Draft guidelines for use of gels on the Defence Estate
1.1
Selection/Approval of Gels for use on the Defence Estate
Gels/ Water enhancers which are currently endorsed for use in Australia by AFAC are USDA approved
chemicals. A complete list of gels which have been approved according to USDA Forest Services
Specification 5100-306a is given in Appendix F. Gels in this list are evaluated and approved only
according to specified mix ratios and as such should only be applied in compliance with
recommendations.
Approved products on the list include both coloured and uncoloured gel products. Uncoloured products
involve only the addition of a single concentrate with water while coloured products may require the
addition of one or two components, that is, a gel and a qualified colourant (USDA, 2010a). Approved
colourants must be significantly different to colours used for long-term retardants. The highest approved
mix for an uncoloured product is no greater than 3 per cent due to the difficulty in observing where the
gel has been applied (USDA, 2010a). The gel viscosity of the lowest mix ratio prepared with room
temperature, deionised water is required to be at least 200 centipoise (cP).
Ingredients which are unacceptable for use in gel products according to USDA Specification 5100-306a
include:

Sodium ferrocyanide (Yellow Prussiate of Soda or YPS)

Dichromates

Thiourea

Borate or other boron-containing compounds

Polychlorinated biphenols (PCB)

Polybrominated diphenyl ethers (PBDE)
Presently the NSW Rural Fire Service (NSW RFS), VIC Country Fire Authority (VIC CFA), ACT Rural
Fire Service (ACT RFS) and WA Fire and Emergency Services Authority (WA FESA) are not using gels
operationally. The NSW RFS, VIC CFA and ACT RFS are currently trialling the effectiveness of gel
products to determine beneficial uses. WA FESA is not considering the introduction of gels for fire
suppression at present. According to the OEH (2011) ‘Thermo-Gel’ and ‘Phos-Check AquaGel’ are the
two water enhancers currently approved for use, with gel to be used as an alternative to foam in
conditions of hot, dry weather where foam may dry out quickly.
1.2
Safe Storage of Gels
In order to meet USDA specification 5100-306a wet and dry gel concentrates must be able to be stored
outdoors for 52 weeks, with no separation of particles larger than 0.625 cm (USDA, 2010a). Dry
concentrates are not to show any signs of caking with outdoor storage. Mixed concentrates are required
to be stable for a period of 14 days with no visible sign of microbial contamination, discolouration or other
changes in appearance (USDA, 2010a). In determining outdoor stability, wet and dry concentrates are
subject to temperature and weather cycles to attempt to mirror typical conditions of exposure. Wet and
dry long term gel concentrates are required to meet guidelines for corrosive behaviour, and must fall
under the maximum allowable limits for corrosion. Specifications require that gel packaging must include
the following information:

The manufacturer's name or trademark

Product identification including formulation codes and production information codes

Volume of concentrate per container

Month and year of production.
The individual storage requirements of gels are detailed in product MSDS sheets. The longevity of gel
products may vary between wet and dry concentrates with dry compounds able to be stored for long
periods without degradation subject to the provision of a clean, UV protected storage container which is
kept away from direct heat (SAU Victoria, 2010). Wet gel concentrates such as Thermo-Gel are
guaranteed for three years after the date of purchase and may be effective for 7–8 years if agitated every
six months (Forest Systems, 2012).
It is recommended that that best practice guidelines for storage of chemical products should be followed
to maximise product effectiveness and long term viability. These guidelines include:

Keep products in original containers to allow for an accurate stocktake of available chemicals (some
metals may be affected by wet gel concentrates)

Chemicals should be kept tightly closed when not in use

Store chemicals upright

Chemicals should be kept in an enclosed, secure environment to prevent unauthorised access

Storage conditions should have impervious flooring and good ventilation

Chemicals should not be exposed to direct sunlight, and ideally should be stored above freezing and
below 40°C

