Carry out aerial tree rigging

This standard covers aerial tree rigging. It includes the removal of sections from a tree crown under the control of rope rigging and lifting gear. The work will be carried out by an operator with extensive experience of arboriculture operations and chainsaw operations in a canopy.

This aerial work must be supported by ground workers with extensive experience of aerial treework and rigging techniques.

This standard covers the use of rigging for the removal of small tree sections. This is in relation to pruning operations, where targets below may pose a significant risk, and includes the removal of part/whole trees, where targets do not allow for free-fall/hand-thrown techniques.

You could be working to a given specification that defines the methods to be used but you will be expected to determine how to carry out these methods on site.

You will need to take account of any restrictions affecting the work e.g. designated sites, presence of listed structures, wildlife, non-native invasive or protected species etc.

You are required to avoid or minimise damage or disturbance to the surrounding area including trees, other vegetation, wildlife and habitats, or to any structures, fences, paths, signs, ditches/waterways or drains, and to ensure that other site users are not put at risk by your work.

When working with equipment and machinery you must be appropriately trained, competent to carry out the activity being undertaken, and hold current certification where required, in line with the relevant legislation.

Your work must conform to all relevant legislation and codes of practice, industry standards and guidance.

This standard is only suitable for those who are already competent in accessing trees by climbing.

Falls from trees or being hit by falling trees, sections of trees or branches can kill or seriously injure workers on site or those passing by.

Confirm that:
• safe practices are adopted for accessing and working in trees
• the layout and organisation of the work area protects all parties from the risk of falling objects
• risk zones are established and people are prohibited from entering the zone
• risk zones are, where reasonably practicable, clearly marked, signed and guarded
• communication methods between all workers on site are robust and effective

Additional resources may be required on site, such as banksmen, to help manage any risk associated with anyone possibly entering the work site.

1. obtain the relevant information to carry out the work activities in accordance with organisational procedures
2. check any statutory requirements that might be in place that may prohibit or place conditions on the work to be carried out, and confirm that all required permissions and licences have been obtained
3. maintain the health and safety of yourself and others at all times, in accordance with the relevant legislation and codes of practice
4. assess the risks associated with the site, the tree, working at heights and the work to be carried out, before starting work and throughout the activity, checking and confirming the findings of any existing risk assessments
5. consider the effect of disease, defects and decay on the treework operation and obtain professional advice where you are unsure
6. confirm that sufficient control measures are implemented, risk zones and drop zones have been set up and marked, and emergency planning and procedures relevant to the site have been established and recorded
7. select an appropriate access method and rescue plan for safe working at heights
8. select the safest working methods, making use of mechanical methods where this is safer, in accordance with the assessed risks and organisational procedures, and plan work accordingly
9. confirm that relevant training, experience and certification is in place to undertake the work to be carried out and recognise your own competence limitations
10. use appropriate methods to maintain effective communication with other workers and anyone else involved in, or affected by the work, in accordance with industry guidance and organisational procedures
11. confirm that appropriate personal protective equipment (PPE) for the work to be carried out is worn at all times
12. select, prepare, use, maintain and store the tools and equipment required safely, in accordance with the relevant legal requirements and manufacturer’s instructions
13. confirm all equipment has been checked, tested where required, and is fit for purpose, in accordance with the relevant legal requirements and manufacturer's instructions
14. maintain the safety and security of tools and equipment on site
15. carry out the required work in accordance with the information provided and organisational procedures
16. select and use access and positioning methods appropriate to the assessed risks and information provided
17. calculate the expected loads the rigging needs to take, within its design/safety factors and select compatible components to make up the rigging system
18. assess the position and select anchor points for rigging components taking into account the expected load, ground workers, other anchor points, access equipment position, planned drop zone and processing area
19. remove tree sections that can be lowered down using suitable cuts, minimising shock loading in the rigging system
20. confirm arisings are removed and dealt with in accordance with the legal and organisational requirements
21. minimise damage or disturbance to the site and surrounding area while carrying out this work, and confirm that the site is left in a safe and tidy condition
22. implement best practice approaches to sustainability that are appropriate for the work being carried out
23. deal effectively with issues that arise within the scope and limitations of your responsibility, and report issues which cannot be resolved in accordance with organisational procedures
24. complete and store all relevant documentation in accordance with the legal and organisational requirements

