Critics of behavior-based safety (BBS) claim injury prevention requires a holistic, system-level approach. Behavioral observation and feedback among line workers is not enough. Plus, management must not use BBS as an excuse to shirk its responsibilities, such as developing a more user-friendly workplace and maintaining accountability systems that keep safety integral to daily work activities.

Guess what? I agree. Actually, I've never heard a BBS trainer or consultant disagree with these arguments. BBS reflects a philosophy and a set of tools that supports any ongoing safety initiative - especially those that are holistic, system-focused, and management-driven.

A valuable tool

BBS's basic tools can improve the behaviors of everyone - from the worker performing hands-on activities to the supervisor overseeing the entire effort. These tools are not limited to safety undertakings, but are pertinent to all aspects of an organization's mission statement.

This is the first of a two-part series on one of the most valuable BBS tools - the critical behavior checklist (CBC). My descriptions and examples will address safety, but this tool is applicable to everything people do at work. Performance of any sort cannot improve without behavior-based feedback, and feedback is often most instructive when linked to recorded observations.

Simply put, the CBC consists of a list of some of the specific behaviors required to complete a task effectively. You can also check whether each behavior is performed "competently" or "incompetently." For safety applications, this column distinguishes between "safe" and "at-risk." Definitions of "competent" vs. "incompetent" or "safe" vs. "at-risk" are developed through structured group discussions and consensus building.

Developing a practical CBC acceptable to all potential users is an invaluable process. If done right, it instills a sense of team ownership, as well as self-efficacy and personal control. These positives increase when everyone agrees to use the CBC, and are integrated into the culture whenever the CBC is used to observe coworkers and provide behavior-based feedback.

I've discussed optimal ways to observe others and give interpersonal feedback in prior ISHN articles (see, for example, my columns for December 1993, July and August 1996, and May 1999). However, I have not previously addressed the challenge of selecting the behaviors for a CBC.

What's critical?

Don't take developing your CBC lightly. When you decide what safety-related behaviors are "critical," you define aspects of a job that require the most attention and mindfulness. These are the behaviors that people will hold each other accountable to perform safely.

Sources for deciding which behaviors to include on a CBC include: injury records, near-hit reports, job-hazard analyses, standard operating procedures, rules and regulations, your site's medical staff, or anyone else who maintains injury statistics for your organization. Talk to your workforce. Employees already know a lot about their own safe and at-risk work practices. They know which safety rules are ignored. They know when a near-hit has happened to them or to others because of at-risk behavior.

Evaluating relative risk is key to selecting critical behaviors. Which behaviors create the most risk for injury?

Estimating risk

Risk associated with a particular behavior depends on exposure, severity, and probability. Discussing each of these dimensions facilitates the process of developing and refining your CBC.

Exposure: Every time an at-risk behavior occurs, someone is exposed to potential injury. The more often this behavior occurs and the more people performing it, the greater the exposure. For example, lifting a load greater than 40 pounds might not be very risky if done once, but multiply this risk by numerous employees making several lifts per day and you gain a different perspective.

Duration also contributes to risk exposure. The longer one carries a 40-pound load, the greater the exposure. The longer one resists using personal protective equipment (PPE), the greater the exposure. Conversely, one brief instance of donning certain PPE, from a hard hat to a vehicle safety belt, reduces risk exposure for the entire duration of usage.

Severity: Behavioral risk also varies according to the severity of possible harm or injury. What's the worst scenario that could occur from a particular at-risk behavior? A fatality? Multiple deaths?

Sometimes history provides harsh lessons. Certain at-risk behaviors have contributed to plant explosions, vehicle crashes, asphyxiations, and to humans crushed by equipment. These are usually included on a CBC, unless their occurrence is extremely rare, making the exposure very low.

Probability: What's the probability a behavior will result in an injury? This is a subjective judgment, the most difficult risk assessment to make. Consider the act of lifting. By counting people and daily opportunities to lift per person, you can get a good estimate of exposure. It's not hard to imagine the worst possible outcome of a severe back injury. You likely know someone who has suffered a slipped or herniated disc.

But how probable is it that lifting a load greater than 40 pounds will cause a back injury of any severity? Many factors come into play - the age and physical strength of the lifter and various behavioral aspects of the lift. When lifters hold the load close and bend their knees, the probability of a back injury is greatly reduced. That's why a CBC on lifting behavior includes several specific behavioral components.

Let's look at the use of fall protection. The severity of a fall from three stories is obvious. Exposure is easy to estimate by counting the number of people working at this height and multiplying the total by the average duration per employee per day.

But what about the probability of someone falling from a three-story height?

Again, numerous factors are involved, including the nature of the work and the physical and psychological state of the worker. Since these factors are impossible to appraise for an individual, it's best to assume the highest risk level for each relevant factor and use your best judgment. Assume the probability of falling is fairly high for the average worker, and put more stock in your estimates of exposure and severity.

Next month I'll address another aspect of developing or refining a CBC - the relative convenience of the target behavior. This determines the number of behaviors to include on a CBC and what kind of CBC scores can be expected. This dimension can also lead to constructive discussion and decision-making about environmental changes that can make a work setting more user-friendly or ergonomically sound.


Three characteristics of an at-risk behavior determine its relative risk - exposure, severity, and probability of occurrence. You can remember this as the "ESP approach" to estimating behavioral risk.

Exposure fluctuates according to the frequency and duration of the at-risk behavior for all employees at a work site. It is the easiest of the three risk factors to estimate.

Severity is judged by visualizing the worst possible consequence that could result from the at-risk behavior.

Probability is most difficult to estimate because so many environmental and individual factors influence the likelihood of an at-risk behavior resulting in an injury. As with severity, a conservative approach is recommended. Assume bad luck, meaning all the factors that could increase the possibility of injury are in place, from unfriendly environmental conditions to an individual whose attention periodically deviates from the task.