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When someone mentions the hierarchy of controls, occupational and environmental health and safety professionals likely think of NIOSH's pyramid and its five levels of control strategies: elimination, substitution, engineering controls, administrative controls, and personal protective equipment.

A newly published white paper by AIHA, titled Hierarchy of Controls, reorients OEHS professionals' approach to the hierarchy of controls and illustrates effective application of the HoC to address workplace hazards. NIOSH's pyramid is just one version of a flexible and expansive concept that can be adapted to the specific risks and hazards found in any workplace. For example, the HoC model shown in Figure 1 enhances the pyramid and illustrates the efficacy of various controls in a way that helps users select appropriate strategies to address known hazards.

The White Paper’s Role for OEHS Professionals

OEHS professionals will find that the new white paper revitalizes risk management, increases understanding of risk treatment options, offers HoC models fitting the needs of many organizations, and provides useful tools for prioritizing, valuing, and implementing risk management strategies. The HoC is integral to the ARECC (anticipate, recognize, evaluate, control, and confirm) decision-making framework, exposure risk assessment and management, and prevention through design (PtD), as shown in Figure 2.

An expanded understanding of the HoC enhances an OEHS professional’s risk management options. The HoC white paper aligns with AIHA’s Competency Framework: Understanding and Applying ARECC to Occupational and Environmental Health and Safety and complements the process outlined in ISO 31000, Risk Management—Guidelines in two ways (Figure 3). First, the white paper’s in-depth discussion of various levels of risk treatment and their applications expands an OEHS professional’s array of possible control solutions for a given hazard. Second, the white paper explains and links to resources for developing cost-centered business cases and focused implementation strategies that serve the risk treatment element of ISO 31000.

Application of the HoC

The white paper is intended to expand OEHS professionals’ ability to conceptualize controls beyond action- and worker-dependent options, including warnings, procedures, and PPE, which are ranked lowest on the HoC in terms of effectiveness and reliability. Design considerations, including pre-installation control of risks, substitution of lower-risk elements, and simplification of work processes, are more effective in ameliorating risk. If OEHS professionals take the risk treatment options outlined in the HoC white paper into account during the design of new processes or products, they may eliminate hazards before any workers are exposed.

When this PtD approach is not possible due to urgency, interim protection, or other factors, the white paper describes a process for implementing multiple controls to decrease workers’ risk of hazardous exposure to acceptable levels. The white paper provides OEHS professionals with the tools they need to compare the cost-benefit ratios for such situations and helps them develop and champion capital projects that will cost-effectively reduce risk in workplace process flows. Table 1, found on page 9 of the white paper, illustrates the value of brainstorming controls at all levels of the hierarchy when addressing risk and provides an example of a roadmap for effectively controlling an identified risk.

Development of the white paper began when AIHA’s Social Concerns Committee called on members to address the lack of resources providing high-level discussions of the HoC. The committee intended for the resulting document to help OEHS professionals apply the HoC. It also hoped the document would enable the AIHA Board of Directors, staff, and volunteer groups to act quickly and consistently when reviewing potential laws, regulations, or consensus standards and to consistently relate the HoC to OEHS issues facing workers and the public. Because of the white paper’s importance to multiple AIHA initiatives, the project team that developed it received the 2024 President’s Award for Distinguished Service to AIHA. As AIHA’s highest honor, this award recognizes members and teams that advance the OEHS profession through distinguished and exemplary service and support the association’s mission and vision through unique technical and professional contributions.

The HoC white paper was written for early- and mid-career OEHS professionals. It addresses the use of big data and sensor technology, emphasizes communication of OEHS concepts, and supports exposure banding. Other topics it covers include the changing workforce and, particularly, how the HoC complements Total Worker Health approaches. In short, the white paper is meant to help readers improve and implement more effective OEHS risk management in the 21st century.

Hierarchy of Controls may be downloaded as a PDF.