Tower crane safety
Technical information for tower crane owners and operators that includes two safety alerts with links to the relevant codes of practice, guides and Australian standards.
6. Key messages on tower cranes
The following key messages to industry were identified by the investigation and subsequent verification project following the November 2012 crane fire at Broadway in Sydney. They are most relevant to tower crane manufacturers and suppliers, however may also help crane crews or persons with management or control of tower cranes to work with crane companies to address site issues.
Service (maintenance) intervals
Service intervals, as defined by the manufacturer should be followed.
The system used should include:
- identifying the manufacturer’s requirements
- scheduling and resourcing to ensure that the manufacturer’s requirements are met
- proactive processes to ensure that intervals are met include:
- manufacturer’s maintenance schedules
- receipt of logbook copies
- electronic back to base reporting systems
- incorporated into the build schedule of the principal contractor
- audits to confirm compliance with the service intervals and related service requirements
- proactive processes to ensure that intervals are met include:
- reducing the service intervals where the root cause analysis, see below, identifies that the service intervals are inadequate, eg considering the life of components and the crane’s breakdown history.
Principal contractors (hirers) and crane companies (suppliers) have a joint legislated obligation to consult, cooperate and communicate in matters where they have joint responsibility, which would include ensuring this servicing occurs.
Documentation and record keeping should be improved to better meet the needs of the various parties, eg:
- to advise the operator that an issue identified by the operator and entered into the logbook has been rectified, eg by noting in the logbook with a reference to the service docket number
- to enable to crane company to identify trends, by providing sufficient detail of the issue rectified, and stored in a way to facilitate review
- to enable the principal contractor to reschedule time in the construction program for the next service when a service was conducted along with a breakdown call out.
- to be systematic, referenced and assist with traceability (for example, a certificate of compliance with major inspection to reference relevant reports it relies on, or, erection sign off to reference accompanying documentation such as slew ring NDT report).
Operator’s logbook (crane checklists)
Operator’s Logbook systems are a part of ensuring safe crane use.
The logbook should:
- form part of the induction process for the operator
- be relevant for the specific crane
- be accurately completed by the operator, with site arrangements allowing adequate time for the inspection before commencing lifting each day
- have information from it supplied to the crane supply company, eg sending a copy of the daily inspection checklist page
- be a closed system with issues closed off (sign-off by mechanical servicing staff or by reference to specific servicing document)
- any issue not closed off must be raised with the operator
- be verified/audited as a part of the crane supplier’s systems
- be verified/audited as a part of the hirer’s systems.
Operator induction and assessment of competence
Operator induction and assessment of competence should be conducted by a person(s) competent in use of the crane and site procedures, and may include:
- a handover pack (daily, and more detailed inspection check lists)
- sighting of the operator’s tower crane high risk work licence
- practical induction on the features and controls on the crane, including supervised use by the operator
- information on processes for operator performed maintenance, if any, and procedures to arrange crane servicing, both routine and breakdown
- confirmation of logbook processes
- confirmation of delegations, ie to what level can an operator make decisions, for example can the operator make a call that a hydraulic leak is minor, or are they to contact and discuss with the crane company
- crane evacuation procedures for the site
- record induction, signed by provider(s) and the operator.
Where there is no-one on site familiar with the specific crane it would be expected that the crane company be involved in inducting the first operator.
The crane company should be advised when a new crane operator commences.
A person from the hiring entity (usually the principal contractor) should be nominated as the crane supervisor.
This person should:
- be the main contact between the crane company and the hirer, including reviewing and on-forwarding of the operator logbook information
- have an understanding of safe crane operation requirements, including site arrangements for servicing and recording of log book information
- coordinate the response to issues with the crane
- coordinate and receive sign-off for crane after-maintenance
- coordinate servicing times and breakdown maintenance, and
- have the authority to take the crane out of service, whether due to a fault, weather conditions or to allow for scheduled servicing.
Principal contractor responsibilities
Principal contractors have legal obligations as principal contractors and also as a PCBU with joint responsibility for the crane.
