On 22 May 2026, Standards Australia published AS 5407.3, the world's first national consumer-product standard for testing carbon dioxide rebreathing risk in infant sleep products. No other country has one. This isn’t a routine standards update or a quiet revision. It’s a genuine turning point in how the safety of infant sleep products can be measured.
If you've heard the news and you're wondering what it means for the products in your nursery, you're in the right place.
The short version: you haven't done anything wrong, there's no reason to panic, and what's just happened is good news for parents because a word the industry has leaned on for years is finally being retired to make way for claims that can be tested against real science.
What follows is the longer version: what AS 5407.3 actually is, why using "breathable" is no longer acceptable, and the single question worth asking any brand from here on.
What is carbon dioxide (CO₂) rebreathing?
AS 5407.3 is a voluntary standard that introduces consistent testing and design parameters for measuring CO₂ rebreathing risk in infant sleep products and will have a significant impact on any products marketed as “breathable” [1].
This standard gives a consistent, scientific way to measure how much carbon dioxide can build up in the sleep surface when an infant breathes against it. CO₂ rebreathing is a recognised contributing factor in sleep-related infant deaths, supported by more than thirty years of peer-reviewed research.
The test uses a mechanical infant-sized doll positioned “face down” to simulate the breathing of a 2- to 6-month-old infant, the age range when the risk of Sudden Unexpected Death in Infancy (SUDI) is highest. It measures the level of carbon dioxide in the “lungs” of the doll over time. If the carbon dioxide level rises and exceeds the agreed safe level specified in the standard, then the product fails.
Most importantly, the standard tests products in the same way they're actually used at home, not just in isolation. For example, a mattress with a sheet over it or a mattress with a protector and a sheet. Real-world testing has revealed that product combinations can behave very differently compared to individual products tested on their own, and the standard has been designed to capture that.
A surface that passes alone might fail if another untested product is used in combination.
The science supporting carbon dioxide rebreathing is not new, extending all the way back to 1998 [2,3].
What’s new is that, for the first time ever, Australia has translated that body of science into a reproducible national standard that can be applied to products.
For the story of how the standard was built, the suite of standards it belongs to, the regulators and health bodies behind it, and what it took to get here, see the article co-authored by Little Human Linens and INPAA on the INPAA website.
For the broader breakdown of how products meet Australia's 2026 mandatory standards, see our 2026 standards explainer.
Why is "breathable" being retired?
"Breathable" describes air permeability — how readily air passes through a fabric. And in some contexts, for instance in moisture management in clothing, it describes a real and useful property.
The word was adapted and used as the go-to word for the infant sleep category to communicate airflow safety. It's on labels, on mattresses, on sheets, on mattress protectors. And while it sounds protective, it simply doesn’t translate to sleep safety, and the intuition the word creates is actually the opposite of what the science tells us is safe for a baby.
Air permeability and rebreathing protection are independent properties; how “breathable” a fabric is does not reliably predict how safe it is to breathe against it.
The protective mechanism in CO₂ rebreathing isn't airflow through the surface. It's a barrier that prevents exhaled CO₂ from being absorbed into the sleep surface in the first place, keeping the air at the surface where the room can carry it away.
You're not looking for a surface that lets air pass through. You're looking for a barrier to keep your baby's exhaled breath out. Not airflow — a barrier.
The Australian Competition and Consumer Commission (ACCC) has acknowledged publicly that "breathable" has no agreed scientific definition in this category[5]. Historically brands reached for the word because it sounded safe and there was nothing more precise to use; parents understood it as protective because the word implies it.
The confusion was never deliberately deceptive. But it was real, and the consequence was that a marketing word was implying a benefit the science didn’t actually back.
At Little Human Linens, we retired "breathable" from our marketing years ago. The peer-reviewed science on CO₂ rebreathing was already settled and pointed in one direction. We commissioned independent testing of our own products and we've held the position publicly and consistently in the years since.
The standard publishing now is what allows the rest of the industry to do the same, with consistency, against a single yardstick.
What changes now?
First, "tested to AS 5407.3" becomes a verifiable claim. A brand or retailer can be asked to produce a test report. A regulator can audit the claim. A consumer protection body can act if it's misused.
Second, the standard becomes available for the ACCC to reference in future mandatory safety requirements. The Consumer Goods (Infant Sleep Products) Safety Standard 2024, already mandatory from 19 January 2026, is the natural vehicle for future regulatory uptake[6]. AS 5407.3 is now in position to be referenced when those regulations are next updated.
Third, major retailers can choose to require AS 5407.3 testing as a condition of stocking products, lifting the safety of the entire category.
While AS 5407.3 publishes as a voluntary standard, voluntary in this category does not mean optional. This standard was driven by the industry and responsible brands, manufacturers and retailers have already adopted it.
What doesn't change?
The current safe sleep guidelines remain the single most powerful protective factor any parent can give their baby. Back to sleep, on a firm flat surface, in a clear cot, face uncovered, in the same room as a parent for the first 6 to 12 months.
AS 5407.3 supports existing safe sleep principles — it does not replace them.
For comprehensive safe sleep guidance refer to Raising Children Network, Australia's leading safe sleep resource.
What should parents ask when purchasing products to check for rebreathing safety?
Does this product help reduce the risk of rebreathing, and has it been tested to the new standard?
Ask it when you are purchasing a bassinet, co-sleeper, mattress, a sheet, or anything your baby is going to sleep in or on.
What you want to hear back is specific:
✅ Yes, this product is independently tested to AS 5407.3
✅ Yes, we’ve been independently tested for rebreathing risk to the new Australian standard
✅ Not yet, but we're in the process of being tested, and here's where we are.
What you don't want to hear is a redirect.
❌ Our fabric is very breathable.
❌ Our products are rigorously tested.
❌ Designed with infant safety in mind.
❌ Our mattresses meet firmness standards.
Each of those answers might be true. None of them is an answer to the question about rebreathing safety. A brand that has tested to AS 5407.3 can produce the document; a brand that hasn't will reach for adjacent language.
The rule is simple: if the answer doesn't name the standard and doesn't point to a test report, the answer is no.
About the author
Kellee Eriksson is the founder of Little Human Linens, an Emergency Nurse with 15+ years of clinical experience, and an INPAA (Infant and Nursery Products Alliance of Australia) Baby Safety Ambassador. She participated in industry consultations during the development of Australia's 2026 infant sleep surface safety standards and is actively involved in the current rollout. She built Little Human Linens because safe sleep products should be easy to find, easy to understand, and easy to trust.
References
- Standards Australia. AS 5407.3 — Methods of testing infant sleep surfaces, Method 3: Test for carbon dioxide and associated requirements. Standards Australia.
- Carleton JN, Donoghue AM, Porter WK. Mechanical model testing of rebreathing potential in infant bedding materials. Archives of Disease in Childhood 1998;78(4):323–328. doi:10.1136/adc.78.4.323.
- Kemp JS, Livne M, White DK, Arfken CL. Soft bedding and rebreathing potential during sleep. Pediatrics. 1998;102(3):e29.
- Barker R, Leshner MD. Investigation of suffocation mechanisms in the infant sleep environment using a mechanical breathing model simulation. Cureus 2025;17(2):e78852. doi:10.7759/cureus.78852.
- Australian Competition and Consumer Commission. Consultation on infant sleep products and breathability claims. Product Safety Australia.
- Consumer Goods (Infant Sleep Products) Safety Standard 2024. Federal Register of Legislation, F2025C00270. Australian Government.
