which episode of the office is the fire drill
The fourteenth and fifteenth episodes of the fifth season named "Stress Relief".
Stress Relief (The Office)
"Stress Relief" is a two-part episode of the American comedy television series "The Office". They constituted the fourteenth and fifteenth episodes of the fifth season, and the 86th and 87th overall episodes of the series. Both episodes were directed by Jeffrey Blitz and written by Paul Lieberstein, who also plays Toby Flenderson on the show.

In this episode, Dwight stages a fire in the office to test the office's fire safety skills, but things go from bad to worse when Stanley suffers a heart attack, causing Michael to come up with ways to relieve stress in the office, including a comedic roast of himself.
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Stress Relief (The Office) [SEP] Introduction
"Stress Relief" is a two-part episode of the American comedy television series "The Office". They constituted the fourteenth and fifteenth episodes of the fifth season, and the 86th and 87th overall episodes of the series. Both episodes were directed by Jeffrey Blitz and written by Paul Lieberstein, who also plays Toby Flenderson on the show. In this episode, Dwight stages a fire in the office to test the office's fire safety skills, but things go from bad to worse when Stanley suffers a heart attack, causing Michael to come up with ways to relieve stress in the office, including a comedic roast of himself.