Safe Work Australia have recently released a document detailing the safe way to manage the risks associated with felling, trimming or removing trees. Although for years climbing has been the favourable option, this document guides people toward the use of Elevated Work Platforms to ensure a minimised risk of damage, injury or even death. Below is excerpts from the document.
EWPs specifically designed to lift people should be used to access a tree, where reasonably practicable. These minimise hazards like dehydration and fatigue from climbing trees and are designed as a working platform to prevent the worker falling.
Types of EWPs commonly used to access trees for trimming and removal work include:
- Trailer mounted EWPs (see Figure 2)
- Self-propelled EWPs with telescoping boom including knuckle boom (see Figure 3)
- Vehicle mounted EWPs (see Figure 4).
- Trailer mounted EWP
- Self-propelled EWP
- Vehicle mounted EWP
Operators of EWPs should be assessed as competent against the relevant national UoC. As different types of EWP require different competencies to operate, training in the specific type of EWP being considered for the work should be provided.
Note: The use of a boom-type EWP with a boom length of 11 metres or more requires the operator to hold an EWP high risk work licence. The operating crew should consist of at least two workers, with one to remain on the ground as a safety observer or spotter. The nominated ground worker should also be trained in the operation of the lower vehicle-mounted controls to lower the platform in an emergency. A copy of the operator’s manual should be kept with every EWP. Operators should read the manual and be familiar with it before operating the machine. EWPs should be operated according to the manufacturer’s instructions. A pre-start safety check should be carried out on the EWP in accordance with the manufacturer’s instructions to identify damaged or faulty equipment and to ensure the EWP is safe to operate. The safety check should also ensure the emergency descent is functioning correctly. The EWP operator and safety observer should establish an exclusion zone prior to work commencing to ensure pedestrians and others are not entering the danger zone. An appropriately trained safety observer or spotter should be in place to monitor clearances between the operating EWP and overhead electric lines, traffic, adjacent structures or other hazards. The safety observer should have a means of communicating with the EWP operator at all times. The safety observer function should be a designated role. They should not be distracted by carrying out other tasks or duties while the EWP is being used.
Examples of control measures for using an EWP for tree trimming
Control measures for EWP use include:
- Ensuring every person in the EWP wears a full body fall-arrest harness complying with AS/ NZS 1891.1:2007: Industrial fall-arrest systems and devices – Harnesses and ancillary equipment. Harnesses must be attached to the purpose-built anchor points provided on the EWP.
- Checking the location of overhead electric lines before starting work. If overhead electric lines are present the state or territory Electricity Supply Authority or Electricity Regulator should be contacted to find out the extent of the work zones, approach distances and any specific work requirements that apply to working in the vicinity of the overhead electric lines.
- Ensuring the rated capacity of the EWP is not exceeded. The rated capacity includes the weight of the operator, any other person on the platform, tools and branches or other debris.
- Not operating the EWP on gradients that exceed the manufacturer’s instructions and where possible keeping the EWP’s boom on the uphill side of the EWP’s base.
- Ensuring traffic control measures are in place within the established exclusion zone when working on or above roads. All parts of the EWP should remain clear of traffic hazards. Operators should be aware of potential tail or knuckle swing into traffic areas.
- Not using the EWP when wind speeds exceed the manufacturer’s recommendations.
- Ensuring tyres are inflated to the correct pressure in accordance with the manufacturer’s recommendations. This is critical for the stability of EWPs when outriggers are not being used. If outriggers are required for stability they should be engaged before the platform is raised.
- Ensuring ground surface conditions are checked. Soft soil, underground services, tanks, drains and pipes can collapse under the weight of the EWP or outriggers and cause the EWP to tip over.
Suggested controls for working from the EWP include:
- Not positioning the EWP under the branch to be trimmed or removed. The EWP should be located at or above the level of the cut.
- Keeping the platform free of debris and tree off cuts. Hand tools carried within the platform should be secured.
- Ensuring no fuel is carried in the EWP and refuelling is done on the ground outside the EWP cage or bucket.
- Not attaching ropes between the EWP and any part of the tree. An EWP is not to be used as a crane. An independent rope should be used to lower offcuts.
- Wearing PPE e.g. a safety helmet, gloves, eye protection and safety footwear. Chainsaw operators should also wear cut-resistant leg protection and hearing protection.
- Always keeping harnesses attached to the anchor points within the EWP.
- If climbing from the EWP into a tree, the climber should wear a harness suitable for tree climbing and be attached to the tree—having loaded the anchor point—before releasing the anchorage on the EWP.
Further information on the safe use of EWPs is in AS 2550.10-2006: Cranes, hoists and winches – Safe use – Mobile elevating work platforms. Further information on fall-arrest harnesses is in AS/NZS 1891.1:2007: Industrial fall-arrest systems and devices – Harnesses and ancillary equipment and AS/NZS 1891.4:2009: Industrial fall-arrest systems and devices – Selection, use and maintenance.