"I think I'm going to go and have a cold beer," he told reporters shortly after he and 19 of his colleagues were brought safely back to the surface.
The blaze broke out at about 2 a.m. Tuesday when a large wooden cable spool started burning at PotashCorp.'s Rocanville mine, about 244 kilometres east of Regina.
There was no panic, said the miners, who immediately headed to four separate refuge stations scattered throughout the facility.
"We have an alarm system with loud bells and flashing red lights, and you immediately go to a refuge station and call the control room so they know where you are," said Wirth.
It took about 10 hours to extinguish the fire, but it took several more hours for crews to determine it was safe to bring the workers up.
"It's a matter of cooling the area down and ventilating the air," said Bill Cooper, spokesman for PotashCorp.
"There's kilometres of tunnels underground and just the way the ventilation system works, it's got to clear all that out. The air quality's got to be at a point where it's safe to take people to the surface."
So the miners sat and waited at the refuge stations — large rooms that are sealed off from the rest of the mine and have air, water and canned food for several days.
The rooms are comfortable, though not really posh.
"There's no place to sleep," said Wirth, who laughed when told another group had passed the time by playing cards.
"We didn't have a deck of cards. We really would have liked a deck of cards."
Originally, 29 men were trapped but nine of them were brought up earlier in the day.
There are four mine rescue teams at Rocanville, each with five people. Cooper said they take turns trying to put out a fire.
"As you can imagine with a mine fire, there are a few more challenges than, let's say, a house fire. So it's a bit of a slower process and a more deliberate process," said Cooper.
The Rocanville potash mine is about one kilometre below ground, but tunnels from the main shaft spread out horizontally for about 16 kilometres.
"Our task was once we find out that there is an emergency, the protocol is to get ahold of all our guys," explained mine rescue supervisor Courtney Ryan of Tantallon, Sask.
"We also talk to Mosaic Potash and if we need any of their help, they support us."
He said the fire is not what poses the greatest threat.
"Smoke is the worst thing that can happen underground. If you don't have your fresh air and exhaust separated, smoke goes where it's not supposed to go and people can become engulfed by smoke.
"We had enough ventilation so that the smoke didn't back up too far so we were able to approach the fire within 20 to 50 feet. It was nice to get it done and the guys home."
It is not the first time a fire has broken out at a Saskatchewan potash mine.
In January 2006, 72 miners survived a fire at Mosaic's potash mine in Esterhazy.
When heat from a cutting torch ignited a fire in some plastic piping on Jan. 29, the 72 miners on shift were able to retreat to refuge rooms sealed off from the toxic smoke. It took 30 hours, but all of the miners were brought to the surface without so much as a cough, according to company officials.
Esterhazy has been heralded as a textbook example of mine rescue.
Cooper said PotashCorp.'s emergency action plan worked well.
"Thankfully all of our employees are safe and healthy," he said.
— By Jennifer Graham in Regina