Workplace Cognitive Impairment Testing: Fatigue, Cannabis/Marijuana, and More

This article will provide an overview of the state of impairment testing today and will answer the following questions: 

1. What is impairment testing? 

2. What’s the history of impairment testing? 

a. Increasing  Awareness of Workplace Fatigue

b. Early Obstacles

c. The Role of COVID-19 and Increasing Mental Health Awareness

d. The Legalization of Cannabis

3. What’s the science behind impairment testing? 

a. Cognitive Processes Essential to Workplace Safety and Performance

b. Fatigue vs. Alcohol Intoxication

c. What Impairment Tests Measure

d. Baselines

4. What types of workplace impairment tests are available today? 

5. What are the benefits of impairment tests? 

6. How does impairment testing compare to drug testing? 

7. Is impairment testing right for your company? 


In recent years, and particularly over this past year, workplace impairment testing has achieved unprecedented popularity amongst safety-sensitive workplaces. 

With the increased health and safety threat posed by COVID-19; the legalization of cannabis; the inadequacy of drug testing; and growing workplace mental health issues, safety leaders have been forced to accept change and innovation as the only reasonable path forward. This has placed the spotlight on impairment tests which, as fairly new technologies, have been next in line amongst top safety initiatives patiently awaiting universal adoption. 

If you want to stay ahead of this trend and help your company adapt and remain competitive in the safety arena, you should start learning more about impairment testing now and increase awareness about it within your workplace. 


What is impairment testing? 

According to the National Workrights Institute,

“Impairment testing is the practice of determining which workers in safety-sensitive positions put themselves and others at risk by directly measuring workers’ current fitness for duty.” 

The keyword there is current

As discussed in our Leading and Lagging Indicators article, if your safety procedures don’t anticipate safety risk or identify it in real-time, they’re not all that effective. By focusing on the right indicators at the right times, your team will possess the data and insights that make incidents and accidents suddenly a lot more predictable than before this technology came along. 

Quick recap:

  • Lagging indicators: also known as trailing indicators, are measured by incident numbers, workers’ compensation claims, and past regulatory compliance. Measuring lagging indicators alone provides no real evidence of a safety system’s efficacy because it can create the false impression that an absence of incidents necessarily indicates good safety performance.
  • Leading indicators: are anticipatory rather than “after-the-fact.” They help answer the questions “How are we doing right now?” and “How are we likely to do in the future?”

Thanks to a slew of new technologies sweeping all workplaces, from offices and warehouses to the depths of mines, cognitive impairment tests have become a lot more accessible, flexible, and affordable. This has generated a greater safety focus on leading indicators; more insightful data; more thorough incident analysis, and generally more proactive safety cultures. 

What’s the history of impairment testing? 

Impairment testing as a workplace safety measure is not a new concept. It has roots in the late 1980s and early 1990s, soon after the mandate for drug testing was introduced for federal employees.


Increasing Awareness of Workplace Fatigue

A rise in workplace impairment testing occurred simultaneously with a growing understanding of fatigue’s role in workplace safety lapses and lost productivity, and specifically the negative effects of shiftwork on quality and quantity of sleep.

Consequently, researchers and entrepreneurs began seeking more effective methods to combat worker fatigue in the workplace. This resulted in a number of computer-based cognitive tests designed to measure impaired performance and cognition. Since fatigue’s effect on cognitive processes is similar to that of drugs and alcohol, impairment tests became a top-screen indicator for all forms of cognitive impairment–fatigue due to sleep loss, illness, medication use, dehydration, emotional distress, as well as drugs and alcohol. 

Despite these developments in impairment testing, fatigue management via impairment testing remained a scarce component of workplace safety systems. Beyond personal observation, workplace drug screens endured as the most common method of identifying a potentially impaired employee. 


Early Obstacles

The lack of response to this helpful new technology occurred primarily because early impairment testing proved to be incompatible with the workplace environment. The incompatibility was multifaceted, depending on the type of test and the workplace:

  • First, each impairment test available required proprietary hardware which was not portable or mobile like today’s smartphones and tablets.
  • Second, and unsurprisingly, impairment testing was expensive. 
  • Third, since the tests required expensive proprietary hardware, there were a limited number of testing units which meant it took too long for all workers to complete their tests.

Today, due to COVID-19 concerns and the legalization of cannabis, demand for impairment testing has reached an all-time high (no pun intended). 


The Role of COVID-19 and Increasing Mental Health Awareness

impairment word cloudMental and emotional distress and preoccupation can culminate in a debilitating form of mental fatigue which can be detected via impairment testing. (69% of Your Employees Are Drunk). 

COVID-19 has not only become a constant risk to the physical health of employees–a risk which can be identified via its contribution to fatigue and cognitive impairment–but also to the mental health of employees. According to the CDC, during late June 2020, 40% of US adults reported struggling with mental health or substance abuse. Even before COVID-19 came on the scene, mental health was recognized as a significant problem in the workplace (statistics from, 2019):  

  • 51% of US workers are mentally “checked out” at work.
  • 34% of workers don’t feel safe reporting stress because they think it would be interpreted as a lack of interest or unwillingness to do the activity.
  • Workers say that stress and anxiety affect their work #productivity and coworker relations more than any other factor.
  • Only 43% of US employees think their employers care about their work-life balance.


