Recent chemical emergencies on the West Coast have raised questions about the safety of massive industrial tanks. While experts note that failures are exceedingly rare when tanks are properly maintained, two major incidents occurred within a week: a tank rupture at a Washington paper mill killed two people and possibly nine others, and a chemical tank overheating in Southern California led to the evacuation of about 50,000 people.
Safety Standards for Chemical Tanks
Chemical engineering professor Stephen Kmiotek from Worcester Polytechnic Institute stated that almost every industry uses chemical tanks, and they are generally safe if companies follow building, maintenance, and inspection standards. The failure rate is about one per million tanks per year. However, proper maintenance is crucial, especially for older tanks and those containing highly caustic substances like the white liquor involved in the Washington incident. Valves need frequent replacement. Authorities are still investigating the tank's age and valve replacement history.
Regulatory Responsibilities
Regulation involves multiple levels. The U.S. Environmental Protection Agency and the Chemical Safety Board are investigating the Washington incident. State agencies, such as the California Division of Occupational Safety and Health and the Washington State Department of Labor and Industries, oversee inspections. Local fire marshals and hazardous materials teams also play roles. In Washington, the state agency often investigates based on complaints or incidents due to a high number of chemical sites relative to inspectors.
Federal Oversight
Federal regulators require facilities storing hazardous chemicals to maintain safety data sheets and share information with local officials. The Occupational Safety and Health Administration has Process Safety Management standards for highly dangerous chemicals, including inspections, training, and emergency planning. It is unclear if the Washington paper mill falls under these protocols.
Public Health Concerns
Public health expert Stephen Lester expressed concerns about unclear exposure standards for chemicals after spills or explosions. Workplace exposure standards are based on an average adult male and do not account for children, the elderly, or immunocompromised individuals. Without health-based guidelines, decisions about acceptable exposure levels rely on individual judgment.
