This safety alert reminds people of the fire hazards associated with containment netting or equivalent used in the construction industry, and the measures that should be implemented to control the associated risks.
Containment netting may also be referred to as ‘containment sheeting’, ‘screening’ or ‘scaffolding mesh’.
Recently a serious fire developed on a building remediation site when containment netting fixed to multi-storey scaffolding ignited. The fire resulted in the deployment of emergency services and required the evacuation of personnel from the work site and building.
The containment netting involved in the incident was manufactured from polyurethane (PE) with fiberglass re-enforced banding. A fire retardance substance was not included in its manufacture. Whilst fire hazard properties have not been tested, it has been observed that the material is highly flammable.
This is the third incident this year where polymer containment netting has ignited on a construction or demolition site.
Many materials and substances found in workplaces are flammable or combustible. The risks associated with a certain material or substance may not be immediately obvious. Subsequently, independent testing of building materials for fire hazard properties is required to appropriately assess and control the risks.
There is no current Australian standard or industry guidance that prescribes acceptable performance criteria for the flammability of containment netting / sheeting.
Action required by suppliers
Suppliers of containment netting have specific duties under Work Health and Safety legislation, including:
- a supplier must ensure, so far as is reasonably practicable, the containment netting is supplied without risks to the health and safety to persons who work with the containment netting, or persons whose health and safety may be affected by the use of the containment netting.
- a supplier must carry out, or arrange the carrying out of, any calculations, analysis, testing or examination that may be necessary to ensure health and safety e.g. flammability.
- adequate information must be provided when supplying containment netting, including:
- the results of any calculations, analysis, testing or examination, e.g. any flammability properties identified by testing
- the conditions necessary to ensure that the containment netting is without risks to health and safety when used for a purpose for which it was designed or manufactured, e.g. restricting the use of materials to a maximum height
- current, relevant information must also be provided when requested by persons who handle, use, store or dispose of containment netting.
Designers, manufacturers and importers have similar duties.
Action required by principal contractors
The risks associated with fire hazards and containment netting must be managed, so far as is reasonably practicable, by ensuring:
- work undertaken in proximity to the containment netting does not use possible ignition sources without appropriate protection e.g. shields for hot works
- combustible materials are not stored in proximity to containment netting
- the containment netting used on site is manufactured from material of low fire hazard properties, or includes measures incorporated in its manufacture to control the risks associated with fire.
- uncontrolled or unauthorised access to the containment netting is eliminated or minimised
- emergency systems, including evacuation procedures, are in place, and are regularly tested
- all site personnel and contractors are informed of the fire hazards associated with containment netting during the induction process, and are trained in emergency procedures
To manage the risks associated with fire hazards and containment netting, Principal Contractors should request information from the supplier regarding fire hazard properties, including:
- the results of ignitability, flame propagation, flammability, or smoke release testing and analysis
- the measures included within the design and manufacture of the containment netting to control fire hazards, e.g. fire retardation substances
- the conditions necessary to eliminate or minimise any residual risk associated with fire hazards and the containment netting.
When selecting which product to be used, consideration should be given to the inherent risks associated with the site. Sites with a high risk may require products with very low fire hazard properties.
Until an Australian standard or industry guidance is developed and published that prescribes acceptable performance criteria, suppliers of containment netting should provide information on fire hazard properties including:
- demonstrating compliance with Loss Prevention Standard 1215 or British Standard 7955:1999 (or equivalent standard that prescribes the same test and performance criteria), or
- demonstrating compliance with NFPA 701: Standard Methods of Fire Tests for Flame Propagation of Textiles and Films; or
- providing test results with a flammability index between 0 and 25 (where zero is the least flammable) when tested in accordance with AS 1530.2-1993 Methods for fire tests on building materials, components and structures - Test for flammability of materials, or
- providing test results that demonstrate self-extinguishing and low flame propagation properties.
All tests conducted within Australia should be undertaken by a NATA accredited laboratory.
Alternative products should be sourced, and in-situ products should be removed or replaced as soon as is reasonably practicable, if:
- a supplier cannot provide relevant information in accordance with the performance criteria above; or
- a Principal Contractor is unable to obtain relevant information in accordance with the performance criteria above; or
- the product has fire hazard properties that do not comply with the performance criteria above.
Until the in-situ product is removed or replaced, the risks associated with fire hazards and containment netting must be managed by other means, as outlined above.