North Harbour Drug Testing

Gary Howarth – General Manager

I joined the TDDA team in December 2015 taking over the new North Harbour franchise in Auckland, after 26 years employment as an investigator, and security and risk consultant. 10 of those years were with the New Zealand Police, where I was a Detective Sergeant.

Most recently I have been working throughout New Zealand and overseas consulting to numerous international, and small to medium sized businesses, as an investigator, and security and risk consultant. I am ISPS (International Ship and Port Facility Security) qualified for Maritime security, including specialising in anti-piracy suppression, and spending time based in Yemen and undertaking patrols of the Gulf of Aden. I have also been involved with the NZ Institute of Professional Investigators at Board level and in 2011 I was a Team Leader for the EQC based in Christchurch.

The majority of my recent work has involved reviewing security at work sites, and implementing policy and management systems, in consultation with Health and Safety managers. I am a certified auditor for Occupational Health and Safety as well as Security Management Systems and Port Facilities.

I am well qualified to advise on Health and Safety within the workplace, and can assist in education, advice, training and policy provisions under the obligations of Health and Safety legislation in relation to drug and alcohol policy.

I am a past President of North Harbour Rugby and currently a Director on the Board, as well as a Director on the Windsor Park Board. North Shore ‘born and bred’ I’m passionate about the region and live locally with my wife Tracey and our 17-year-old son and 14-year-old daughter.

TDDA North Harbour’s main clinic is located in the hub of the North Shore in Constellation Drive, with a clinic also in Henderson and another one recently opened in Warkworth.  The team offers a range of services – drug & alcohol testing at these clinics, pre-employment testing, onsite mobile van testing, 24-hour call out, policy writing, training & education.

Being North Harbour born & bred I’m passionate about the area I work in and have enjoyed watching North Harbour and the greater area expand over the years, and in tandem with the growth, there’s been a huge rise in the of need for professional drug & alcohol workplace testing and related services.

The TDDA North Harbour team is dedicated, hardworking and professional, and strives to help make North Harbour workplaces a safer place for everyone.

Contact Us

North Harbour Clinic

44m Constellation Drive
Mairangi Bay


09 909 6657

Postal Address

PO Box 101 612
North Shore
Auckland 0745

Gary Howarth

Gary Howarth

General Manager

Mobile: 021 807 668
DDI: +64 9 909 6657

Josh Howarth

Josh Howarth

Operations Manager

Mobile: 021 205 6411
DDI: +64 9 909 6657

TDDA North Harbour are proud sponsors of:

  • North Harbour Rugby Union
  • North Harbour Hockey Association
  • Becroft Park Tennis Club
  • New Zealand Breakers Basketball

TDDA North Harbour are members of:

  • North Harbour Club
  • Business North Harbour

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Pre-Employment Testing

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