Wet chemical concentrates should not be stored above dry concentrates

Chemical storage should be at a suitable distance from other buildings, watercourses and drains. No
spillage should be allowed in to sewers/drains or watercourses.
Adherence to storage standards will minimise the risk of a potentially hazardous chemical incidents.
Where a gel is introduced on the Defence Estate the product should be registered in the CHEMALERT
system (Defence inventory system).
1.3
Handling and use of Gels
1.3.1
Health and Safety Considerations
Wet and dry gel concentrates are required to meet standards for acute oral toxicity, acute dermal toxicity,
eye and dermal irritation classifications, and mammalian and fish toxicity levels. In studies undertaken by
the USDA Forestry Service, only product concentrates were deemed to induce some level or eye
irritation with Chemdal Aqua Shield 100 and Barricade II concentrated gel products reported as
moderately irritating to eyes (USDA, 2008). It is therefore suggested that suitable personal protection
equipment (PPE) and safe handling procedures should be followed when handling these concentrated
products (USDA, 2007a). Wildfire AFG Firewall, Wildfire AFG Firewall II and BioCentral Blazetamer 380
had the highest skin primary irritation indexes of 2.2, 1.1 and 1.1 respectively in handling of concentrated
products (USDA, 2008). Despite these indexes being larger than the values obtained for all other gel
products, the ‘greater’ values are classified as a low level irritant as the index falls below the standard of
5.0 whereby PPE and safe handling procedures are required (USDA, 2007a).
A health assessment risk was undertaken by Labat-Anderson (2003) and following the assessment it
was determined that the greatest level of risk to use of gels was through accidental spills where public
exposure occurred. In all other instances of exposure to gels, that is, through use by fire fighting crew
members including engine crews, overhead workers, helitack crews and smoke jumpers the risk quotient
was less than 0.01 indicating a very minor risk to fire fighters and no need for mitigation of risk to occur. It
should be noted that these risk assessments were undertaken considering only two gel products, FireOut
ICE and Stockhausen Firecape FP-47, the latter of which is no longer on the USDA QPL for gels. As
such an updated assessment of risk may need to occur to consider the currently available gel products.
To enable safe handling of gel products it is a requirement that each product is accompanied by a MSDS
detailing health hazards associated with gel use and recommended procedures for handling. Instructions
for handling of chemicals should be closely followed to avoid any adverse chemical reaction associated
with gel contact.
It is recommended that wherever bushfire chemicals are handled a first aid kit including an eye wash unit
should be readily available.
Eyes: It is recommended that all gels should avoid eye contact to avoid any irritation, pain and redness.
Where contact occurs, eyelids should be held apart and the eye flushed continuously for a period of at
least 15 minutes (Forest Systems, 2008). To prevent eye contact splash-proof goggles should be worn
during handling and use.
Inhalation: Is a low irritant, however over exposure may result in mucous membrane irritation of the
nose and throat and coughing (Forest Systems, 2008). To avoid exposure natural or mechanical
ventilation should be provided in storage and mixing areas, with vapour levels maintained below
recommended exposure standards. It is recommended that breathing should be protected where
quantities are decanted without sufficient ventilation e.g. a type A (organic vapour) respirator. (ICL
Performance Products, 2009; Forest Systems, 2008). During use firefighters should be equipped with
self-contained breathing apparatus.
Skin: All direct skin contact should be avoided as contact may result in irritation. Where contact occurs
skin should be thoroughly washed with soap and water, and should irritation persist it is important to seek
medical attention. Neoprene, rubber or PVC gloves and closed work clothing e.g. coveralls and boots
should be worn when coming in to contact with the chemical (ICL Performance Products, 2009; Forest
Systems, 2008). All contaminated clothing should be discarded or washed prior to reuse.
Ingestion: Low toxicity levels however ingestion of large doses may cause nausea, vomiting, abdominal
pain, diarrhoea and drowsiness (Forest Systems, 2008). If ingestion occurs do not induce vomiting.
Provide water immediately to rinse the mouth, continue drinking water and seek immediate medical
attention.
1.3.2
Chemical use and mixing
There are several gel products which are approved for use according to the USDA QPL. To determine
the gel products which are most suitable for use on the Defence Estate, it is important to consider factors
relating to mixing requirements and clean up requirements. Dry concentrates can by mixed via in-line
induction or circulation e.g. a mobile hydroseeder, while gel concentrates require an in-line flow mixer
such as a FireDos® water driven proportioner (SAU Victoria, 2009). It is critical that mix ratios are strictly
adhered to as exceeding the mix ratio may cause the gel product to clog equipment (USDA, 2009c). The
amount of water required to mix a gel product is dependent on water quality, with a greater mix ratio
required when hard water is used in comparison to soft water (USDA, 2009a). Salt water cannot be used
as a medium for mixing of gels.
Gels are typically applied from helicopters, single engine airtankers (SEATs) and/or ground equipment.
However products may have specific uses and may not be compatible with all drop systems, as such
suitability for use with given fire-fighting equipment should be checked prior to use.
It is recommended that all equipment should be thoroughly rinsed at the end of each day to minimise
potential impacts caused by erosion. All rinse water generated within this process should be treated as
contaminated and disposed of appropriately (USDA, 2009). This is also critical to ensure that there are
no residuals amounts of retardant, as retardant can cause an entire batch of gel to break down and
become non-viable (USDA, 2009). Mixing of gels with foam products should be avoided as many are
incompatible (USDA, 2009).
1.4
Operating procedures to avoid or minimise adverse environmental impact of
Gels
Given that several fire authorities are only at the point of trialling gel products and do not use gels as an
operationally approved fire suppression tool it is recommended that gels should not be adopted for use
by the Defence Estate at the current time. It is suggested that this position should be reconsidered at a
later date following sufficient trials within an Australian environmental context, as the ability to use gels to
safeguard structural assets could be highly valuable for Defence purposes. If approved for use in the
future the implementation of following procedures on Defence estate can assist in reducing the
environmental risk:

