A meth toxicology report is the laboratory document that presents the results of methamphetamine surface testing. Whether you are a landlord reviewing a pre-tenancy baseline test, a buyer assessing a pre-purchase meth check, or an insurer evaluating a meth contamination insurance claim, knowing how to read the report is essential. This guide explains the key sections and what the numbers mean.
Key Sections of a Meth Toxicology Report
A standard laboratory toxicology report includes the following sections:
- Laboratory details: The name and IANZ accreditation number of the laboratory that performed the analysis. If this is missing or the laboratory is not accredited, the report may not be legally defensible.
- Property and client information: The address of the tested property, the date of sampling, and the client who commissioned the test.
- Sampling summary: A table listing each sample by reference number, the location where it was collected (e.g., "living room — wall"), the surface area sampled, and the result.
- Results table: The core of the report — showing the methamphetamine concentration for each sample in µg/100 cm², along with the limit of reporting (LOR) and whether the result is above or below the 1.5 µg/100 cm² threshold.
- Chain of custody: Documentation showing who collected the samples, when they were collected, and who handled them from the property to the laboratory. This is critical for legal admissibility.
- Conclusions: A summary stating whether the property meets or exceeds the NZS 8510:2017 standard.
Understanding µg/100 cm² Results
Every sample result in the report is expressed in micrograms per 100 square centimetres (µg/100 cm²). This unit tells you how much methamphetamine residue was found on a standardised surface area. The NIOSH 9111 sampling protocol specifies a 100 cm² sampling area, so the result directly represents the concentration on that area.
You will typically see one of three result types:
- "Not detected" or "ND": No methamphetamine residue was found above the laboratory's limit of reporting. This is the best possible result — the surface is clean.
- A value below 1.5 µg/100 cm²: Methamphetamine was detected, but at a level below the NZS 8510:2017 decontamination threshold. For non-rental situations, the property meets the standard. For rental properties, the relevant threshold under the 2026 Residential Tenancies regulations is 15 µg/100 cm².
- A value at or above 1.5 µg/100 cm² (non-rental) or 15 µg/100 cm² (rental): The surface exceeds the applicable threshold. The property must be assessed and may require decontamination and re-testing before reoccupation.
Composite vs Discrete Results in the Report
If your testing used composite sampling, the report will show a single result for the combined sample group. This result represents the combined residue from all surfaces in the group. If the composite result is below the threshold, all surfaces in the group are considered to meet the standard. If the composite result exceeds the threshold, the report should indicate that further discrete testing is required to identify which specific surfaces are contaminated.
If your testing used discrete (individual) sampling, each surface will have its own result. This gives you a clear picture of which rooms and surfaces are contaminated and at what concentration — essential for decontamination planning and legal evidence.
What to Check Before Relying on a Report
Before relying on a meth toxicology report for legal, insurance, or transaction purposes, verify the following:
- The laboratory is IANZ-accredited (or equivalent under a mutual recognition arrangement).
- Samples were collected in accordance with NZS 8510:2017 and the NIOSH 9111 protocol.
- The chain of custody is complete and unbroken from sampling to analysis.
- The report includes the sampling date, property address, and a clear results table with µg/100 cm² values.
- The conclusions clearly state whether the property meets or exceeds the applicable threshold (1.5 µg/100 cm² under NZS 8510:2017 for non-rental, or 15 µg/100 cm² under the 2026 Residential Tenancies regulations for rental properties).
What to Do If Results Exceed the Threshold
If any sample in the report exceeds the applicable threshold — 1.5 µg/100 cm² under NZS 8510:2017 for non-rental situations, or 15 µg/100 cm² under the 2026 Residential Tenancies regulations for rental properties — the property must be assessed and may require decontamination. See our guide on what happens after a positive meth test for the full decontamination and clearance testing process. For a broader understanding of meth testing documentation, see understanding meth reports. To commission a toxicology report for your property, see our toxicology reporting service.