Safely preserving historic fire extinguishers

Jack McLaughlin, Cane River Creole National Historic Park’s structural fire protection intern, displays the two small Tetco extinguishers and large Pyrene extinguisher. All are now part of the park’s museum collection.

By Jack McLaughlin, intern, and Carrie Mardorf, National Park Ranger

Staff at Cane River Creole National Historical Park have had their fair share of fire extinguisher trainings and are used to seeing modern-day fire extinguishers throughout the park. However, when it came to antique fire extinguishers in the park’s museum collection, a level of uncertainty set in.

Container of neutralized sulfuric acid in the Pyrene® extinguisher prior to disposal.

Through a series of inventories and safety walk-throughs in early 2018, the park found a unique trio of historic fire extinguishers in the museum collection – two small red grenade type Tetco® extinguishers and one large silver Pyrene® extinguisher. Unsure about the chemical contents inside, staff contacted museum curators and regional safety experts for guidance but no one was sure that the contents could be safely emptied without damaging the historic objects.

For Jack McLaughlin, the park’s structural fire protection intern, the challenge with the three fire extinguishers presented an opportunity of a lifetime. Hired through the National Interagency Fire Center, he jumped at the chance to work with the park’s cultural resources staff to find a solution. Jack did some initial research on the extinguishers and made a scary discovery. “Like my college professor would say, the extinguishers contain a lot of methylethyl, bad stuff,” he joked. I

One of two small red grenade type Tetco® extinguishers with carbon tetrachloride in Cane River Creole NHP’s museum collection.
Large “soda-acid” Pyrene® extinguisher within Cane River Creole’s museum collection.

t turned out that the main agent in the Tetco® extinguishers was carbon tetrachloride, a substance that could smother fire but when exposed to high heat also turns into phosgene gas, which was used as poison gas during World War I.

The Pyrene® extinguisher had a “soda-based” agent that was propelled by sulfuric acid, similar to a baking soda volcano except with sulfuric acid instead of vinegar. To make sure staff encountering these extinguishers stayed safe, Jack teamed up with Gremillion E L & Son Fire Extinguishers in Alexandria to safely dispose of the contents. Park museum staff carefully packaged and padded each extinguisher for transport to Alexandria. Then working under the careful guise of Gremillion’s experts, Jack safely discharged each fire extinguisher, while preserving the original containers for the museum collection. Surprisingly the two Tetco® extinguishers still had some pressure and were discharged outside and then placed in bags to collect the remaining liquid agent.

Remaining chemical agents from the Tetco® extinguishers were collected in plastic bags prior to disposal.

The pin on the grenade-style Tetco® extinguishers turned out to be more of a pull-tab, which popped off rather easily at the right angle. The Pyrene® extinguisher was opened by unscrewing the top and the contents emptied.

The sulfuric acid, suspended in a glass container, was no longer active having been neutralized with age. “I felt like I was on an episode of Pawn Stars when they go out and test whatever it is they may buy. Talk about an amazing once-in-a-lifetime opportunity to watch these extinguishers do what they were made to do but also in a manner that we can preserve them for future generations,” Jack said after his experience and seeing other antique extinguishers Gremillion had on display. Afterward, the extinguishers were carefully rinsed with tap water to remove any remaining chemical agents and returned to the museum collection.

Jack has been employed at Cane River Creole National Historical Park since June and is working to update the park’s structural fire management plan, among many other things before his internship ends in August. He is currently finishing his degree in Fire Science Technology and balancing his career with the Marine Corps Reserve and love of firefighting.