Meth testing sounds like one thing. It is actually three different services with three different price tags, and choosing the wrong one is how people end up paying for a decontamination twice the size it needed to be.
This is the mechanics: what gets sampled, how, what the laboratory does with it, and what you should have in your hand at the end. If you already have a result and want to know what the number means, that is meth testing levels explained.
The high deposition points a sampler works to. Where the swab goes decides what the result means.
The three kinds of meth test, and when each one is right
There are three levels of meth testing in Australia: a presumptive field screen, a composite laboratory screen, and a discrete laboratory assessment. They answer different questions, and only the last two produce a number you can act on.
| Test type | What it answers | What you get | Use it when |
|---|---|---|---|
| Presumptive field kit | Is there anything here at all? | A colour change. Presence or absence, no concentration. | Routine checks between tenancies, or deciding whether to escalate to a laboratory. |
| Composite laboratory screen | Is this property above the 0.5 threshold? | One number, averaged across several pooled surfaces, from an accredited laboratory. | Pre purchase screening, portfolio checks, ruling contamination out. |
| Discrete laboratory assessment | Which rooms are affected, and how badly? | A result per sample point, plus a written site characterisation. | Any property that has already returned a positive. |
The mistake we see most often: a composite screen comes back positive and the owner goes straight to remediation quotes.
A composite says the house is contaminated without saying where. A remediator holding that report has to scope the whole property, because there is nothing in the document letting them exclude anything. Spending another $800 to $1,500 on discrete sampling routinely takes five figures off the remediation.
Presumptive kits: what they do, and where they stop
Kits have a real place. A landlord checking between tenancies, or a buyer wanting a rough indication before committing to a full inspection, is using one correctly. The trouble starts when a kit result gets treated as a finding.
They detect, they do not measure
A kit reacts to a class of compounds and changes colour. It cannot tell you whether a surface reads 0.6 or 16, and 0.5 µg/100cm² is a concentration. There is no way to compare a colour change to a threshold.
False positives are real
Some household cleaning products and chemicals can trigger a reaction. A positive kit result on a freshly cleaned property is worth confirming before anyone panics.
Surfaces only
A kit tells you about the spot you swabbed. It says nothing about residue inside wall cavities, above ceilings or in the air conditioning, which is where a lot of the problem sits.
No chain of custody
Nobody independent handled the sample and nothing was sealed or logged. That makes a kit result close to useless in an insurance claim or at a tribunal.
Send-in kits are a middle option
Some kits include laboratory analysis of the swab you post back. That gives you a real number, though still without an independent sampler or a defensible sampling plan.
A positive kit means escalate
Not remediate. The next step is an accredited laboratory screen, and on a positive screen, discrete sampling. Acting on a colour change is how people end up paying for the wrong scope.
The honest advice: use a kit to decide whether to test properly. Never use one to decide whether to remediate, and never use one to start a disclosure conversation you cannot take back.
What actually happens on the day
Walk through and history
Before anything is swabbed, the assessor walks the property and asks questions. Tenancy history, complaints, odours, staining, what the neighbours said. The sampling plan comes out of that conversation, not out of a template.
The sampling plan gets written down
Which rooms, which surfaces, how many samples, composite or discrete. It should exist on paper before the first swab, because a plan invented as you go cannot be defended later.
Surfaces are templated and swabbed
A 100cm² template is placed on the surface and a solvent moistened wipe is worked across it in a set pattern. The template is not a formality. The result is expressed per 100cm², so if the area is not measured, the number is wrong before it leaves the house.
Samples are sealed and logged
Each wipe goes into a labelled container, sealed, and entered on a chain of custody form with time, location and who handled it. This is the step cheap operators skip, and it is the step that decides whether your result survives a challenge.
The laboratory runs the analysis
Three to five business days is standard. Express turnaround exists at a premium.
The report is written and interpreted
The laboratory reports concentrations. Turning those into a scope of works is the assessor’s job, and it is where the value sits.
On a standard three bedroom house, the on site portion takes an hour or two. The waiting is the long part.
What the laboratory actually does
The wipe arrives at a laboratory and goes through extraction and instrumental analysis. Most Australian laboratories work to variations of the NIOSH 9111 method for methylamphetamine on wipe media, using gas chromatography mass spectrometry or liquid chromatography tandem mass spectrometry.
What that buys you
Chromatography separates the compounds in the sample. Mass spectrometry identifies them by mass. Together they do not just say “something drug like is present”, they identify methylamphetamine specifically and quantify how much.
That specificity is the whole difference between a laboratory result and a field kit. A kit reacts to a class of compounds. An instrument names the molecule.
NATA accreditation
NATA is Australia’s national accreditation authority. Accreditation is method specific, so a laboratory can be accredited for one analysis and not another. The report should name both.
The method on the report
If the report does not state which method was used, you cannot compare it to anything, and neither can an insurer.
Limits of reporting
Every method has a level below which it cannot reliably quantify. A result of “less than 0.02” means below the reporting limit, not zero.
Units
Results come back in micrograms per 100 square centimetres. Anything expressed as “positive” with no unit is a screen, not an analysis.
