Recent adjustments to the Department of Homeland Security’s Chemical Facility Anti-Terrorism Standards (CFATS) program have simplified the process of completing a risk-assessment, known as a Top-Screen, and could result in changes to how an ammonia refrigeration facility is categorized under the program’s tiering system.

DHS, in conjunction with IIAR, recently held a webinar that focused on when and how industrial ammonia refrigeration facilities must report to DHS. Presented by Kelly Murray, the Standardization and Evaluation Section Chief for DHS, the webinar unveiled a revamped tiering methodology and a streamlined Top-Screen model.

During the rollout, DHS has reached out with notifications sent to the 27,000 facilities of chemical interest in the country. DHS inspectors have met with local emergency planning committees and visited with chemical manufacturers and distributors. Ammonia refrigeration facilities with more than one percent concentration and 10,000 pounds of ammonia are required to submit a Top-Screen.

“Some facilities don’t realize they are supposed to report, so we are trying to assist them in adhering to the program,” Murray said. “We’re taking a softer approach in helping them understand their obligations before any enforcement [takes place].”

DHS identifies a facility’s level of risk using information submitted by facilities through Top-Screen, which takes into account vulnerability, potential consequences and the threat of a terrorist attack. Facilities are then placed into one of four tiers, with Tier 1 representing the highest risk. Under the revised tiering methodology, which was reviewed by industry and government experts, facilities can move from higher to lower tiers, or vice versa. They can also become un-tiered or newly tiered.

A facility’s tier can change based on a revised Top-Screen submitted to DHS. For example, a tier determination may change if:

Facility operations change significantly. This could include the removal or addition of chemicals of interest, changes in operations or processes, and/ or changes in threats or vulnerabilities. Such changes typically would be sitespecific and will be reviewed on a caseby-case basis. When a facility makes a material modification to its operations or site, it must submit a revised Top-Screen within 60 days. Following the submission, DHS may require the facility to submit supporting documentation.

Resubmission of a Top-Screen reveals changes in threat, vulnerability or consequence. Facilities with approved Security Vulnerability Assessment (SVA) and Site Security Plans (SSP) are required to resubmit Top-Screens every two years for Tier 1 and 2 facilities and every three years for Tier 3 and 4 facilities.

In rare cases, DHS considers new information about a site, chemical, threat or process that warrants revising an existing facility’s tier upward or down. DHS will provide appropriate notification to the facility of the reasons justifying a change in the facility’s existing tier.

Tiering is not solely dependent on the chemical of interest, but also depends on the toxicity of the chemical, the population and topography surrounding the facility, the quantity and concentration of the chemical, the pressure rating and temperature of the tanks, and the secondary containment. Although the specifics of what determines tiering is classified information, Murray said that some facilities that were previously tiered will be removed, while others that were not tiered will become tiered.

“That is primarily due to changes in plume modeling and how we are looking at the plume over the population in those areas,” she said. “Previously, we would average the population across the plume. With the new model, we look at exact data points of that population. Before, if the population was far away from the facility but within the plume, we were perhaps overestimating the risk. If the facility had a population that was directly around the plume, we were potentially underestimating the risk, because of averaging it out.”

There have also been significant changes for how facilities submit the TopScreen, making it easier to take the first step in the CFATS process. “With the old Top-Screen tool you had to go through every chemical and check ‘yes or no’,” Murray said. “Now, you can type in the appropriate chemical (such as ammonia) and immediately find it. The burden has been reduced by around 75 percent.”

Previously, facilities were also required to insert data points at each location that has ammonia. But that has also changed. “We recognize that temperature, pressure and concentration ranges can change throughout the system, so rather than require the facility to have a data point for every single option that could take place, we are allowing them to use the temperature, pressure and concentration in other aspects of the process, and wherever the final point is in the process, they are allowed to use that total quantity,” Murray said.

On its website, DHS has an instruction manual with a list of frequently asked questions specific to ammonia to guide facilities through the Top-Screen process. If a facility becomes newly tiered, Murray said, it should assess its chemical inventory, and if at 10,000 pounds or higher, to immediately begin filling out the Top-Screen, and seek the help of DHS inspectors.

“And lastly, don’t panic,” Murray said. “The vast majority of facilities are completing the Top-Screen in 10 minutes or less. It’s actually very easy.”