EMB-145 flight crew reported the Captain mistakenly activated a fire extinguisher during pre-flight activities. The aircraft was taken out of service and crew removed from the flight.
Synopsis
EMB-145 flight crew reported the Captain mistakenly activated a fire extinguisher during pre-flight activities. The aircraft was taken out of service and crew removed from the flight.
Narrative
I arrived to our flight ABCD ZZZ to ZZZZ at approximately XA:00 for our XA:58 scheduled departure. I completed the walk around and waited in the plane for about 10 minutes; before turning on the plane and beginning my setup. As I was doing my setup; the Captain texted to advise that he was running late. He sent an additional message to start boarding and that he would be at the gate in about 10 minutes. This message was sent at XA:22. Boarding had already begun and I was close to finishing all my duties when the Captain arrived. He apologized for running late and thanked me for getting the aircraft setup. At this point I had finished my setup flow; attained our clearance; programmed the FMS; and decided to use the extra time to start reviewing the company notes and approach for ZZZZ. As I was looking over the approach; I noticed a message pop up on the EICAS that said 'BAGG EXTBL INOP'. This message was not present until just that moment; and the Captain immediately said he had just inadvertently hit the button when trying to clear a message. I did not see him touch the button as I was reviewing the approach plate on my iPad while waiting for him to finish his setup. My first reaction was just that the fire extinguishing bottle in the baggage compartment wasn't going to be usable and we could run the QRH for it. But the Captain had a worried look and seemed to think he mistakenly set off the fire extinguisher in the baggage compartment by touching the guarded BAGG button. At this point; I hadn't realized that he had touched that button because I didn't see it happen. He then ran outside to check to see if the extinguisher had gone off. He was out for about a minute before coming back to confirm it had. It wasn't until this point that I realized he had pressed the BAGG button and that was why we were getting the EICAS caution message for it being INOP. He proceeded to call Maintenance who came a few minutes later. We were then advised to deplane and that we would be switching aircrafts. Within 15 minutes; he was called that he would be removed from the flight to take an alcohol and drug test. Then about 15 minutes after that; I called Dispatch and scheduling to get an update on our flight and was advised by them that I was also going to be removed from the flight in order to do an alcohol and drug test.
Second reporter narrative
During the boarding process I noticed the bag extinguisher light illuminated. Nothing on the EICAS indicated a fire and I went outside and saw the cargo was being loaded with no sign of a fire. Passengers in the cabin were not complaining of smoke in the rear. I took my seat and attempted to reset the light by doing the fire test. However; I did not look up and attempted to feel for the button and mistakenly pressed the BAGG extinguisher button. As soon as I realized what I had done I when outside to see if anyone was in the cargo bin and noticed the rampers were already outside. One was on the belt loader and the other came up to me to say he saw some smoke release from inside the cargo bin. I told him it was the extinguisher and I was going to contact Maintenance. He said OK and was in the process of uploading the green tag bags and I instructed him not to load anything until Maintenance got there. I called Maintenance and made a logbook entry.I should have slowed down after assessing there was no threat and called Maintenance to talk me thru the process. We are trained not to immediately press the button but confirm if a fire exists or not. I did those steps but used muscle memory to try clear the fault. Perhaps instead of doing the fire test perhaps we should emphasize just call Maintenance to clear the light after verifying there is no fire threat.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.