Originally, the primary considerations for establishing building siting locations were made on the basis of purely pragmatic information, such as spacing tables and charts that would prescribe separation distances from process equipment.
However, this approach overlooks the most important and valuable resource on the site: the people.
Like many technological processes, the history of facility siting is fraught with accidents, injuries and fatalities. At a recent panel discussing facility siting concerns during AFPM's 2021 National Occupational & Process Safety Conference, Morgan Walker, process safety director for Phillips 66's San Francisco Refinery, recalled one such incident: the refinery explosion in Texas City, Texas, in 2005. Since then, he said, industry has steadily increased its quantity and quality of programs centered around the prevention and management of potential effects that over-pressure, toxics and fire have on workers in process areas. Industry has made tremendous strides at improving the safety of workers, he said, but there are still a number of gaps and traps that may be overlooked in facility siting decision making.
"You need to be considering the siting in terms of 'protection concepts,'" said Christine Carlson, loss control engineer for Koch Companies Services. When assessing an occupied building in a process area, she said, you need to ask yourself whether the building can be considered for shelter-in-place, safe haven or evacuation. That classification should be determined first, as it will steer all of the other siting decisions that follow.
"Every building has a design basis, and that design basis needs to not only be a determining factor in the siting, but it must also be shared with the building's occupants and emergency response," she explained.
If a building is rated as shelter-in-place or safe haven, the ability of the building to support occupants and how long it can maintain that support have to be determined and communicated before and during any event. The communication component is often overlooked, which is why appropriate signage is necessary, she said.
To illustrate the necessity of signage, Carlson offered an example scenario. "If there is a release of toxics, building occupants will need to know whether the HVAC will automatically shut off or if it needs to be shut off manually," she said. "If the occupants don't automatically know the answers to life-saving questions like that, then how will they know what they need to do without signage?"
Another key consideration is the building's two-way communication capabilities. "For some blast-resistant modules (BRMs), which are metal buildings, it can be hard to get radio or cellphone reception inside," Carlson said. "If you have issues with cellphone or radio coverage inside a BRM, how are you going to communicate with the occupants and emergency responders during an incident? Is the building equipped with a repeater or an antenna? You not only have to know those answers, but you have to rigorously test them before an incident can occur, as well."
Work together with other programs
According to Irina Kopponen, senior process safety consultant for Phillips 66, shutdowns and turnarounds require their own unique facility siting considerations.
"During shutdowns and turnarounds, it's so important to perform a special assessment of the buildings," she said.
Shutdowns and turnarounds usually entail the on-site presence of contractors and consultants who are unfamiliar with or unaware of not only the holistic perspective on the site's safety, but also with the protection concepts for the individual buildings where they're working.
That's why, Kopponen said, facility siting needs to partner and work with other departments and programs. "In your assessments, facilities need to work together with emergency response and even environmental to make sure all the bases are covered, both for your regular personnel and any external workers on-site to assist with the shutdown or turnaround," she explained.
