Workplace drug detections for methamphetamine are surging, and it’s a trend that’s putting the construction industry on alert.
According to recent data from The Drug Detection Agency (TDDA), positive workplace tests for meth have climbed sharply this year, from 13.7% in January to 24.9% in March. The highest detection rates were found in regions not typically considered hotspots, including Central North (30.6%), Taranaki (27.9%) and Taupō/Rotorua (25%).
“Meth isn’t just a big-city problem anymore,” says Glenn Dobson, CEO, TDDA. “We’re seeing a troubling spike in smaller regions and across sectors where safety is non-negotiable. The reality is that your crews are often working around heavy machinery, power tools, or on high scaffolds. One bad decision or impaired judgment can have devastating consequences.”
For builders and contractors, this sharp uptick has serious implications. It raises not only health and safety concerns, but also legal and operational risks if policies aren’t watertight and consistently applied.
A wake-up call for employers
Dobson says these figures should serve as a wake-up call for employers all workplaces, but particularly in building and construction, especially those operating in remote or regional areas where support services may be harder to access and meth use is on the rise.
“This is about protecting people, productivity, and your business. Employers must have clear drug and alcohol policies in place, and more importantly, follow them.”
Failure to stick to policy is where many businesses fall short, leading to legal vulnerabilities and inconsistent disciplinary processes. TDDA advises that drug policies must outline the types of testing used, from pre-employment to random, reasonable cause, and post-incident, and define what constitutes a breach.
“A policy isn’t just paperwork,” Dobson says. “It needs to be part of how your business operates every day.”
Knowing the signs
Construction site managers and supervisors play a critical role in spotting warning signs of meth use: erratic behaviour, paranoia, extreme talkativeness, sweating, crashing or even sleeping on the job. But confrontation is not the answer.
“You need a discreet, compliant approach,” says Dobson. “Remove the person from safety-sensitive tasks, refer to your policy, and initiate reasonable cause testing, all without putting others at risk. Our tools and training help managers do this calmly, compliantly, and without escalation.”
Training leaders to act safely and compliantly is essential. TDDA’s tools, including policy compliance apps, can support real-time decision-making while reducing legal exposure.
Four-layered testing regime
TDDA recommends a four-layered testing regime for high-risk industries like construction:
- Pre-employment testing – Sets clear expectations from day one.
- Random testing – Acts as a deterrent and reinforces a safety culture.
- Reasonable cause testing – Provides a reactive safeguard when behaviour raises flags.
- Post-incident testing – Helps determine if substances contributed to an accident.
TDDA’s new nine-panel testing devices now also screen for emerging opioid threats like fentanyl and tramadol, with no added cost.
Monthly random testing of a proportion of the workforce is considered best practice for construction businesses, particularly those involved in infrastructure, civil works, or commercial builds. though testing frequency and scope should be tailored to each organisation’s risk profile.
In the face of rising meth detections, the best defence is a well-trained team, a strong policy, and a proactive testing programme.
“Testing isn’t about catching people out, it’s about setting a standard,” Dobson says. “When you’ve got your crew’s backs and they know you’ve got systems in place to protect them, it lifts the standard for everyone. That’s how we keep sites safe and jobs on track.”