What Does Biodegradable Actually Mean?
Biodegradable describes a material that breaks down through the action of micro-organisms - bacteria, fungi, or algae. The term is broad. It does not specify a time frame, a temperature, an environment, or an end-product. A plastic bag that fragments into smaller plastic particles over twenty years in a landfill technically qualifies. So does a paper bag that breaks down in six weeks in a backyard compost heap.
In Australia, there is no enforced legal standard behind the word "biodegradable" on bin liners or garbage bags. A manufacturer can print it on the packaging without certification, without testing, and without a guarantee that the bag breaks down in any realistic time frame. This is the heart of the greenwashing problem. A biodegradable bin liner you buy off the shelf may be made from polyethylene with an additive that speeds up fragmentation - sometimes called oxo-degradable - which produces microplastics rather than safe organic matter.
For Melbourne businesses, the practical takeaway is simple. If the label says "biodegradable" without naming a specific Australian standard, treat it the same as a regular plastic bag. It belongs in your general waste bin. It does not belong in a FOGO bin, it cannot be home composted, and it does not earn any sustainability credit in a council audit.
What Does Compostable Mean - and Why the Certification Matters
Compostable bin liners go further. A compostable material breaks down completely into water, carbon dioxide, and biomass - with no toxic residue and no microplastic fragments - within a defined time frame under defined conditions. The "defined" part is what separates compostable from biodegradable. Compostable bags are tested against a published standard before the word can legally be used on certified products.
In Australia, two standards apply. AS 4736 covers industrial composting - the high-temperature commercial facilities that process council green-bin and FOGO collections. AS 5810 covers home composting - the lower-temperature backyard compost bin or worm farm. The standards are not interchangeable. A bag certified to AS 4736 will break down at a commercial composting facility but may not break down completely in a home compost. A bag certified to AS 5810 works in both environments.
For most Melbourne hospitality and aged care operators, AS 4736 is the relevant standard. Council FOGO collections go to industrial composting facilities, so AS 4736 certified bin liners are the compliant choice. The certification is independently verified and the certified products carry a seedling logo or the specific standard number printed on the packaging.
AS 4736 Certified Compostable Bin Liners - What the Standard Means for Your Business
AS 4736 is the Australian Standard for "Biodegradable plastics suitable for composting and other microbial treatment." It is the certification council waste contractors look for when a Melbourne business asks whether a particular liner is FOGO compliant.
The standard tests four things. First, the material must disintegrate within 12 weeks in a commercial composting environment, meaning no fragments larger than 2 millimetres remain in the screened compost. Second, at least 90 per cent of the organic carbon in the material must convert to carbon dioxide within six months - this is the biodegradation test. Third, the resulting compost must support plant growth at the same rate as a control sample, demonstrating no toxicity. Fourth, the material must contain no more than the maximum allowed levels of heavy metals and other regulated contaminants.
Practically, this means an AS 4736 certified bin liner will fully break down inside the industrial composting facility your council contracts with - typically within 90 days at sustained temperatures of 55 to 60 degrees Celsius. The plant-based films used to manufacture these liners (commonly PLA, cornstarch blends, or PBAT polymers) leave no microplastic residue. A bin liner labelled simply "biodegradable" without the AS 4736 reference offers none of these guarantees. For a Melbourne business with a FOGO obligation, the standard number on the packaging is the difference between compliance and contamination.
FOGO Bins and Bin Liner Requirements - What Your Council Actually Needs
FOGO stands for Food Organics and Garden Organics. It is the green-lidded kerbside bin Victorian and NSW councils are progressively rolling out as a mandatory third waste stream. The Victorian Circular Economy Act commits all councils to FOGO services by mid-2027, and many Melbourne metropolitan councils are already operating mandatory FOGO programs for both households and commercial premises above a defined waste-generation threshold.
The single most important rule for FOGO is the bin liner. Council waste contractors will reject a FOGO bin that contains a non-compostable liner because the bag contaminates the entire load at the composting facility. A bag labelled "biodegradable" but not certified to AS 4736 will be picked out at the sorting stage if it is identified, or - worse - will fragment into microplastics through the composting process and contaminate the finished compost product. The result is the entire bin load is either rejected at the gate or diverted to landfill, which defeats the purpose of the FOGO program and triggers contamination charges for the business that filled the bin.
For a Melbourne cafe, restaurant, or commercial kitchen, the practical FOGO checklist is short. Use only AS 4736 certified compostable bin liners in any kitchen caddy or food-scrap collection bin. Store the unused liners in their box - they can degrade over time if left exposed to heat and humidity. Replace liners daily in a commercial setting and tie them off rather than over-stuffing, because over-tightened liners take longer to break down at the composting facility.
Which Melbourne Councils Require Certified Compostable Liners?
FOGO collection programs are now active for commercial premises in Yarra, Port Phillip, Merri-bek, Maribyrnong, Stonnington, Boroondara, and Whitehorse, with progressive rollouts continuing across other metropolitan and regional councils. Each council publishes its own contamination rules but the common requirement is consistent: bin liners used inside FOGO bins must be certified to AS 4736 or AS 5810. Plastic shopping bags, "biodegradable" non-certified bags, and standard kitchen tidy liners all trigger contamination flags. The detailed list of accepted bag types is published on each council's commercial waste page - check before you order. shop FOGO compliant 8L kitchen bags Melbourne ->