The Legalization of Cannabis
Meanwhile, as cannabis continues to become legalized in more states and countries, its use is become more widely accepted by society and culture. This leaves safety-sensitive workplaces wondering how and to what degree they can manage cannabis use in their companies. Many companies are finding that their pre-employment drug-tests dissuade too many qualified candidates from even pursuing employment once they are made aware of the company’s drug-testing requirements. This leaves a large population of workers who may indulge in casual cannabis use on weekends and thus do not or cannot pursue employment despite not being impaired when actually clocking into work.
What’s the science behind impairment testing? 

7 cognitive processes


Cognitive Processes Essential to Workplace Safety and Performance

Impairment tests typically measure the functionality of a combination of several cognitive information processes that are essential to the ability of workers to perform their tasks safely, efficiently, and without error (Zhang, 2019):

  • Perception: Recognition and interpretation of sensory stimuli (sight, smell, touch, hearing, etc.).
  • Memory: Short-term/working memory (limited storage), and Long-term memory (unlimited storage). 
  • Attention: Ability to sustain concentration on a particular object, action, or thought, and ability to manage competing demands in our environment.
  • Processing speed: Ability to quickly process incoming visual stimuli, to understand spatial relationship between objects, and to visualize images and scenarios.
  • Executive Functions: Abilities that enable goal-oriented behavior, such as the ability to
    plan, and execute a goal. These include:
  • Flexibility: The capacity for quickly switching to the appropriate mental mode.
  • Theory of mind: Insight into other people’s inner world, their plans, their likes and dislikes.
  • Anticipation: Prediction based on pattern recognition.
  • Problem-solving: Defining the problem in the right way to then generate solutions and pick the right one.
  • Decision making: The ability to make decisions based on problem-solving, on incomplete information and on emotions (ours and others’).
  • Emotional self-regulation: The ability to identify and manage one’s own emotions for good performance.
  • Sequencing: The ability to break down complex actions into manageable units and prioritize them in the right order.
  • Inhibition: The ability to withstand distraction and internal urges.


Fatigue vs. Alcohol Intoxication

The cognitive effects of impairment due to drug or alcohol intoxication are well-researched and widely recognized. Difficulty walking, blurred vision, slurred speech, slowed reaction times, impaired memory, impaired judgment and decision-making, are a few of the most common symptoms. 

Less widely recognized is the fact that impairment due to fatigue often manifests in the same way. Since humans are naturally more vulnerable to fatigue through sleep loss, emotional distress, illness, dehydration, medication use, etc., the levels of impairment and consequent workplace safety risk attributable to fatigue often exceed that of intoxication.

One study compared the cognitive effects of alcohol impairment to fatigue impairment by measuring participants’ performance on a variety of cognitive impairment tests. 

They found that after 24 hours of sustained wakefulness, participants experienced a performance decrement equivalent to impairment due to a BAC of 0.05. (It takes at least four drinks for an average 170-pound male to exceed 0.05 BAC in 2 hours on an empty stomach and three drinks for a 137-pound female (Fell, Voas).) 

The study also found that performance decrements varied depending on the complexity of the cognitive task. For example, after only 13 hours of sustained wakefulness, the level of impairment on reasoning speed matched that of a person with a BAC of 0.05.

Although comparable to the dangerous effects of intoxication, impairment by fatigue is often more subtle and difficult to identify. 


What Impairment Tests Measure

Thus, impairment tests combine a variety of simple and complex tasks to serve as a finer measurement of impairment due to both intoxication and fatigue.

The AlertMeter®, for example, combines perception, decision-making, accuracy, speed, shape recognition, hand-eye coordination, and memory all in one 60-second test. 

The test involves scanning a phone or tablet screen to recognize any differences amongst a variety of presented shapes. The user must determine if all the shapes are the same, or if one of the shapes is different. This measures potential impairment of the perception, pattern recognition, and decision-making processes of the brain. Once reaching a decision, the user must tap the shape that is different or tap a button indicating that all the shapes are the same. 

This challenges the information processing speed, accuracy, response time, and hand-eye coordination processes of the brain. 

Finally, on several screens, they are asked to remember a shape and recall it several screens later. This challenges the short-term memory function of the brain as well as measuring users’ ability to multi-task or switch quickly between tasks.  The inclusion of a memory component in the test is especially effective at identifying cannabis-induced highs in real-time, a feat no other form of drug or impairment testing has accomplished. 

The science is clear that a person impaired by intoxication or fatigue will experience significant challenges in carrying out these processes. Thus, inability to perform on the AlertMeter® impairment test is a strong indicator of user impairment due to intoxication by any substance and fatigue due to any cause. 


Since human cognitive function also includes learning, “individual rolling baselines” are a central component of all successful impairment tests:

“The [impairment] test’s scoring should adjust for the learning that occurs as employees perform the test repeatedly… Typically, this potential problem is handled by establishing a baseline performance level…This baseline is adjusted regularly to compensate for continued improvement due to practice or learning. To assess performance on any given day, the employee’s score is compared with his or her adjusted baseline score” (Butler, Tranter).