To comply with those obligations they should:
- incorporate maintenance into the build program, considering the need to allow for cool down time between operating and servicing, any curfew restrictions on the site and whether for safety the maintenance needs to be conducted during daylight hours
- provide site personnel and services required for health and safety of service crew, eg crane crew for crane operation, plus if out of normal site hours, builder’s hoist operator and security for access and maintain lighting for access and amenities
- ensure induction of crane operators in the crane supplier’s systems and associated sign-offs, site systems including reporting of crane information and crane evacuation procedures
- incorporate tower crane reviews into safety systems
- audit documentation
- have the operator provide confirmation against general safety audits (for example, provide photos of house-keeping, materials storage, flammable liquids storage, also provide daily/weekly/monthly checks)
Emergency planning / emergency response
Emergency planning for the site must include a response to issues with tower cranes. The plan should include:
- identification of risks (load fall, component loss, jib collapse, tower collapse)
- identification of construction zones and public zones potentially at risk
- evacuation plan for construction zones
- notification contact details for public zones for example, in the CBD, a consultative approach with near neighbours and respective fire warden may be required
- a system of putting emergency services in direct contact with specialist crane staff (crane supplier, crane engineers, etc), and
- when necessary, principal contractors should also liaise with emergency services regarding their emergency preparedness and plan.
There have been many advances in technology over the years that now provide reasonably practicable means to control risks better than when many of the tower cranes were manufactured. Improvements in technology should be considered for retrofitting in older cranes. Some are now considered mandatory in new cranes.
These advances include the features specified in Australian Standard AS1418.4 and the following:
- data logging systems to better understand the crane usage, utilisation and load spectrum, and therefore remaining life of structural and mechanical components
- remote monitoring to assist with identification of unsafe operation, defect identification and more direct planning of servicing. Available for real time monitoring, delayed reporting or instant messaging of alarm situations
- anti-collision systems, although not fool proof, provide assistance when more than one crane is sharing the same airspace
- anemometers for better information on wind conditions.
Root cause analysis
Crane companies should have systems in place to review similar and reoccurring faults. Crane companies should identify why parts are failing and if maintenance needs to extend beyond fixing the immediate failed part. This analysis would include:
- analysing trends; investigation of failures to determine root cause
- ensuring that the service schedule was/is being completed as planned
- a review to determine if the service regime and schedules are appropriate, and
- if the service regime or schedule is not appropriate, amend as necessary.
This analysis should include consideration of industry trends, known incidents, service bulletins and alerts issued by manufacturers and other information sources to identify factors that influence the service life of components.
The designer / manufacturer should also be informed, to provide them information that may assist them in identifying trends and therefore, if appropriate, addressing the issue more globally.
Design changes (alterations)
When a design change occurs, that may affect health and safety of a tower crane, the legislated design alteration process must be followed:
- the new design should be documented
- a Design Compliance Statement must be obtained from the designer of the alteration
- a Design Verification Statement must be issued from an independent verifier, following verification of the alteration
- the altered design must be Design Registered with a WHS regulator.
- changes in engines, drives, brake systems, control systems, boom sections and the like where the new component is not simply a like-for-like replacement,
- the addition of signage with greater wind area or mass, or in a different location, than allowed for in the crane design. The legislated process does not apply to the site design matters of footings and ties, although steps 1 & 2 should be followed, and
- the use of tower sections other than those considered in the crane design and the design of transition sections to accommodate such usage.
WorkCover’s position is that this process must be followed for any design alteration that has already occurred or future design alterations that have the potential to affect health and safety.
The message is particularly important given the age of some tower cranes.
Fire extinguishing equipment
Fire extinguishers appropriate for the potential fire risk, during both operation and maintenance, should be provided in appropriate locations for the crane operator and maintenance personnel and consider the working location of the people and possible fire sources.
Fire prevention / suppression
- separating potential fuel sources from potential ignitions sources, eg
- relocating hoses or other fuel sources away from ignition sources
- providing guarding to separate flammables from ignition sources
- lagging of hot components such as exhausts
- adequacy of fire fighting equipment
- fire detection or engine compartment monitoring, to allow for early intervention
- practicability of installing a fire suppression system.
The risk of a fall must be managed in accordance with the hierarchy of control which requires using engineering, isolation and substitution controls in favour of administrative controls such as fall arrest systems.
Information on the risk of falls and control measures to be used must be passed down the supply chain.
Where the risk is managed by the use of a fall arrest system, emergency procedures, including rescue procedures, must be established and tested so that they are effective.
Industry plant consultative committee comprising WorkCover, the Master Builders Association of NSW and the Construction, Forestry, Mining and Energy Union.