it does not relate directly to the use of cranes in arboricultural operations. The very recent research by Detter, et al (2008) into rigging and dismantling practices used in arboriculture provides information that is of use to those engaged in crane operations. In particular, the sections relating to managing a rigging operation, establishing a safe strategy and estimating the weight of green wood, but again this document is not specific to mobile crane use.
Advice can be sought from sources further afield in the United States of America (USA). A recent revision of the American National Standards Institute (ANSI) Z-133.1 (2006) includes a new section specifically on guidance for the use of cranes. Although legislation and guidance is different in the UK and USA, this document does contain information that can be of use to the UK arborist. Other guidance produced by individuals within the American arboricultural industry is also available for download from the internet. In his article, Adams (2007) comments on the ANSI Z-133.1 document and looks specifically at the use of cranes to access and /or work in a tree that is being dismantled. In an article by Chisholm (2005) advice on best practice for tree removals by crane is offered, based on the working experience of the author.
In 2002, Mr Paul Elcoat formerly of Salcey Arborcare was instrumental in the formation of a working group set up with the intention of producing an industry guide and associated training qualification. The group included representatives from the UK and USA arboriculture industries and safety and training organisations. Unfortunately, despite making substantial progress, the group did not complete their objective and the issue has since fallen off the radar once again. In an article that originally appeared in Tree Care Industry magazine (2003), Paul Elcoat provides a brief history of the progress made by the working group and offers advice on correct procedures to be observed when using cranes. He has also produced and published to the internet a risk assessment template for the use of mobile cranes in tree work.
It could of course be argued that the current status quo should be maintained, as a lack of best practice guidance and training means that a prosecution by the Health and Safety Executive in the event of an accident is unlikely as long as all reasonable steps have been taken to minimise and manage potential risks. The production of a guidance document and training course at some time in the future, however, is inevitable regardless of the tub thumping of this author or anyone else. History shows that, for the benefit of the industry, the production of formal guidance affecting arboricultural practice is better led by those knowledgeable and experienced in arboricultural practice and not dictated to by the agendas of other stakeholders. Better then, in the author's opinion, that the industry acts now and strongly influences the production of a document that maintains all of the many benefits of mobile crane use in arboriculture, than to have a knee jerk response off the back of a serious accident. The worst case scenario in every respect would be a fatality followed by a complete ban.
The author has been in discussions with AFAG and the Arboricultural Association with the intention of once again raising the profile of this issue. A formal request was made to AFAG to include this topic on the agenda of their scheduled meeting in May and Simon Richmond has offered the Arboricultural Associations full support to this initiative. The ultimate objective is the production of an industry led, workable guide and effective training course for the use of mobile cranes in arboriculture.
The author is inviting feedback from those members of the industry who use mobile cranes for tree work. The intention of this is to encourage those people to think about the issues associated with this type of work and to collate information that will be valuable in both persuading the relevant bodies of the need for effective guidance and the subsequent production of a document.
Please visit http://www.andersontreecare.co.uk/cranes.php and complete and submit the form. I welcome your comments.
My thanks are extended to Paul Elcoat of P.W Elcoat & Associates Ltd. for his assistance in preparing this article.
- Adams, M. (2007) 'Crane Best Practices in Tree Removal: Hoisting a Qualified Arborist'. Tree Care Industry.
- American National Standards Institute. (2006) ANSI Z133.1 American National Standard for Arboricultural Operations - Safety Requirements. International Society of Arboriculture
- British Standards Institution. (2000) BS 7121-3: Code of Practice for safe use of cranes – Part 3 Mobile cranes. Milton Keynes. BSI
- Chisholm, S. (2004) Industry Best Practices for Crane Safety. Excerpted from a panel presentation atTCI EXPO Spring 2004 in Sacramento, Calif.
- Detter, A., Cowell, C., McKeown, L., Howard, P. (2008) Evaluation of current rigging and dismantling practices used in arboriculture. RR668 Research Report. HSE
- LOLER: How the regulations apply to arboriculture. (2006)AIS30 (REV1) HSE Books
- Elcoat, P.W. (2003) Standards of Best Practice for Arboricultural Crane Operations. Originally published in Tree Care Industry Magazine 2003.