Baselines also help personalize user performance and scoring in a way that controls for external variables such as intelligence, language, education level, or familiarity with technology. Essentially, this means that it doesn’t matter how well or poorly a user performs on the test. Instead, what is being measured is the user’s deviation from his/her typical cognitive behavior. Typically, there is slight deviation in everyone’s cognitive performance from day-to-day and even from morning to afternoon. Significant deviation, however, has shown to be an accurate indicator of significant cognitive impairment.

For example, the AlertMeter’s® scoring algorithm and its “rolling baseline” adjusts over time as users’ familiarity and performance with the test improves. If a worker is impaired, their score will fall significantly outside their baseline as shown in the AlertMeter® results graph below. 

Note: AlertMeter® was validated by a NIOSH-funded 2009 scientific study, and further proven through other research studies in addition to 75+ million man hours.


What types of workplace impairment tests are available today? 

Today, workplace impairment tests take various forms: 

  • apps
  • eye tracking devices
  • and wearable technologies.

As discussed in the previous section and as stated by the National Workrights Institute, few early impairment tests were successfully adapted to the workplace. Cost, accessibility, and productivity loss were consistent challenges.

For example, the original Psychomotor Vigilance Test, a precursor to some modern impairment tests, lasts 10 minutes. Modern adaptations like the AlertMeter®have successfully reduced this time to a record 60 seconds without compromising accuracy and insights (Bassner, Rubinstein).

“With the rise and subsequent ubiquity of mobile technology in the mid-2000s, including wi-fi and broadband Internet, touchscreens, tablet computers, and smartphones, workplace alertness testing began to be re-examined. Having developed a computer-based test for measuring cognitive decline in patients with Alzheimer’s dementia, Bowles-Langley Technology adapted the test for potential use in workplace environments. The prototype test was the subject of a NIOSH-funded study in 2009 that confirmed its ability to detect cognitive impairment among sleep-deprived subjects. Because the test was short, lasting two minutes or less, and could run on common, non-proprietary computer platforms, it immediately demonstrated more promise for real workplaces than previous fit-for-duty tests” (Understanding AlertMeter®).

Further, due to the scientific backgrounds of the masterminds (NASA and US Military) who created the first impairment tests, factors such as productivity loss, ease-of-use, worker privacy, and company liability were not adequately considered nor addressed. The few impairment tests that have been successfully integrated into modern workplaces have had to overcome these challenges. Several characteristics of modern impairment tests make them much better adapted to the workplace:

  • Reducing the NASA PVT down to 60 seconds was a feat supported by NIOSH engagement and funding. It ended up being the greatest factor in the success of apps like the AlertMeter®. 
  • Ease-of-use also became a main consideration in the tests which now utilize a
  • Simple, game-like format that can be taken by any person
  • Regardless of language, education level, or familiarity with technology.

With careful consideration of how an impairment test can fit into existing company policies and procedures, concerns such as worker privacy and company liability have also been successfully addressed.

From an interview with a steel company using impairment testing:

Q. What about increased liability? Do you have any concerns about that?

A. Our Labor, HR, and Insurance attorneys told us the AlertMeter® actually de-escalates our liability with another layer of ensuring our folks are fit for duty.(Why Triple-S Steel Uses AlertMeter®)

Despite these recent major developments, the market today remains slim. 

The National Workrights Institute lists 3 companies who still offer impairment testing solutions:

1. Predictive Safety, SRP sells AlertMeter®, a 60-second alertness test accessible on smartphone, tablet, or computers.

sean on alertmeter4 crop-1

2. Eye Dynamics– Eye dynamics manufactures Safetyscope, an ocular system that indicates whether a person is impaired by monitoring their eyes’ ability to smoothly track an object moving horizontally.

3. PMI – Another device that measures impairment based on the eye’s involuntary responses to light stimuli.


Complete list of companies involved in impairment testing, according to the National Workrights Institute:

1. Ambulatory Monitoring Inc.
Manufacture impairment testing systems for medical purposes. Do not offer systems for employment testing.

2. Assessment Systems, Inc.
Attempted to market psycho-motor impairment testing systems. Did not succeed and is now out of business.

3. Essex Corporation
Sold their impairment testing technology to Star Mountain Inc. Star Mountain has not yet introduced a product using this technology.

4. Eye Dynamics Inc.
Currently markets Safetyscope, an ocular based impairment testing system.

5. LC Technologies
Offers Eyegaze System, which is not for the industrial market.

6. Meridan Technologies
Company planned to enter the employment testing market, but never completed this effort. Is now out of business.

7. Performance Factors Inc.
PFI was the first commercially significant impairment testing company. Their Factor 1000 tested for psycho-motor impairment. Despite some success in the market, PFI has gone out of business. The rights to their technology have been acquired by T.A.S.A.L. (Capistrano Beach, CA), which has not yet introduced a product.

