The standard, Prevention Through Design: Guidelines for Addressing Occupational Hazards and Risks in Design and Redesign Processes, is part of a seven-year project begun in 2007 by the American Society for Safety Engineers (ASSE) and the National Institute for Occupational Safety and Health (NIOSH). It provides a detailed guide for organizations on how to implement PTD through their safety and health management system.

Bruce Main, vice-chairperson of the guidelines committee, said the goals of the standard are to “achieve acceptable risk levels; prevent or reduce occupationally related injuries, illnesses and fatalities; and reduce the cost of retrofitting necessary to mitigate hazards and risks.”

The standard, which follows ISO format and has been endorsed by the American National Standards Institute (ANSI), takes effect January 2012. A range of U.S. organizations, from industry and labour to government agencies and professional organizations, participated in the project.

The guidelines cover in detail the implementation of PTD through the four stages of risk management: pre-operational (initial planning and design); operational (identification of risks and remedial action); post-incident (investigation); and post-operational (demolition or reusing operations).

One of the key sections of the standard, dubbed ANSI/ASSE Z590.3-2011, deals with the design safety review, the tool by which the PTD system — including inspection and test protocols — is implemented. A company must do at least one design safety review of their system, said Main, president of Design Safety Engineering.

“Companies find that, the more they do this, the more they are able to influence the design early and end up having more design reviews that focus particularly on safety,” he said.

Another important topic is risk assessment, and the standard describes eight effective techniques. Main says managers must select one, establish parameters and know how to identify hazards. They must also consider different failure modes: “What are the different causes that can lead someone to be in harm’s way?” he says.

The guidelines describe other aspects of a good safety assessment, including assessing the severity of consequences, understanding the hazard control hierarchy, assessing residual risk, documenting results and following up.

Paul Schulte, NIOSH director, education and information division, says the concept of PTD means incorporating occupational safety principles into the design phase of every level of work — from facilities through methods and equipment to the molecules in multi-molecule products — to minimize hazards and risks. In looking at design, PTD principles focus on the worker and how a specific process or machine is used.

NIOSH decided to promote the PTD concept, he added, because it is aimed at eliminating risk. It is thus the most effective of all controls in the “hierarchy of prevention,” a model that ranks various controls on the basis of effectiveness. At the bottom of the pyramid is PPE, while middle levels include administrative and engineering controls and at the top is “elimination through design or redesign.”

“PTD is the most effective level in the hierarchy of controls. It’s also a level at which there can be great financial value, when you look at the whole picture of the impact of bad designs versus good designs,” he said.