Chainsaws and tree felling continue to kill
Several terrible injuries including fatalities have occurred during tree felling and chainsaw use.
The following key lessons may help save your life.
Initial site survey:
Wherever possible, assess jobs in advance. This allows for correct selection of equipment, allocation of staff and prior knowledge of hazards. It also allows an experienced site surveyor to provide guidance and work methodology to the people carrying out the work.
Risk assessment/emergency planning:
The assessment should take account of the hazards that are relevant and specific to the given site, task and tree. It is not just an exercise on paper; if you cannot control risks to acceptable levels, work on that task must not proceed until suitable arrangements are in place. Emergency contingency plans (first aid, emergency contact numbers, Accident and Emergency number, site location etc) must be made in advance.
Work planning:
All information, as well as the actual undertaking of the job, must be planned, agreed and understood by all the team.
Felling cuts:
Effective control of the fell is maintained by an appropriate combination of the directional or sink cut, hinge and main felling or back cut. Felling cuts must be appropriate to the tree size and form and consistently accurate.
Felling aids (breaker bars, wedges etc):
These must be appropriate to the tree size and form. The need for felling aids must be identified in advance; they must be appropriate and readily available to the person undertaking the fell.
Control lines, pull ropes, anchor ropes, winches etc:
If these types of system are to be used there should be clear understanding of their intended purpose and suitability for the task, eg is it:
- An assisted fell?
- An anchor or back up?
- A felling aid?
- A winching operation? or
- A combination of tasks?
Avoid:
'Free hand' pulling or non-anchored applications. There is a high risk that if the person pulling the rope sways or rocks the tree during the felling operation, the main felling cut at the rear of the tree will open and close with the risk that the chainsaw operator could compromise the integrity of the hinge.
Do not:
Over tension lines, as this may place considerable tension on the rear of the tree which may cause the hinge to sever prematurely, the tree to split, and injury to the chainsaw operator.
Avoid:
Making the main felling or back cut while your workmate is simultaneously applying tension to the line. As well as the above risks, the chainsaw operator cannot safely place the back cut and monitor the action of his colleague operating the line. In the majority of cases the tree feller should be able to form the back cut, leave a hinge of appropriate size, step into a safe area, and then issue an agreed signal for the person on the lines to start operation.
Escape routes:
Plan escape routes in advance – they must be clear of obstructions. If control is lost over the fell, use the escape route and try not to turn your back on the falling tree. Remember, accidents often happen because unforeseen or remote risks actually materialise. Consider the possibility that the tree may fall towards your intended escape routes. Have you got enough back up to ensure that the tree will fall in the intended direction? Is there enough space to enable you to take evasive action if the unforeseen does occur?
Staff competency and experience:
Staff should have the necessary training, experience and competency certificate relevant to the task they are undertaking. Remember that people holding only CS 30/31 with little additional experience can quickly find themselves in situations outside their experience and skill base. This is particularly true when faced with larger and awkward fells and when faced with the unique hazards associated with arboricultural operations in gardens and the built