8. PMI Inc.
PMI markets the FIT system, which is based on the eye’s involuntary responses to light stimuli.

9. Predictive Safety, SRP
Offers the AlertMeter® test for cognitive impairment management and PRISM for fatigue risk management.
10. Systems Technology
Produces impairment tests, but not for the workplace.

Since the added pressures of COVID-19 and the rapidly changing workplace environment, this list may now need to be narrowed even further. Device-based impairment tests have become problematic due to heightened concerns over sharing devices between workers. These COVID-19 concerns further aggravated sentiments of distrust and suspicion that workers have towards wearable devices that track or monitor their biometrics. This has meant that device-agnostic impairment tests, such as those that run on apps, have emerged as clear market leaders.

fit-for-work tests-1

What are the benefits of impairment tests? 

Despite early struggles in bringing impairment tests to the workplace safety market, the benefits of using impairment tests have always been clear and profound. 

The main benefit of impairment testing is its ability to function as an agent of change towards a more positive workplace culture. This comes as an inevitable consequence of the smaller changes it sparks: 

1. Workplace impairment testing allows for more personal feedback.

At the end of each impairment test, the worker receives instant feedback concerning their state of mind and ability to work safely. 

This instant personal feedback empowers workers to take responsibility for their own safety, increase their awareness in identifying key human factors behind workplace incidents, and allow them to make better safety decisions. 

For example, one large transportation company reported that after implementing the AlertMeter® as a daily pre-shift impairment test, workers began utilizing that feedback to make lifestyle changes in order to arrive to work more alert and well-rested: 

“The feedback it gives to our employees motivates them to take responsibility for their off-time lifestyle behavior. They are definitely arriving more alert and more rested than they used to.” 

2. Workplace impairment testing prompts more safety conversations.

Many supervisors do not have the time to meet with each of their workers to make sure they are doing well mentally, physically, and emotionally each and every day. 

Even if they do have the time, they may be hesitant to be overly intrusive when they notice a worker may have something on their mind. After all, everyone has their personal problems and it’s difficult not to bring them into the workplace.

Impairment tests give supervisors an objective starting point to begin important safety conversations with just the right workers at just the right times. They promote and enforce better leadership qualities amongst supervisors and managers who are prompted into more effective engagement and communication with their workers. 

If a worker is unable to perform within their normal baseline on the impairment test, usually a supervisor is notified to investigate the cause of the issue. 

Since the impairment test will not reveal the cause of impairment, supervisors must utilize their communication and empathy skills to identify and address the problem in the positive and proactive manner. 

Ultimately, workers feel heard and supported. Supervisors save valuable time by focusing their attention where it’s most needed. The objective and non-intrusive nature of the test allows all of this to take place without any hurt feelings. 

An employee scored abnormally on two consecutive tests, triggering a notification to a supervisor. In the conversation that followed, the supervisor learned that the employee’s father had passed away the day before. (Stories from the Field). 

3. Workplace impairment testing provides increased insights into the underlying causes of human error.

Until modern day technology made workplace impairment testing accessible and efficient in workplaces, drug testing was the sole objective measure of the myriad factors behind human error. 

This means workplaces had a much narrower understanding of what constituted a “fit-for-duty worker.”  

As long as they had their training and didn’t have drugs in their system at the time the drug-test was taken, they were considered “fit-for-work.”

With the advent of impairment testing, workplaces suddenly received much more insight about a plethora of factors constituting worker impairment. Since you can’t manage what you don’t measure, they could now begin managing much more common sources of impairment like fatigue and emotional distress.

All of a sudden, accidents became a lot more predictable and preventable. 

An employee scored abnormally on two consecutive tests, triggering a notification to a supervisor. A conversation revealed that the employee was having difficulty seeing the shapes on the AlertMeter® screen with his new prescription glasses. The supervisor determined that the employee’s new prescription may not be appropriate, which could present a safety hazard. The supervisor advised that the employee return to the eye doctor. (Stories from the Field). 

4. Workplace impairment testing increases worker awareness about how to address underlying causes of human error.

With the instant feedback and insights provided by impairment testing, workers are now given greater responsibility and motivation to make better decisions concerning their own health and safety. 

Often, a worker who is severely impaired does not realize he/she is impaired.

This is typically apparent in drug and alcohol impairment. However, it is also true in cases where fatigue or emotional distress are involved. 

Willful blindness also plays a role here. There are many reasons why workers may feel compelled to turn a blind eye to cognitive impairment.

They need to earn their wages.

They don’t want to waste their days off. 

Sometimes they want to get their mind off personal problems.

Other times they’ve been conditioned by society and culture to appear tough and hardworking, and thus shrug off their mental or emotional struggles. “I’ll sleep when I’m dead” or “Early bird gets the worm,” for example, are popular mantras that fuel a dangerous disregard for cognitive impairment in workplaces. 

When companies start utilizing impairment testing, workers recognize daily the impact of cognitive impairment on their behavior. Once they recognize it as an important issue, and become more aware of its impact on them, they take steps to mitigate or avoid it. One study found that 20% of workers using impairment testing reported getting more sleep and drinking less alcohol. Workers have also reported spending less time watching Netflix late at night, and making greater efforts with their families to prioritize restorative sleep each night. 

