The Bathtub Effect: Why Safety Programs Fail
Webb, David A., Management Review
What do the fatal chemical release at Bhopal and the Exxon Valdez oil spill have in common? Both have focused political and public attention on how companies manage environmental, health and safety issues wherever they do business around the world..
The unfortunate truth is this: Despite the best efforts of government and industry to improve environmental, health and safety performance, major industrial accidents are just as likely to occur today as they were 10 years ago. Yet over the same period, society's expectations for environmental, health and safety management have risen.
While expectations are increasing and companies are doing their best to improve, businesses are also in the grip of an all-pervasive drive to do more with less throughout their operations. From the plant floor to the highest ranks of corporate management, companies are redefining how people work and learning how to do more with fewer people and at less expense.
Environmental, health and safety management hasn't been exempt from this drive for greater efficiency. In the past, companies often achieved good safety performance through overdesign, large staffs and ever-expanding budgets. The railroad industry, for example, used to meet high safety standards by building locomotives and carriages with massive chassis and employing enormous staffs to check and double-check everything.
Today, overdesign and overstaffing are no longer viable approaches to good performance. In the drive to bring costs down, mass transit systems have reduced energy costs by making rolling stock as light as possible, and they have reduced staff by developing computer control and safety systems and automatic trains that operate without drivers. Many other industries have also made broad changes in the way they manage environmental, health and safety issues. But they have not yet seen solid, longterm gains in performance.
The discovery by environmental, health and safety managers that new approaches sometimes yield disappointing results is hardly unique to their field. In the equipment maintenance field, for example, when equipment is new, design and manufacturing defects lead to high failure rates. Then, after the kinks have been worked out, failures fall to a low rate for a few years, only to begin to climb steadily as the equipment ages. Charted out on a graph, this curve resembles a bathtub (see Figure 1).
Stuck in the Bathtub
Maintenance programs seek to stay out of the bathtub by finding ways to keep the failure rate as low as possible. Their goal is a performance curve that isn't a bathtub at all, but a steep drop followed by consistently low failure rates (see Figure 2).
The ideal environmental, health and safety management program has a similar profile. Accident rates fall quickly to an acceptable level and stay there. In reality, performance profiles all too often develop unsatisfactory curves--bathtub curves. Let us look now at the most common unsatisfactory performance profiles and the reasons they happen. Managers who understand these common failings have a better chance of keeping their programs out of the bathtub.
Shallow Tub: Incomplete Coverage
Many programs reduce some types or locations of accidents, but fail to provide complete coverage for all causes of accidents and at all locations or divisions within the organization.
When improvement only shows reductions in certain accident types, key pieces of the environmental, health and safety program are often missing. For example, the environmental, health and safety program of a metals-pressing company did not cover hazardous chemicals. The company assumed that hazardous material safety was irrelevant in its mechanical operations, despite the fact that several of its degreasing agents were highly flammable liquids. Luckily, the oversight was discovered before a serious accident occurred.
All too often, the environmental, health and safety program leaves out whole departments or significant activities. …