Reasonable Suspicion in a Safety-First Workplace: What Every Safety Manager Needs to Know

Employee drinking alcohol at work

I've spent more than 20 years in the background screening and drug testing industry. In that time, I've sat across from hundreds of safety managers, and I can tell you the conversation that makes them most uncomfortable isn't about injury rates or OSHA audits.

It's this one: "I think one of my employees came in impaired today. What do I do?"

Reasonable suspicion is one of those topics that lives in the gap between policy and reality. Most organizations have a drug and alcohol policy. Far fewer have safety managers who feel genuinely equipped to act on it when the moment arrives. That gap is exactly where workplace incidents happen.

As someone who will be presenting on this topic at the ASSP Safety '26 Conference this June, I want to start laying out the foundation now because this conversation is too important to wait for a conference session.

Why Safety Managers Are in a Harder Position Than HR

Reasonable suspicion training is often framed as an HR function. And while HR absolutely needs to be involved, safety managers carry a different kind of weight in this moment.

You're typically closer to the floor. You see the employee before HR does. You're the one who has to make a real-time call about whether someone is fit for duty and in a safety-sensitive environment, that call has immediate consequences. A wrong decision in either direction doesn't just create a compliance problem. It creates a safety problem.

That's a fundamentally different pressure than an HR manager reviewing documentation after the fact.

What Reasonable Suspicion Actually Means

Let me be direct about something: reasonable suspicion is not a gut feeling, and it is not a zero-tolerance reflex. It is a structured, observable, documentable process.

To initiate a reasonable suspicion test, a trained supervisor or manager must be able to articulate specific, contemporaneous observations about an employee's appearance, behavior, speech, or body odor that are consistent with the use of alcohol or a controlled substance. "Something seemed off" is not enough. "The employee's speech was slurred, their eyes were glassy, and they were unable to complete a pre-shift equipment check they perform daily"; that is enough.

The standard exists for two reasons. First, it protects employees from arbitrary or discriminatory action. Second, it protects you and your organization when the process is challenged, and it will be challenged.

The Cannabis Complication

Here's where reasonable suspicion gets significantly harder in 2026 than it was five years ago. Cannabis is now legal for recreational use in 24 states and for medical use in the majority of the country. More employees are using it. And unlike alcohol, cannabis does not have a reliable impairment marker tied to a specific measurable threshold. A positive drug test tells you someone used cannabis. It does not tell you they are impaired right now, at work, on your floor.

This creates a genuine challenge for safety managers. Your policy may still prohibit cannabis use and in safety-sensitive roles, it absolutely should — but your reasonable suspicion process has to be grounded in observed impairment, not assumption based on known legal use outside of work.

What does cannabis impairment actually look like? Some indicators overlap with alcohol: slowed reaction time, impaired coordination, altered perception, bloodshot eyes, difficulty tracking conversation. Others are more specific. The key is that your supervisors need to be trained on what to look for and how to document it before the moment arrives, not during it.

The Four Pillars of a Strong Reasonable Suspicion Program

Whether you're building a program from scratch or strengthening an existing one, a solid reasonable suspicion process rests on four pillars:

1. Training — for supervisors, not just HR. Your safety managers and frontline supervisors need dedicated, documented training on how to recognize signs of impairment, how to approach an employee, and how to initiate the testing process. This training should be repeated, not a one-time onboarding checkbox.

2. Documentation — real-time, factual, specific. When a supervisor observes concerning behavior, they need to write it down immediately, in objective language, before the conversation with the employee happens. Vague documentation is almost useless if a decision is later challenged.

3. A defined process — so no one is improvising under pressure. Who does the supervisor call first? Who accompanies the employee to testing? What happens if the employee refuses? Every step should be mapped out and accessible before anyone needs it.

4. Consistency — applied regardless of tenure, role, or relationship. One of the fastest ways to invalidate a reasonable suspicion process, legally and culturally, is to apply it selectively. Consistent application is not just a legal protection. It's a fairness principle that safety-oriented organizations should take seriously.

The Cost of Getting This Wrong

I want to be honest about what happens when this process breaks down, because I've seen it from both directions.

When safety managers act without documentation and without a defined process, they expose their organizations to wrongful termination claims, discrimination allegations, and OSHA complications. The intent to protect the workplace doesn't shield you from a flawed process.

When safety managers hesitate, when the discomfort of the conversation leads them to overlook observable signs of impairment, people get hurt. Equipment gets damaged. Incidents happen that a functional reasonable suspicion process would have prevented.

Neither outcome is acceptable. And both are avoidable with the right preparation.

What's Coming Next

This post is the first in a series I'll be building out leading into my session at ASSP Safety '26 in June. In the coming weeks, I'll be going deeper on cannabis-specific impairment indicators, the documentation framework that holds up under scrutiny, and how to structure supervisor training that actually changes behavior rather than just checking a box.

If your organization is navigating any of this right now, whether that's updating your policy, training your supervisors, or figuring out how to handle a situation that's already arisen, reach out. This is exactly what we do.

Michael Barnes | michael@uniquebackground.com | uniquebackground.com