“An employee came in one morning, struggling with the AlertMeter® game, so the supervisor asked him if anything was wrong. Apparently the evening before, his teenage son had to be taken to the emergency room because his son has some sort of terminal illness. The guy was in the hospital all night with his kid, and he shows up for work the next day. The supervisor asked him, ‘Why in the world are you here?’ The guy’s response was, ‘I’m the breadwinner of the family, I’ve got to earn a paycheck.’

This particular employee operates a 100-ton crane. Especially in the steel business, we’ve got a lot of tough guys out there. Prior to using the AlertMeter®, we probably would have never known his state of mind that day. When you think that through, I can’t tell you for sure an accident would have happened, but I can tell you we were able to take steps that day to keep an employee from hurting himself or others.” (Stories from the Field)

5. Workplace impairment testing increases empathy and trust amongst workers.

As mentioned, when workplaces have a way to measure previously undetected human factors, they not only become more aware of their own vulnerabilities but also more understanding of their coworkers’ vulnerabilities. 

Each shift, workers take their impairment test. Most of them do well and receive the instant feedback that they are cognitively fit-for-work. On occasion, one worker will not be able to perform on the test as he/she usually does. Workers gain visibility into the impacts of impairments like fatigue and distress on their coworkers, understanding that it can affect everyone at some point. Workers on close knit teams often share the source of their impairment with their coworkers–a sleepless night, an ill family member, some troubling news. This allows coworkers to empathize with one another, learn to prioritize each other’s mental and physical wellness, and be supportive instead of judgmental. 

Conversely, when all workers receive the pre-shift confirmation that they are fit-for-work, they feel greater trust for one another. In jobs when the fate of one worker rests on the ability of another to focus and do his job right, the ability to trust one another is a tremendous relief. Trust is so important to these workers that, if a worker is unwilling to take their impairment test one day, the others will actively encourage that they take it. 

Employees at one workplace started sharing their daily AlertMeter® performance results with workmates to prove that they are ready and able to work safely around each other.

When new middle management came on and were not debriefed on the AlertMeter® system, they did not understand its value and discarded using it. However, most employees who were using AlertMeter® before the new managers came on continued to use it and thought it was valuable, even though they were no longer being compelled to use it. Now, new manager orientation includes introduction to AlertMeter®. (AlertMeter® Case Study)

 7. Workplace impairment testing fosters safety through support rather than punitive measures.

Daily visibility into human impairment requires the implementation of supportive rather than punitive measures.

By adopting a top-level perspective on impairment, supervisors are forced to be supportive and communicate effectively in order to identify the cause of impairment. 

Cognitive impairment is complex and can involve a variety of causes. Working conditions, shift schedules, workplace culture, and team dynamics can all contribute to exacerbate worker fatigue, distress, and distraction. 

This means that instead of approaching impaired workers with a disciplinary mindset, supervisors are forced to recognize the degree to which factors outside the worker’s control may have contributed to his/her impairment. 

Ultimately, by being supportive instead of punitive, supervisors are able to create a learning opportunity for both the worker and for the management of the workforce. 

These learning opportunities can lead to improved shift scheduling, more timely breaks, more comfortable PPE, more access to water and/or coffee, and more comprehensive safety training and resources. 

“The trucking personnel now realize that,

‘We want them to be healthy, able to do their job while also having a life outside of work. There is an expectation that they are following sleep guidelines, maintaining healthy eating habits, and generally taking care of themselves. They’re not just workers with a pulse. We want them to be healthy and strong, have a lengthy career, and be able to spend time with their families outside of work'” (AlertMeter® Transportation Case Study).

8. Workplace impairment testing enforces a heightened sense of personal responsibility and accountability for safety.

As mentioned in number 4, the personal and objective feedback provided by daily impairment testing means that workers are compelled to take ownership over their own safety. 

Instead of blaming an incident on being too tired or being distracted by something, workers realize that these factors are now within their awareness and, therefore, within their control. 

A study cited by EHS estimated that between 60-80% of workplace accidents can be attributed to stress-induced issues like distraction. (EHS)

If a worker has daily insight into how factors like stress are contributing to his/her impairment, they begin to engage in countermeasures to alleviate this stress, including making lifestyle changes that promote their health and well-being.

“Q. Has [impairment testing] changed employees’ lifestyles overall?

A. Employees have told me that they’re taking better care of themselves now such as getting more sleep. One employee said his family traditionally had a BBQ every Sunday night with a fair amount of partying. They’ve changed it to Saturday night so he’s better rested for work.” 

By beginning each shift with this heightened sense of accountability and control over their own safety, workers are also more likely to approach all their daily tasks with safety top of mind. 

9. Workplace impairment testing reduces worker fear of speaking up or asking for help.

Number 7 discusses how impairment testing creates a culture of support rather than punitive discipline.

Number 4 discusses how impairment testing leads to increased awareness and understanding of the causes behind human cognitive impairment. 

These greater cultural changes in the workplace mean that workers are no longer afraid of speaking up or asking for help when they may be struggling with impairment. They understand that cognitive impairment impacts everyone at some point, and they must do everything in their own power to address it before it becomes dangerous. With safety top of mind, workers and supervisors work together to reduce risks and address problems in a proactive and unified manner.

