An oil refinery with miles of pipes, a nut-processing plant, a state-owned fish hatchery, a microchip manufacturer, a university research laboratory, and an amusement park – to most, these enterprises have little in common. They are all separated by geography and engaged in vastly different spheres of business. However, they, and approximately 3,400 other facilities across the United States, are covered by a national security program aimed at preventing terrorists from acquiring chemicals to use in an attack — the Chemical Facility Anti-Terrorism Standards (CFATS) program.

Terrorists have a long history of being attracted to the use of chemicals, given their potential to inflict mass casualties when misused. Facilities with chemicals continue to be targeted by terrorist groups around the world looking to cause releases onsite or acquire materials to be used in future attacks offsite.  The CFATS program was born in 2006 when Congress, recognizing the threat, directed the Department of Homeland Security to work with stakeholders to close security gaps at high-risk facilities.

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Chemicals are essential to a broad swath of American businesses, and with few exceptions, the CFATS regulation applies to any facility holding designated threshold amounts of "chemicals of interest." The universe of high-risk facilities is diverse and not limited to those sites traditionally considered part of the chemical industry. Take that nut-processing facility mentioned earlier, for example. While pistachios and almonds may not spring to mind as potential terrorist weapons, food processing requires the use of high-risk chemicals to clean equipment and provide refrigeration. When used properly, these chemicals are an important part of commerce — but in the wrong hands, they can be deadly.

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For more than 11 years, the CFATS program has worked with companies to implement security measures that reduce the risk posed by more than 300 potentially dangerous chemicals. The program focuses on preventing chemicals being stolen, diverted, sabotaged, or deliberately released by terrorists or other bad actors. CFATS has assessed risk at over 40,000 chemical facilities in the United States, with only approximately 3,400 of them considered to be at the highest risk of attack or exploitation.

From perimeter controls to cybersecurity measures, CFATS has enhanced security at high-risk chemical facilities. Most important, given the diversity of the businesses considered high-risk, CFATS' success has been based on flexibility and the program's commitment to working with businesses to meet the regulation's requirements. We have built a regulatory environment that is grounded in continuous, constructive dialogue with industry stakeholders — a cooperative approach that is on display this week in Philadelphia as government and industry stakeholders gather to discuss security-related best practices and CFATS policies.

This year marks the expiration of CFATS authorization. Without action, we risk losing ground and rolling back the progress we've made in securing our nation's highest-risk chemical facilities. Legislative action is needed to reauthorize this vital national security program. Seventeen years after 9/11, we still live in an environment that gave rise to CFATS, and the threat is as real as it has ever been. At the Department of Homeland Security, we are committed to working with Congress to reauthorize CFATS for the long term and to working with our stakeholders to continue to protect our communities and our nation from the threat of chemical terrorism.

David Wulf is the director of the Infrastructure Security Compliance Division at the U.S. Department of Homeland Security.