Which areas in the property are contaminated?
A Baseline Infield Composite test or a Standard Screening Assessment is the first step to establish if a property is contaminated.
Following a positive result, the next step, depending on the level of meth detected in the initial screening tests is discrete area by area individual samples i.e.: Insights or a detailed Contaminated Site Inspection.
The discrete area by area sampling method establishes which areas are contaminated; identifies levels in those areas to facilitate cleaning and/or confirms the property is habitable for a tenant.
Individual kits are used to sample individual areas and each sample is analysed at the lab separately so this method of sampling complies with Standard NZS8510 and NIOSH9111.
The Standard NZS8510 was released in June 2017 and recommends acceptable post decontamination levels of methamphetamine residue in property including, but not limited to dwellings, sheds, garages, vehicles, boats, caravans, mobile homes, work places, hotels, motels and storage facilities
If the level of methamphetamine residue detected by the lab in the discrete individual samples is at or less than 1.5 micrograms/100cm² per sample, the property can be tenanted.
If the level of methamphetamine residue in any discrete individual sample exceeds 1.5 micrograms/100cm² professional decontamination is likely to be required in those areas.
And it should be anticipated that a rental property may be considered inhabitable under the Residential Tenancies Act 1986 if the level of methamphetamine residue in any one individual area exceeds the levels referenced in NZS8510.
As with other methods of sampling, the recommended approach for discrete area by area individual samples is to sample all areas in a property. The less areas that are sampled, the greater the risk problematic levels of methamphetamine residue may be missed.
When to use Insights discrete area by area sampling
Where initial screening tests have identified methamphetamine residues less than 3 micrograms and; there are no complicating factors such redecoration or renovation which could mask meth residues.
If the results of initial screening tests exceed 3 micrograms a Contaminated Site Inspection is recommended which includes discrete area by area individual samples with a detailed Remediation Action Plan to support an insurance claim and third party professional decontamination and a walk through video.
Please note Insights discrete area by area individual sampling does not include a Remediation Action Plan.
Our investigation unit Contaminated Property Investigations New Zealand [CPINZ] specialise in Contaminated Site Inspections.
Our CPINZ technicians can also undertake sub-surface individual samples where initial screening tests identified methamphetamine in a recently redecorated property.