“The interaction between our leadership team and our employees from a safety perspective has just gone through the roof. It has increased everyone’s safety awareness.” 

10. Workplace impairment testing can lead to a reduction in more invasive safety measures.

For example, one manufacturing company who adopted impairment testing with the AlertMeter®, reduced their drug testing costs by 90% by completely doing away with random drug-testing. Although other companies in other industries or locations may unable to alter their drug-testing practices in such a drastic fashion, an effort to also include non-invasive safety measures can help reduce dependency and negative attitudes towards invasive ones. By not only relying on invasive measures of impairment, workplaces can unwittingly send the message that control over workers’ lives and punitive action are essential components of your safety system. By diversifying and modernizing your safety program with a more positive and worker friendly safety measure, workplaces can drive home the point that safety is the goal, not control or discipline. The communication and empathy sparked by the implementation of an impairment test like the AlertMeter® can further be used as an opportunity to address worker concerns and dispel negativity towards your other safety practices. 

11. Workplace impairment testing can help reduce negativity and resentment among workers.

Despite the fact that new technologies are often met with suspicion and hesitance among workers, impairment tests have been accepted with surprising positivity even in their early days. 

According to research by the National Workrights Institute: 

  • 100% of employers who used impairment testing considered their experience successful.
  • 82% of employers found that impairment testing improved safety.
  • 90% of employees accepted impairment testing.
  • 87% of employers found impairment testing superior to urine testing.

These survey results are indicative of the rapidly changing attitudes towards drug-testing in light of cannabis legalization, increased social and cultural pressures on workplace safety, and the availability of less invasive technologies that achieve more insight in less time. 

Even before impairment tests were a reality, using drug-testing as a safety procedure seemed to be quickly getting outdated and ineffective. 

So, how do companies who use impairment testing leverage it against their corporate and legal drug testing policies? 

How do the two fit together? Do they fit together? 

By recognizing the strengths and weaknesses of both impairment testing and drug testing, you can implement a solution in your workplace that drives safety and positivity forward without neglecting your responsibility to the law. 


How does impairment testing compare to drug testing? 

Drugs vs. Impairment tests

In “Drug Testing vs. Impairment Testing: What Makes a Safer Workplace?”, we cite a variety of reasons drug-testing falls short in creating a positive safety culture and serving as an effective safety procedure: 

  • “Most people who have accidents on the job are not drug users, and drugs have nothing to do with [most] accidents. Most accidents are caused by fatigue or alcohol” (Maltby).
  • Drug testing is not a screen for alcohol intoxication, and many employees are randomly tested for drugs but may drink regularly or to excess. Though they may not be acutely or visibly drunk at work, they may sometimes be hungover, and a random drug test doesn’t prevent them from undertaking safety-sensitive work.
  • Drug testing cannot identify heightened safety risk before it culminates in an accident. But pre-task or pre-shift impairment testing can do this, and thus allow for supervisor intervention when such circumstances arise.
  • Pre-employment drug screens don’t detect drug use on the job, nor do they dissuade it, and thus do not improve safety. Instead, job applicants merely take a break from using drugs so they are clean for the pre-employment drug screen.
  • “It may be perceived as politically expedient to demonstrate that ‘something’ is being done [but] has proven to be ineffective, costly and potentially prone to ‘false positives’—with negative repercussions for [employees] whilst giving the false impression of safety” (European Cockpit Association).
  • “The implementation of drug testing programs can lead to resentment and a subsequent increase in grievance rates, deteriorating labor-management relations, decreased morale, and difficulties in attracting and hiring qualified candidates” (Seijts and O’Farrell).
  • “Employers know that [drug testing] doesn’t mean anything. Anyone who smokes pot will just stop for a few days. It’s an empty ritual that nobody wants to be the first to give up,” (Maltby). 

Despite its flaws, drug-testing remains an essential component of company policy, and is further enforced by state and federal laws. Companies that have a “zero-tolerance” policy rely on drug tests as an objective, scientific measure to enforce these policies. Due to its strict enforcement and punitive nature, drug-tests can keep habitual drug users from being hired to safety sensitive roles and get them promptly fired if proof of use emerges later. Although workers who are experienced with drug-tests have found ways to circumvent getting caught, drug tests are still largely effective at dissuading heavy drug use during employment. 

Further, although imprecise in their timeframe of measurement, drug-tests are highly accurate at detecting the presence of specific substances in a worker’s system. This often means that the cognitive detriment caused by non-illicit substances such as over-the-counter medications are overlooked. However, it also means that workplaces can be confident as they filter out heavy drug users from amongst their workforces. 

Drug-testing has a clear focus and objective in the workplace and, despite its shortcomings and oversights, is a well-established policy that is here to stay. However, this doesn’t mean that it can’t be improved upon and complemented by a more proactive and positive safety procedure like impairment testing. 

