Vanessa Aguayo and Antoya Ellis ordinarily address the hottest of the hot button issues that besiege industrial fire protection using cold equations and sophisticated computer models. Chevron’s corporate fire school in May marked their first time wearing bunker gear and breathing apparatus.
“I want to understand what firefighters actually go through, what they feel,” Aguayo said. “In that way we can design better fire protection systems for them.”
Aguayo and Ellis, 11 and six-year Chevron employees, respectively, are Fire Protection Engineers working in Chevron’s Energy Technology Company in Houston. They design fire protection systems including completing and verifying hydraulic calculations and transient analysis, fire and gas detector placement and conduct 3D mapping analysis. Their work protects the company’s refineries and upstream assets worldwide.
One project that Aguayo and Ellis have under their belt is developing specifications to implement full-surface and rim seal fire suppression for large-diameter flammable liquid storage tanks.
If sensors on the tank detect flames, a signal activates a pressurized foam system. This fixed foam system floods a ring around the tank rim. An even coat of foam pours down the interior wall of the tank, pushing across the flammable product to meet and smother the flames.
Chevron has already adapted this system to tanks more than 200 feet in diameter around the world.
Aguayo, who holds a degree in chemical engineering from the Colorado School of Mines, and Ellis, a Tuskegee University graduate with a degree in mechanical engineering, ensure the correct foam and application rates are implemented for this system to achieve extinguishment, taking variables such as tank diameter and type of foam into consideration.
“We need to ensure that the system is discharging the correct amount of foam to suppress the tank fire,” Aguayo said.
Since actual testing in storage tanks that large would be costly and dangerous, Aguayo and Ellis are currently working with the fire industry and foam manufacturers to understand the correct application rates for newly developed foam.
Understanding the correct type of foam and application rates is only one piece of the equation. “We use modeling programs to understand the hydraulics and ensure each system is designed correctly,” Aguayo said.
Aguayo and Ellis are also working with a team of industry fire experts to investigate and evaluate the effectiveness of different foams on various fuel sources. The intent is to provide information and recommendations for adoption into the 2021 edition of NFPA 11, the standard covering the design, installation, operation, testing and maintenance of low-, medium-, and high-expansion foam systems.
“We need to understand what application rates will successfully extinguish fires,” Aguayo said. “We’re working with the fire industry’s top experts from different oil and gas companies, foam manufacturers and consultants to understand what this means.”
Not all the work for this project is done at a computer keyboard, Ellis said. At lot of field work is involved.
“We are visiting plants to test the current foam concentrate,” Ellis said. “The test results will give us a baseline as to where we stand. Then we will make sure that the new foam incorporated as per NFPA 11 is adequate to fight fires.”
The goal is to provide the firefighters adequate information about any new foam to avoid unpleasant surprises, she said.
“Our team wants to ensure that we’re not going to have a major change,” Ellis said. “We do not want the firefighters going through a big adjustment with this new foam being implemented.”
A chief concern is any increased time necessary to achieve extinguishment, she said.
“We do not want firefighters out there any longer than they need to be,” Ellis said. “ From observing the Firefighting school, we now understand how hot bunker gear can get. So, we do not want to implement something new where they have to endure that condition any longer than they have to.”
Observing live-fire training at close range in full bunker gear and SCBA gave her a greater appreciation of what firefighters’ endure in the line of duty, she said.
“I prefer my day job,” Ellis said. “I respect the folks that are out there but direct firefighting is not my calling.”