Ammonia Blast at Vegetable Packing Plant Injures 12

Dec. 03--Two people who were exposed to an anhydrous ammonia explosion are currently being treated in a Phoenix hospital. They were severely injured while working at a vegetable packing shed Friday afternoon.

According to the Yuma Fire Department, the incident occurred at about 3:50 p.m. at Yuma Express Cooling, 4139 E Gila Ridge Road.

Joel Faz, who was driving in the area, witnessed the explosion unfold.

"There was a semitruck in front of me and a car right in front of me," he said. "The semi- truck made a turn, and as we started to go again, there was a huge explosion."

According to Faz, who had his window open, there was a boom so deafening "it hurt my left ear. I was right there in the street right at the intersection where it happened."

Faz saw two men try to escape the explosion.

"They were in between two tanks," he said. "Right when it happened, one guy came running out first, and he was about ten feet in front of the shock wave. The guy behind him was engulfed in that."

The shock wave "literally picked him up," Faz said. "It looked like he was off the ground about two or three feet for about five or six feet, until he finally hit the ground running again. It was an unbelievable sight. It just blew me away."

The plume of ammonia smoke was about 45 feet high, Faz noted, adding that people who were evacuating a nearby building ran right into it when they exited.

"The alarms started going off immediately, and they were going out all the exits, and they didn't know what they were getting into. The wind carried it toward the southeast where everybody was evacuating. They were running into the plume of ammonia. Once they got in the cloud, they still had to try and get away."

The first YFD units to arrive on scene found multiple victims with varied degrees of ammonia exposure. The most severe exposure victim was transported immediately to Yuma Regional Medical Center by a YFD Rescue truck.

Exposure to anhydrous ammonia is extremely dangerous, and large doses can be fatal.

According to the Agency for Toxic Substances and Disease Registry, ammonia is highly irritating to the eyes and respiratory tract, and can cause swelling and narrowing of the throat and bronchi, coughing, and an accumulation of fluid in the lungs.

Prolonged skin contact can cause pain and corrosive injury. Exposure to concentrated vapor or solution can cause pain, inflammation, blisters, necrosis and deep penetrating burns, especially on moist skin areas. Skin contact with compressed, liquid ammonia, which is stored at –28ºF, causes frostbite injury and may also result in severe burns with deep ulcerations.

After the first victim was transported to YRMC, YFD personnel, working in cooperation with Rural Metro ambulance personnel, evaluated patients and readied them for transport. Eleven additional patients were transported to YRMC. Two, including the first victim transported by YFD, were flown out to medical facilities in Phoenix.

Three YFD and seven Rural Metro personnel were also decontaminated and evaluated for exposure to ammonia.

Yuma Police Department personnel blocked off traffic on Gila Ridge Road between Avenue 3E and Araby Road during the incident to facilitate access and movement of emergency vehicles. Traffic remained blocked for approximately two hours. The street was reopened at about 6 p.m.

As emergency medical operations were underway, YFD hazardous materials technicians and Yuma Express Cooling employees confirmed the leak had been stopped and took additional actions to stabilize the situation.

The leak was believed to have been caused by a failure of a connection to a condensing coil on a cooling tower, YFD said.

The incident is under investigation.

Chris McDaniel can be reached at cmcdaniel@yumasun.com or 539-6849.

Copyright 2011 - The Sun, Yuma, Ariz.