Impairment testing can help overcome the flaws of drug-testing because: 

  • Impairment testing focuses on workplace rather than leisure behavior. In other words, impairment testing works to prevent safety risk because it “focuses primarily on impairment, not on the cause of impairment. The objective of [impairment] testing is to assess fitness for work, not to detect drug use.” (Workforce)

  • Impairment testing is non-invasive and protects employee privacy. It also protects employees who use medical marijuana from the flaws of drug-testing, which can lead to false positives. 

Impairment Tests 
Drug Tests
  • Daily, as often as needed (before shifts, after lunch, before critical tasks, etc.)
  • Random or post-accident
  • Non-invasive (no body fluids or hair)
  • Requires hair/urine/saliva sample
  • Positive
  • Punitive
  • Proactive
  • Reactive
  • Takes as little as 60 seconds
  • Disruptive of work (Specimen collection, delivery, and results could take days to weeks.) 
  • Instant feedback
  • Feedback delayed until results are processes
  • Has shown to influence safer behaviors at home and at work
  • Falls short in influencing healthy and safe behavior 


Depending on your company policies and local laws where your company is situated, your implementation of impairment testing may either strongly curb your use of drug-testing or be utilized entirely independent of your drug-testing policies. 

For example, one manufacturing company located in Colorado was able to reduce the cost of drug-testing by 90% by replacing all random drug tests with daily AlertMeter® use. At the same time, their safety metrics improved substantially. They reduced worker’s compensation claims by 70% across 2 years of AlertMeter® use. They also improved productivity by 11% and reduced employee turnover by 35%.

Other companies in other locations or industries may not have such flexibility with their drug-testing policies. There, they use impairment testing to complement existing procedures rather than to replace them. Sometimes, impairment testing provides the real-time insight needed to get a supervisor’s attention and prompt a more thorough assessment of impairment based on company policies.

The following stories from AlertMeter® use at various companies portray how impairment testing has been shown to successfully complement zero-tolerance policies and drug-testing practices: 

When employees in a division of a large company received word from management that they would begin using AlertMeter®, an employee came forward to admit having a substance abuse problem and chose to seek help for his addiction.

An administrative employee scored abnormally on consecutive tests and admitted to having inadequate sleep and to taking cold medications. The supervisor observed unusual and inconsistent behavior from the employee, who still could not score normally on a third attempt. The supervisor referred the employee to human resources. (Stories from the Field). 

Now that you are more familiar with what impairment testing is; what forms it takes; how it compares with and complements drug-testing policies and procedures, you can begin to evaluate whether it is a viable option for your company. 


Is impairment testing right for your company? 

When deciding whether impairment testing will be successful at your company, consider the following: 

1. What industry is your company in?

Impairment testing has been successfully implemented in wide range of safety-sensitive industries such as: aviation, transportation, manufacturing, construction, mining, oil and gas, utilities, healthcare, and more. 


2. What is the size of your company?

Impairment testing is beneficial in different ways depending on the size of your company. In small companies, supervisors may have greater visibility and communicate more often with their workers than in large companies. Despite this, impairment testing is used as a way to identify sources of impairment that are subtle or easily masked. Fatigue, for example, is difficult to identify in its later stages even by the worker himself. An objective measure that can assess and monitor the progression of fatigue throughout a shift can prove life-saving in such a situation. Further, impairment testing in small companies is helpful in that it enforces personal responsibility for safety despite a lack of the stiff oversight, hierarchy, and discipline that are enforced by larger companies. Impairment tests can provide the structure or routine necessary to consistently prioritize safety even within the more relaxed and intimate team environment often seen in smaller companies. 

In larger companies, impairment tests are a great way for overburdened supervisors to get a quick glimpse into the fitness of their entire team. Impairment tests with automated alerts, such as the AlertMeter®, instantly notify supervisors via text or email when a worker needs their attention. This ensures an efficient and effective use of the supervisor’s time and gets workers the help they need much quicker than if they had to wait until the next supervisor to walk through and notice them. As mentioned, a worker who is dangerously impaired is often unaware of his/her state and thus would be unlikely to seek attention on their own. 

3. Where is your company located? 

Impairment tests have been successfully implemented everywhere from the gold mines of Siberia, to the coal mines in South Africa, to hospitals in England, and the truck stops of Midwestern United States. 

Thanks to modern technology, impairment tests can be integrated into telematics and timekeeping systems and can be used even on sites with limited internet service. 

4. What is the language/education level of your workers? 

The language and education level of your workers are irrelevant when implementing impairment tests because the tests are usually based either on monitoring biometric indicators such as pupil movement; or in the case of AlertMeter®, an easy to use game-like shapes test that doesn’t require specific language skills. Technological savviness is also irrelevant on the AlertMeter® because workers establish their own personal baselines that control for their level of familiarity and comfort with apps and phones. 

5. What are your workers’ shift schedules like? 

Impairment tests are a great safety boost for shift-workers. Especially long or graveyard shifts, as well as workers on rotating shift schedules can benefit from the additional visibility provided by impairment tests. Workers can suffer from reduced alertness and cognitive impairment at the beginning of early morning shifts before they’ve had time to sufficiently wake up; during the circadian dip after lunch; and at the ends of shifts. 

