A Baseline Screening Assessment, or BSA, is the standard screening method for identifying whether methamphetamine residue is present at a property.

It is designed to provide a practical, documented baseline result. This can help buyers, sellers, landlords, and property managers make informed decisions before purchase, between tenancies, or where there are signs of possible meth-related risk.

A Baseline Screening Assessment identifies whether meth residue is present and whether further investigation may be required.

We use field composite surface sampling. Five representative surface samples are collected and combined into a single field composite sample, which is sent to an independent accredited laboratory for analysis.

Yes. A pre-purchase meth test helps identify potential contamination before you go unconditional.

Meth residue is often invisible and may not be disclosed unless it has already been identified. Testing gives buyers clearer information before committing to a purchase, especially where the property has been rented, recently renovated, poorly maintained, or has an unknown occupancy history.

Because property purchases are not the same as rental compliance decisions, buyers may choose to rely on NZS 8510:2017 or other risk-based advice when deciding what level of meth residue is acceptable to them.

Any property can be tested before purchase, but testing is especially important where the property:

• has been used as a rental
• has had multiple occupants
• has signs of poor maintenance or unexplained damage
• has recent repainting or repairs
• has an unknown history
• is being purchased as an investment property

Rental properties often present higher risk because there may have been multiple occupants over time and limited visibility over past activity.

Yes, in many cases a Baseline Screening Assessment, or BSA, can satisfy a methamphetamine or toxicology condition in a Sale and Purchase Agreement, provided the clause does not specifically require a Detailed Assessment, individual laboratory testing, or another defined testing method.

A BSA provides a documented screening result that helps the purchaser decide whether to proceed, request further testing, renegotiate, or withdraw under the terms of their agreement.

If meth is not detected, or results are below the relevant decision-making threshold, the purchaser may have enough information to satisfy the condition. If meth is detected at elevated levels, further testing such as Area-by-Area testing or a Detailed Assessment may be recommended before the condition is confirmed as satisfied.

Because Sale and Purchase Agreement wording can vary, purchasers should always check the specific toxicology clause and seek advice from their lawyer or conveyancer if they are unsure.

Disclosure obligations and buyer risk are not always the same thing.

The 2026 rental regulations apply to residential tenancy situations. They do not remove the relevance of NZS 8510:2017 for sale and purchase decisions, nor do they prevent buyers, insurers, lenders, or future purchasers from taking a more cautious view.

A property may have meth residue below the rental contamination threshold but still be relevant to a buyer’s decision, future resale, insurance position, lending confidence, or personal risk tolerance.

Testing gives buyers independent information before they commit, rather than relying only on what is already known or required to be disclosed.

Usually, no.

A screening assessment can normally be completed quickly, with results often available in as little as 24–48 hours. This usually fits within standard conditional contract timeframes, especially where testing is arranged early.

Yes, depending on the result.

If contamination is detected, a buyer may request further testing, renegotiate the purchase price, ask for remediation, or reconsider the purchase. If results are clear, the report may support buyer confidence and reduce uncertainty.

Testing helps both buyers and sellers make informed decisions based on evidence rather than assumptions.

Buyers can request meth testing as a condition of the Sale and Purchase Agreement, often through a toxicology or methamphetamine testing clause. If the property is tenanted, the real estate agent must seek permission from the tenants for testing to be undertaken. Tenants have the right to refuse.

If testing is refused, or if the clause is removed, the buyer should consider whether they are comfortable proceeding without independent evidence. In that situation, legal advice is recommended before going unconditional.

In some cases, yes.

Pre-sale testing can help sellers identify potential issues before they become part of a negotiation or disclosure dispute. A clear report may also help provide confidence to buyers, especially where the property has previously been rented or where the seller wants to reduce uncertainty before listing.

No. Because the five samples are combined and analysed as one field composite sample, the laboratory result cannot determine the individual result or concentration at each sampled location.

Red LBP’s toxicology service is a screening assessment and is not designed for insurance, tenancy compliance, evidential or contamination-clearance purposes. If testing is required for one of these purposes, you should confirm the testing requirements with the relevant insurer, authority or an appropriately qualified specialist testing provider before proceeding.