Should gels be adopted for use on the Defence Estate, it is suggested that a 100 metre buffer zone
is implemented when applying gels around waterways and known incidents of susceptible threatened
biota including fish and frogs. While the environmental impacts of gels are not fully understood,
particularly in comparison to recognised effects caused by retardants and foams, it is recognised that
all gel products are toxic to fish and aquatic life at some scale (USDA, 2009a). The NSW OEH apply
a precautionary 100 m buffer zone around waterways and aquatic environments for implemented on
NSW National Parks (OEH 2011).

A reporting process should be implemented to facilitate the auditing of incidents of gel applications
within 100 m buffer zones. A sample reporting template which is currently implemented by the USDA
is provided in Appendix C and could be tailored to the needs of Defence Estate to avoid any
unnecessary process.

Use and storage of gels is in accordance with the product specific MSDS, noting the longevity and
stability varies significantly between manufacturers (See Section 1.2).
REFERENCES
Forest Systems Pty Ltd (2008). Thermo-Gel® 200L Material Safety Data Sheet.
Forest Systems Pty Ltd (2012). Thermo-Gel® 200L Frequently Asked Questions. [Accessed 29-5-12,
http://www.thermogel.com.au/commGel.php].
ICL Performance Products (2009). PHOS-CHEK® AquaGel-K Material Safety Data Sheet.
Labat-Anderson Inc (2003). Human Health Risk Assessment: Wildland Fire-Fighting Chemicals. Report
Prepared for Missoula Technology and Development Centre, USDA Forest Service.
Office of Environment and Heritage (OEH) (2011). Fire Management Manual: Policy and procedures for
fire management.
State Aircraft Unit Victoria (2010). Inno Word: Initial field assessment [of] super absorbent polymers
(SAP/s)- October 2009. Vol. 5. [Accessed 29-5-12,
http://dsewebapps.dse.vic.gov.au/fires/updates/report/sau/SAU_External/documents/innovation/005%20I
nno%20Word%202010%20SAP-Gels.pdf].
United States Department of Agriculture (2007a). Specification 5100-306a. Specification for Water
Enhancers (Gels) for Wildland Firefighting
United States Department of Agriculture (2008). Mammalian Toxicity. [Accessed 29-5-12,
http://www.fs.fed.us/rm/fire/wfcs/performance/documents/MamTox_WE_043010.pdf].
United States Department of Agriculture (2009). Wildland Fire Chemicals Systems: Tactics and Product
Characteristics Aerial Application. [Accessed 28-5-12, http://www.fs.fed.us/rm/fire/wfcs/index.htm]
United States Department of Agriculture (2009a). Wildland Fire Fighting: Chemical Products. [Accessed
28-5-12, http://www.fs.fed.us/rm/fire/wfcs/index.htm]
United States Department of Agriculture (2009c). Wildland Fire Chemicals Systems: Tactics and Product
Characteristics Ground Application. [Accessed 28-5-12, http://www.fs.fed.us/rm/fire/wfcs/index.htm]
United States Department of Agriculture (2010a). Specification 5100-307a. Specification for Fire
Suppressant Foam for Wildland Firefighting (Class A Foam).