Workplace Drug Testing

Canterbury Health Laboratories is an accredited New Zealand laboratory that provides accurate and sensitive results for drug screening and drug test confirmation using state of the art testing equipment. These results are strictly controlled and able to withstand legal challenge.

CHL Workplace Drug Testing / Toxicology Services:

  • Test for a wide range of illicit drugs, routinely:
    • Amphetamine type compounds (including methamphetamines)
    • Barbiturates
    • Benzodiazepines
    • Cannabinoids
    • Cocaine metabolites
    • Opiates
    • Synthetic Cannabinoids (on request)
  • Detect individual drugs rather than drug classes
  • Have a comprehensive library of over 600 drugs to test against if required
  • Testing for new drugs can be developed within a matter of hours
  • Detection of substances up to 2-3 days after use
  • Confirmation testing conducted without requiring an additional sample
  • Ability to request medical diagnostic tests such as liver function or Complete Blood Count
  • Expert staff interpretation of results
  • Expert advice and assistance with the development of your company policies for drug testing
  • Individual contracts negotiated to suit your company

All workplace drug testing conducted by CHL follows a strict AS/NZS 4308:2008 standard. Following this standard ensures the collection and testing procedures are accurate and able to withstand legal challenge if required.

The testing requires the collection of a urine sample, which can be collected at CHL, or on site at your business provided the standards guidelines are followed. We offer a courier service for businesses throughout New Zealand, which remains covered by the chain of custody and legal standards required under AS/NZS 4308:2008.

The Drug Testing Process

CHL can conduct any form of drug testing for your business – from pre employment checks right through to reasonable grounds testing.

  • all employees to be drug tested are to complete medical and drug consent forms
  • photo identification is viewed
  • process is explained to employee
  • the employee is asked to state any medications that they are taking so there is no confusion with illicit drugs
  • client is tested
  • Sample is checked for tampering (additional sample taken if required)
  • Sample split into two containers
  • Tamperproof seal signed and sighted by employee
  • Chain of custody signed and sighted by employee
  • Samples sent to the laboratory
  • Initial testing conducted – negative samples stored for 2 weeks
  • Non negative samples retested using Gas Chromatography Mass Spectrometry
  • Results sent back to the employer
  • Not negative results are kept for 3 months

Drug Testing Sample Collection

There are several options for collection; one is for you to set up a collection site at your premises. To do this you would need to have a staff member attend and complete an NZQA accredited course in order to be covered legally under the AS/NZS 4308:2008. Alternatively you can arrange for staff to visit our collection centre on Hagley Ave. CHL staff are fully qualified to collect samples for workplace drug testing and are covered under the legal requirements. If you are not located in Christchurch, and do not wish to complete the collection standards we can direct you to your closest collection venue.

The employee’s urine is collected in a specially designed cup with a temperature indictor to ensure the urine has only just been passed. A private secure room is used for the collection. The sample is tested front of the employee to ensure it hasn’t been tampered with. If the sample isn’t satisfactory a second sample is requested. The sample is then split in front of the employee, tamper proof seals signed and sighted by the employee, and all legal paperwork and chain of custody forms signed and sent to the laboratory.

CHL’s Drug Testing Procedure

Initial screening is performed using immunoassay techniques. These assays have a high sensitivity in detecting concentrations of drugs and their metabolites in urine.

The result is determined as either a negative or a not negative result. No further testing action is taken with negative results but the sample is still kept for two weeks in case it is needed. Results deemed not negative are re tested using Gas Chromatography Mass Spectrometry (GCMS). All test results are authorised by our chief scientists who are signatories to AS/NZ 4308: 2008. All test results are sent to the person who requested the testing.


All testing conducted by CHL are in accordance with AS/NZ4308: 2008. This includes our collection kits, chain of custody forms, couriering of samples, and security of samples within the laboratory. The actual Workplace Drug Testing/Toxicology Laboratory where testing occurs is restricted, which means only staff involved in testing are able to enter the lab. The sample fridge is also locked to ensure absolute security for the samples. Specimen packaging and documentation is designed to ensure the integrity of all samples during transport to CHL.

A drug test is a technical analysis of a biological specimen, commonly urine, to determine the presence or absence of specified drugs or their metabolites. Increasingly drug testing is being used by employers to ensure the safety of their staff and businesses, especially in industries seen as safety sensitive, where the use of drugs or alcohol may impair the ability to perform duties safely.