Similar to a chinese fire drill. However, instead of waiting to get to a stoplight, participants exit the car while it is still moving. Can be performed with multiple cars and also with multiple cars where only the drivers switch. This manuever is usually preceded by several pints of guinness.
Alex: ......a chinese fire drill? Does it involve fireworks?
Ben: I said irish fire drill you retard. Its a cocktail with 2 parts beer and three parts stupidity.
The Irish fire drill is an alternate performance of the Chinese fire drill, in which one member of the traveling party exits the vehicle (while stopped at a light or in traffic), urinates, and then returns to the vehicle.
Connor: Come on guys, I really have to pee.
Sully: We're already late, just perform an Irish fire drill.
Connor: *leaves car, urinates on road shoulder, returns to car*
Pulling a fire alarm in a crowded bar for no apparent reason.
When we were hanging out at O'Brian's the other night and Ryan McMurphy was just standing there, quietly drinking his Guinness, I should have known he was about to pull an Irish Fire Drill.