On Monday February 22, the Central Maryland region experienced snow and sleet which made road conditions hazardous for travel. At 1050 hours (10:50 am), the Mount Airy VFC was dispatched for a vehicle collision on Route 27 in the area of Interstate 70 with reports of a truck overturned underneath the interstate bridge. While responding, reports were relayed to units of possible hazardous materials involvement.

Rescue 1 and Medic 18 arrived to find a large stake body truck carrying shipments of compressed gas cylinders that had overturned on northbound Route 27 directly underneath the Interstate 70 overpass bridge. There were numerous cylinders in the roadway leaking their product and units were unsure of the exact hazards. A hot zone was set-up that closed Route 27 north and south of the incident and a request was made to shut down Interstate 70 in both directions due to the potential hazards from flammable and non-flammable gases leaking. Chief 1 established the Route 27 command and requested the Hazardous Materials response to assist. Crews were able to deploy a handline for protection and quickly evaluate the lone driver and determined there were no injuries and worked on gathering information on the hazards of the products being transported.

The Carroll County Hazardous Materials team arrived on the scene and began an evaluation of the hazards. It was determined that the products involved creating the biggest hazards were two large liquid oxygen cylinders, several small acetylene cylinders and a single methane cylinder. Crews also observed a large amount of vapors from shipments of liquid nitrogen that was leaking and dry-ice bins that had dispersed onto the roadway. A reconnaissance was performed utilizing a Hazmat Tech and firefighters from MAVFC to determine any hazardous atmosphere and perform a damage assessment of the truck and cylinders involved. It was determined that there was active liquid oxygen and nitrogen leaks and the status of the flammable gas cylinders was still unknown. A diesel fuel leak was also observed that would need mitigation to ensure it did not come in contact with the liquid oxygen.

Additional Hazardous Materials Team assistance was requested from Frederick County and Maryland Department of the Environment while crews stood by and ensured a safe area. Once all personnel and the responsible party arrived on-scene, a plan was established to mitigate the hazards from the leaking cylinders. A hazardous materials crew made entry with back-up support from MAVFC personnel. The crews were able to safely upright the leaking cylinders and use air monitoring devices to ensure there was not a hazardous atmosphere. Once the hazards were mitigated, the scene was turned over to Maryland State Police and Maryland Department of the Environment to work with the responsible party for clean-up. Interstate 70 was re-opened approximately one hour after being shut down and Route 27 opened southbound. Once the vehicle was up righted and the scene cleaned-up, Route 27 was completely reopened and traffic was allowed through again.

The incident was handled safely and efficiently with no injuries to civilians or firefighters. The Mount Airy statin was covered by Winfield E142 and Frederick County A38.