The different methods of sampling using a laboratory.

In New Zealand there are several types of testing methods depending on the client's requirements. These are also referred to by different names throughout the industry which can make the whole thing very confusing. Below is a list of different methods and a breakdown of each one.

Actual Name: Field Composite
Industry Names: Level One, Stage One, Base Test, On Site Test, Screen Test
Not to be confused with: Indicative test kits (kits that show an indication on site)

Breakdown: In a Field Composite test, the sampler takes multiple samples from throughout the property and inserts the swabs into a single test tube. The purpose of the test is to advise the client whether there is any trace of methamphetamine present and if there is a need for further investigation.

Pros: As the sampling company is only being charged for sending minimal test tubes to the laboratory the cost to the client is relatively low.

Cons: Because all samples are inserted into the same sample test tube there is no way of knowing which area holds contamination so there is a need to re-visit the property to gather individual samples if the original test shows contamination.

Actual Name: Laboratory Composite
Industry Names: Laboratory Composite

Breakdown: This type of testing is similar to In Depth testing where a sampler takes individual samples in adherence with NIOSH 9111. The individual samples are sent to the laboratory but instead of being analysed individually they are run in batches of up to five samples per batch. The laboratory then reports the analysis of each batch and an average result.

Pros: Because the samples are already individually at the laboratory, should the batch show contamination the laboratory can quickly re-run the samples individually to give you a break down of contamination on each sample without the need for a sampler to re-visit the property.

Cons: The initial cost of the laboratory composite is more expensive than a Base Test so this type of test if normally designed for clients who already have a suspicion there is contamination within the property.

Actual Name: NIOSH: 9111
Industry Names: Comprehensive test, Level Two, Stage Two, In Depth Test, Detailed Test
Not to be confused with: This type of testing is often confused with full reports and other types of sampling such as soil sampling, lead, pH and decontamination notes (this type of reporting is normally done by Laboratories or Occupational hygienists and normally cost in excess of $2000)

Breakdown: NISOH 9111 (link here) is the method in which samples are required to be taken to adhere with best practice. It sets out the way a sample is to be taken, the material of the surface sample, the type of substance the gauze is to be soaked in and the size of the sampling area. 

Pros: Individual analysis of each sample means you know which areas are effected.

Cons: As each sample is analysed there is a laboratory cost for each sample so it is the most expensive type of test. 

If you need assistance with further understanding the type of tests or if you have a report from Meth Testing NZ or another company please don't hesitate to contact us: 0800 34 34 33 or