Application
This unit of competency describes the skills and knowledge required to select, check and install rigging systems to support aerial tree work for the controlled descent of loads to drop zone. This unit does not cover crane operations.
The unit applies to individuals working in a broad range of arboriculture contexts who undertake defined routine activities under supervision. They exercise limited autonomy within established and well known parameters, providing solutions to a limited range of predictable problems.
The arboriculture industry requires that all ground-based tree rigging work is undertaken according to preferred industry practices (as outlined in the Companion Volume).
Legislation, regulations and by-laws relating to the treatment and removal of trees apply in some states and territories.
Elements and Performance Criteria
Elements | Performance Criteria |
1. Assist in preparation of work site | 1.1 Confirm work instructions and location of worksite with supervisor 1.2 Confirm workplace health and safety hazards and controls in job safety analysis (JSA) with supervisor 1.3 Confirm availability of first aid and emergency personnel, equipment and procedures |
2. Prepare for rigging | 2.1 Identify tree defects and contribute to tree assessment process 2.2 Discuss and confirm rigging method with work team 2.3 Confirm rigging method complies with identified risk controls with supervisor 2.4 Select rigging equipment and check for defects, removing defective equipment from service 2.5 Select, check and use personal protective equipment |
3. Perform rigging operations | 3.1 Communicate with work team during operations according to work site and environmental conditions, using methods agreed with work team 3.2 Tie, dress, set and finish rigging knots and hitches according to rigging system requirements 3.3 Monitor rigging system, work team movements and environmental conditions to ensure safe working conditions 3.4 Control load to drop zone and adjust rigging according to aerial worker directions 3.5 Disconnect load from rigging system 3.6 Re-check rigging equipment components for defects, and remove defective equipment from service 3.7 Return rigging components to aerial work team |
4. Complete rigging operations | 4.1 Confirm completed rigging operations with aerial work team 4.2 Remove and dismantle rigging system from tree 4.3 Clean, check and store tools, equipment and machinery according to workplace procedures 4.4 Report and tag defective tools and equipment 4.5 Clean and store personal protective equipment 4.6 Record and report rigging operation outcomes according to workplace procedures |
Evidence of Performance
An individual demonstrating competency must satisfy all of the elements and performance criteria in this unit.
There must be evidence that the individual has installed rigging equipment and controlled at least six loads from an aerial location to the drop zone using ropes, knots and rigging system appropriate for the load dimensions and mass.
There must also be evidence that the individual has:
confirmed work instructions and location of worksite
identified site hazards, assessed risks and confirmed controls with supervisor including:
selected, checked and used appropriate personal protective equipment
confirmed the availability of first aid and emergency equipment, personnel and procedures
implemented workplace health, safety, environmental and traffic control measures
contributed to tree assessment process by assessing trees for defects
checked and removed defective equipment from service
monitored rigging system, work team movements and environmental conditions for safe work conditions
communicated with work team and discussed and confirmed rigging method and rigging equipment during operations using agreed communications methods
tied, dressed, set and finished arborist knots according to rigging task, including demonstrating the following knots:
alpine butterfly knot
bowline on the bight
cow hitch with better half
clove hitch and two half hitches
half hitch pre-knot
klemheist friction knot
marline pre-knot
marline spike hitch
riggers knot and two half hitches
running bowline
sheet bend
slippery sheet bend
timber hitch
zeppelin bend
controlled load to drop zone, adjusting rigging according to aerial worker instructions and disconnected load from rigging system
returned rigging components to aerial work team after checking components for defects
confirmed completion of rigging operation with aerial work team and removed and dismantled rigging system including:
cleaned, checked and stored tools and equipment from worksite
reported and tagged defective tools and equipment
recorded and reported rigging outcomes according to workplace procedures.
All ground-based tree rigging work is required to be performed according to preferred industry practices (as outlined in the Companion Volume).
Evidence of Knowledge
An individual must be able to demonstrate the knowledge required to perform the tasks outlined in the elements and performance criteria of this unit. This includes knowledge of:
current industry practices (as outlined in the Companion Volume) for ground-based tree rigging work and tree dismantling
safe operations in ground-based rigging, including:
first aid, emergency personnel, equipment and procedures
workplace health, safety, site, environmental and traffic control measures
identification of ground-based hazards
above ground hazards and risk
personal protective equipment
monitoring the safety of working conditions
procedures for tree assessment before rigging operations, including tree examination for tree defects
ground-based rigging procedures and practices, including:
rigging equipment and its performance
rigging methods and rigging systems
examination of rigging equipment for defects, and procedures to manage defective equipment
assembling and installing rigging equipment
checking rigging equipment
tying, dressing, setting and finishing arborist knots for rigging
communications strategies used in arboriculture, including:
voice
hand
whistle signals
electronic communications
communications specific to the rigging task
techniques for controlling, raising, lowering and redirecting loads, including balancing load on centre of gravity
cleaning, storing and maintaining tools and equipment
records and reporting procedures for rigging operations.
Assessment Conditions
Assessment of the skills in this unit of competency must take place under the following conditions:
physical conditions:
worksite with aerial tree operations or environment that accurately represents workplace conditions
resources, equipment and materials:
rigging equipment
static and dynamic rope systems
harnesses
lowering and friction devices
high decibel whistle
personal protective equipment
first aid and emergency kit
rescue kit
specifications:
access to current preferred industry practices (as outlined in the Companion Volume) for ground-based tree rigging work and tree dismantling
workplace and manufacturer instructions for safe operation of rigging equipment
relationships:
supervisor and aerial work team.
Assessors of this unit must satisfy the requirements for assessors in applicable vocational education and training legislation, frameworks and/or standards. In particular, assessors must have:
arboriculture vocational competencies at least to the level being assessed
current arboriculture industry skills directly relevant to the unit of competency being assessed.
Foundation Skills
Skill | Description |
Writing | Complete reports and records using clear language and industry terminology to ensure clarity of meaning |
Oral communication | Use open and closed questions logically to clarify work instructions Use industry terminology to communicate with team members |
Get the Work Done | Respond to routine problems using step-by-step procedures when safely setting and preparing rigging and checking and maintaining rigging equipment |
Sectors
Arboriculture (ARB)