Kelly Pyzik, Editor in Chief
pyzikkel@grinnell.edu
The Grinnell Fire Department responded to an ammonia refrigerant leak at PurFoods this Monday, Oct. 5, at 4:52 p.m. Thirty workers were evacuated from the building, eleven of whom experienced breathing difficulties and were transported in ambulances to Grinnell Regional Medical Center. They were all treated and released by the end of the night and the building was cleared of the ammonia by 8 p.m.
According to Grinnell Fire Department Fire Chief Dan Sicard, PurFoods employees at the 810 Blakely Circle building had started to smell an odor, and when a maintenance worker went to investigate, he could hear the refrigerant leak from outside the warehouse area. The building supervisor was already evacuating workers when the fire department arrived on the scene.
“The amount in the occupied area of the building was relatively low for a leak. The amount in the area [of the leak] was well over what we would call the IDLH – Immediately Dangerous to Life and Health. It was well over that amount and required a hazmat entry to shut down the leak,” Sicard said. “We were able to monitor and do readings in the building to make sure the material was completely out of the building. We have some positive pressure pans we used to move a lot of fresh air into the building and move the bad air out.”
PurFoods is an Iowa-based company that delivers pre-packaged meals to the homes of senior citizens and other people who may have difficulty cooking for themselves. At this PurFoods building, there is a large refrigeration warehouse where ammonia is used as a refrigerant. When not properly contained, as with a leak, ammonia in gas form is toxic by inhalation and corrosive by contact as a liquid. According to Sicard, ammonia inhalation at low levels irritates the eyes, nose, throat and respiratory systems. It can cause burning sensations and breathing difficulties. In higher doses or with longer exposure, it can lead to respiratory failure.
There are safety precautions that must be taken when using ammonia for industrial purposes. While PurFoods took many of the expected safety precautions, they have an older refrigeration system that does not have certain safety shutoff features present in new systems, which are now legally required when new systems are purchased and installed.
“If you’re using it in a [refrigeration] system like [theirs], some of the safety precautions are that you have emergency ventilation areas and a pre-plan with the local first responders so that they know it’s there, which we had done with this company,” Sicard said. “The system they have is an older system so it doesn’t have some of the emergency shutoffs that are now required by law.”
PurFoods could not be reached for comment.
Anthony • Nov 3, 2015 at 5:10 pm
Thanks for the update Kelly!
“There are safety precautions that must be taken when using ammonia for industrial purposes.” is exactly right.
The basics of Ammonia must be understood when working with refrigeration. Ammonia is ideal for refrigeration because of how thermodynamically efficient it is over other refrigerants, but it can also be very dangerous because there’s usually a large amount present when working with industrial refrigeration. You can read more about it here: https://www.graphicproducts.com/articles/basics-of-ammonia-refrigeration/