Testing and remediation are separate jobs. Where the same firm does both, the clearance test should still be arranged independently.
Chain of custody, and why it decides whether your result counts
Chain of custody is the documented trail from the wall to the laboratory bench. Who took the sample, when, from where, how it was sealed, who transported it, when it was received.
It feels like paperwork until the moment someone disputes the result. Then it is the only thing standing between your report and an argument you lose.
A defensible result has
- A named sampler with stated qualifications
- A written sampling plan produced before sampling
- Individually sealed and labelled samples
- A signed custody form with dates and handovers
- A NATA accredited laboratory named on the report
- The analytical method stated
- Results in µg/100cm² against stated sample locations
Warning signs
- A verbal result, or a number in a text message
- No sample location map or schedule
- Samples taken by the same crew quoting the remediation, with no independent clearance
- A laboratory that cannot be named
- “Positive” or “negative” with no concentration
- A quote issued before the laboratory result came back
On that last one. A remediation quote written before the testing report exists is a quote based on a guess. It might be a high guess or a low one. Either way you have no way of checking it, and neither does your insurer.
What a proper testing report contains
Report checklist
- Property address, date of attendance and name of the assessor
- The sampling plan, with a rationale for the surfaces chosen
- A location schedule or floor plan marking every sample point
- Results per sample in µg/100cm², not averaged into a single figure unless the test was composite by design
- The laboratory name, NATA accreditation number and analytical method
- The reporting limit of the method used
- A statement of what was not sampled, and why
- An interpretation: which areas exceed the guideline and what that implies for scope
- Chain of custody documentation attached
If a report is missing the location schedule or the statement of what was not sampled, it is not wrong exactly. It is just incomplete in the two ways that matter most when you try to use it.
Timing and cost
| Stage | Typical time | Indicative cost |
|---|---|---|
| Initial inspection and scoping | 1 to 2 hours on site | From $120 |
| Composite laboratory screen | 3 to 5 business days for results | $400 to $1,200 |
| Discrete site characterisation | 3 to 5 business days, more samples | $1,200 to $3,000 |
| Post remediation clearance | 3 to 5 business days | $800 to $2,500 |
| Presumptive field kit | Minutes | Under $200, and not a substitute for any of the above |
Because most properties get tested twice, once as a baseline and once as clearance, allow roughly two weeks of calendar time even when the physical works are short. Full pricing detail sits in what meth decontamination costs.
Frequently asked questions
How long does meth testing take?
The on site portion of a standard residential test takes one to two hours. Laboratory analysis is three to five business days in Australia, with express turnaround available at a higher fee. A presumptive field kit gives a reading in minutes, but it does not give you a concentration.
Do I legally have to test my property?
There is no blanket legal requirement to test a property in Australia. The obligations that bite are indirect: disclosure duties on sale in some jurisdictions, a landlord’s duty to provide habitable premises, and council powers where contamination is known. Testing is how you evidence your position under any of them.
Can I take the samples myself and send them to a lab?
Some laboratories will accept owner collected samples, and the result will be analytically valid. What it will not have is an independent sampler, a defensible sampling plan or an intact chain of custody, which is most of what makes a report useful in an insurance claim or a tribunal.
What is the difference between a composite and a discrete test?
A composite pools several surfaces into one sample and returns an average, so it tells you whether the property is contaminated but not where. A discrete test samples surfaces individually and maps the contamination room by room. On a positive property, discrete testing is what keeps the remediation scope from covering the whole house.
Should the company doing my clean also do my testing?
They can do the baseline testing. The clearance test at the end should be arranged independently. A clearance signed by the firm that did the cleaning carries very little weight with an insurer, a purchaser’s solicitor or a tribunal, however good the work was.
What if the test comes back clean but I still suspect contamination?
Check what was actually sampled. A clean result only covers the surfaces in the sampling plan, so a partial test on a property with a known history is a partial answer. Re-testing with a wider plan, focused on high deposition surfaces and the air conditioning, is usually the next step.
The short version
Pick the test that matches the question you are actually asking. A field kit tells you whether to escalate. A composite screen tells you whether the property is over the line. Only a discrete assessment tells you which parts of the property are involved, and that is the document every later decision gets made from.
Insist on a written sampling plan, a NATA accredited laboratory, the method named on the report, and an intact chain of custody. Those four things are what separate a number you can use from a number you will end up arguing about.
Need testing done properly? AllAces has been doing decontamination work in Australia for more than 35 years across more than 65,000 jobs as an IICRC Certified Firm, with 24/7 response in Brisbane, Sydney, Melbourne and Ballarat. Call 1800 00 10 10, or get in touch here.
Costs and turnaround times above are indicative and vary with property size, sample count and laboratory. The 0.5 µg/100cm² figure is the national remediation trigger drawn from enHealth guidance. Last updated September 2026.
This page covers how the sample is taken. It is one part of meth contamination in Australian property, which is where to start if you are still working out whether you have a problem at all.
Once the laboratory report lands, reading it is a separate skill: what your meth testing reading actually means.
Book accredited sampling with clearance reporting included: meth testing and remediation. Call 1800 00 10 10.