One study that compared cognitive impairment due to alcohol intoxication with cognitive impairment due to fatigue, or “sustained wakefulness,” found that, 

“Sustained wakefulness may carry a risk comparable with moderate alcohol intoxication since approximately 50% of shift-workers on 8 hour shift patterns typically spend at least 24 hours awake on the first night shift in a roster (Knauth et al, 1981). Furthermore, the highest level of impairment observed in this study (0.096% BAC) would occur at the end of a typical night shift (i.e. 0600-0900h) and would frequently coincide with the trip home for many shift workers.” 

The study notes that this BAC level (which, by the way, is higher than the driving limit) would be considerably higher for a worker on a rotating shift schedule who didn’t have a chance to adjust to his/her new sleeping schedule and get sufficient restorative sleep before coming into work:

“Several studies have reported that the performance decrements, reduced alertness and fatigue reported by night shift workers is greater on the second and third night shift (Tilley et al, 1981). If this is the case, then it may be reasonable to assume that the alcohol impairment equivalent on these nights may be even greater than reported here for the first night.”

6. What do worker’s unions think about impairment testing? 

Since impairment tests put the focus on worker well-being rather than catching wrong-doing, they are usually welcomed by unions. 

If your company is considering impairment testing, it is important to involve union leaders in early conversations to ensure they are well-informed participants in the discussion. 

Some aspects of impairment testing that union members appreciate are: 

  • not invasive
  • can lead to more effective hiring practices
  • helps workers keep each other safe and accountable
  • supervisory access to data can be configured to minimize management involvement and maximize management by union leaders. 

In fact, union members at one site volunteered to try out impairment testing with the AlertMeter®. After realizing that the nature of impairment testing was not punitive, total worker participation at the site increased from 10% at the beginning of the pilot to 95% three months later (from 40/400 original volunteers to 340/400 volunteers). 

Peer pressure was also thought to play a role in the vast growth in participation. Workers who took the test and confirmed that they were fit-to-work wanted their coworkers to also confirm their fitness for work so that they could trust one another with their safety. 

For a list of union FAQs about AlertMeter®, click here. 

7. Most importantly, what does your safety culture look like now and what are your objectives going forward?

Companies who adopt impairment testing have stated one or several of the following objectives in driving their decision: 

1. We want to become more proactive and positive in our safety culture. 
2. We just had an accident we weren’t able to predict. 
3. We need to combat fatigue better. 
4. We need to address drug and alcohol impairment in real-time.
5. Cannabis was just legalized and we’re looking for a way to adapt. 
6. We need more realistic hiring practices to overcome labor shortages. 
7. We are trapped in an accident cycle.
8. We need to reduce our error rate.
9. We want to improve productivity.
10. We want to address invisible safety threats (personal family crisis, emotional distraction, change in medications, etc.).
11. Our supervisors don’t have enough time to check in on everyone every day, so we need more automated, timely insights.
12. We are looking for something new and innovative to keep us competitive in safety. 


Impairment testing technologies have come a long way in the last few decades. 

Although there is a rapidly growing demand for comprehensive insights and positivity in modern workplaces, there is a general lack of awareness surrounding impairment tests. 

Impairment testing solutions that are well-suited for the workplace have only emerged quite recently, and the market is mostly comprised of wearable tracking devices and the AlertMeter® app. 

With COVID-19 compounding concerns over cognitive impairment in the workplace (see COVID-19 and Absenteeism in the Workplace: Causes and Costs) and also making it more unlikely for wearable or shared devices to be safely shared amongst workers, the AlertMeter® has cemented its position as the most viable and most popular workplace impairment solution on the market. 

Workplaces that have implemented AlertMeter® during this time have seen tremendous improvements in overall safety metrics as well as safety culture:

  • Decreases in worker’s compensation claims
  • Decreases in safety incidents
  • Decreases in accident severity 
  • Decreases in costs of accidents
  • Decreases in turnover rate
  • Decreases in error rate
  • Increases in safety awareness
  • Increases in safety compliance
  • Increases in worker alertness 
  • Increases in productivity 
  • Increases in worker accountability and responsibility
  • Increases in communication
  • Increases in trust and morale 


Achieving similar results requires companies to raise awareness about what impairment testing is and what it involves. This means educating workers, unions, company executives, and fellow managers so that everyone is well-informed and stands unified behind the decision. It has been shown that any hesitance or pushback against the implementation of impairment tests arises due to a lack of understanding. 

For example, companies who use AlertMeter® often report that any workers who are initially opposed to the idea of impairment testing end up fully embracing it once they recognize how it works. An AlertMeter® case study at one construction site reported: 

“When new middle management came on and were not debriefed on the AlertMeter® system, they did not understand its value and discarded using it. However, most employees who were using AlertMeter® before the new managers came on continued to use it and thought it was valuable, even though they were no longer being compelled to use it. Now, new manager orientation includes introduction to AlertMeter®.” 

When a company’s goal is to increase safety and improve safety culture, impairment testing with AlertMeter® has never disappointed. If your company, your executives, your workers, and your fellow managers stand united behind the belief that safety is and always should be the number one priority, you’re ready for AlertMeter®.

To get pricing and more information, schedule a demo:
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