1. how to identify and access information relevant to the required work
2. how to identify tree species and families and how species, condition and the time of year will affect treework
3. how to identify hazards and assess the risks associated with the site and the work to be carried out, and the importance of site-specific risk assessment and control measures that are appropriate for your area of work
4. the importance of checking for signs of disease, defects and decay in the tree being worked on and where to obtain professional advice when required
5. the relevant health and safety procedures and Safe Systems of Work (SSoW)
6. the emergency planning and procedures relevant to the site, risk zone distances and the management of risk zones
7. the importance of risk zone management, the correct use of warning signs and barriers to inform and protect others while the work is carried out and the procedures for temporary traffic management, where required
8. the current legislation and codes of practice, industry standards and guidance, organisational policies, procedures and protocols, business and professional ethics that are relevant to your area of work, and to which you must adhere
9. the legal, industry and organisational requirements for training, experience and certification to undertake the work activities required and the importance of acknowledging your limitations and not undertaking work that is beyond your level of competence
10. why it is important to maintain effective communication with other workers and anyone else involved in, or affected by, the work and the methods of communication that should be used
11. the tools, equipment and personal protective equipment (PPE) required for the work and how to safely, prepare, use, carry out operator maintenance, and store these, in accordance with the relevant legal requirements, manufacturer’s instructions, and organisational procedures
12. the legal requirements for checking and testing equipment and the evidence required to show that this has been done
13. technology used within your area of work and how to use it
14. the importance of using a personal fall protection system when climbing and working in trees
15. when tree rigging would be required and its limitations
16. how, when and where to use compound or complex rigging systems
17. how to install and use pull/tag line to aid the removal of sections.
18. how to calculate the expected loads generated by the rigging operation
19. how to select compatible components to make up a rigging system appropriate for the expected load
20. how to select suitable anchor points for the expected loads without compromising the workers’ access position
21. how to select the suitable access position and the planned drop zones
22. how to plan and lay out the rigging site on the ground to safeguard the ground workers, aid workflow, deal with the arisings and place the desired drop zones
23. how to remove tree sections that can be lowered down by using suitable cuts, minimising shock loading in the rigging system
24. the correct methods of dealing with arisings in accordance with legal and organisational requirements
25. the potential impact of the work on the site and surrounding area and how this can be minimised
26. your and the organisation’s responsibility for protecting the environment and working sustainably
27. the importance of checking that completed work meets requirements, in accordance with the information provided
28. the issues that can occur when carrying out aerial tree rigging, the actions to take and the organisational procedures for reporting issues that cannot be resolved
29. the scope and limitations of your competence, responsibilities and accountability
30. the legal and organisational requirements for the completion and storage of documentation

Different methods of dealing with arisings include: burning, stacking, burying, spreading, further processing, re-using as other products

Banksman/signaller – a trained and competent person who controls the movements of machinery, procedures and people on a site, to ensure work activities are carried out safely.

A hierarchy of controls must be established between the banksman/signaller and other operators to ensure that pre-agreed signals are clearly transmitted and understood.

Compound/complex rigging systems:
• drift line
• load transfer
• balance
• cradle
• spider leg
• speedline/skyline
• fake anchor points
• craning and lifting techniques
• crane removal

Drop zone – the designated area into which objects such as tree branches or trunk sections are to be dropped when carrying out aerial tree pruning.

Health and safety risks from chainsaw use:
• being cut by the saw
• hit or crushed by moving timber
• noise-induced hearing loss
• hand-arm vibration (HAV)
• exhaust fumes from petrol-driven chainsaws
• exposure to oils
• effects of fatigue/dehydration on the ability to work safely
• other work equipment or activities on site

Information required to carry out work activities could include:
• drawings
• plans
• schedules
• specifications
• method statements
• Standard Operating Procedures (SOPs)
• manufacturer’s instructions
• customer requirements
• quality assurance requirements
• industry standards (e.g. British Standards)
• verbal or written instructions
• industry guidance (e.g. FISA)

Organisational procedures – refer to procedures set by the organisation you are employed by or the organisation that you are doing the work on behalf of (the client or customer)

Personal Fall Protection System – a collection of components which, when used correctly, combine to prevent a fall. Personal fall protection systems comprise a primary system and a back-up which is attached to an independent anchor wherever possible. The back-up can only be omitted when:
• It is not practical to maintain it for the specific, “stationary” and short-duration task of rope advance/changeover, reinstating the backup as soon as possible
• Carrying out the rescue of a casualty where speed is crucial

Risk zone – Also referred to as Danger zone and Exclusion zone. The Risk zone should be established before commencement of any tree work.

Safe System of Work (SSoW) – is a method of work that puts in place control measures arising from a risk assessment, in order to manage identified hazards, which are broken down into four elements: safe person; safe equipment; safe place; and safe practice.