Visual Dust Hazard Analyses Using Bowties

Bowtie diagrams help workers quickly visualize and manage threats that can cause uncontrolled ignition of dust, as well as identify the barriers that prevent ignition.

The harm and asset damage that a dust explosion can cause have been known for centuries. However, knowing about an issue is not the same as adequately understanding and addressing it.

Just as a conventional process hazard analysis (PHA) divides the process into nodes, a dust hazard analysis (DHA) breaks the plant into sections that are systematically challenged to determine if explosion or fire hazards exist. For dusts, this includes identification of ignition threats.

In this article, we draw on our complementary experience in DHA application (1) and bowtie implementation (2) to present a novel approach to scenario visualization and asset management using bowtie diagrams.

In a bowtie diagram, the dust ignition scenarios and safeguards are shown graphically, which offers significant communication benefits over a more traditional spreadsheet format. In addition, bowties offer an easy way to illustrate how ignited particles can travel and cause an uncontrolled ignition in downstream equipment. Improved visualization can be particularly helpful in facilities or countries where English is not the primary language and/or where the employees are not familiar with risk terminology.

This article demonstrates how bowties are an effective tool to engage less-technical stakeholders. It describes a robust framework to ensure that the ignition risks are understood and the controls are properly implemented, operated, and maintained...