‘Countdown’ bosses evacuated the studio after Susie Dent complained of strong gas fumes.
The 55-year-old lexicographer – who has appeared in Dictionary Corner on the show since 1992 – first noticed the scent as cameras filmed the opening episode of the day alongside guest Janet Street Porter, and the 72-year-old journalist raised the alarm as managers soon ordered everyone off the set of the Channel 4 programme at MediaCity in Salford, Greater Manchester.
One audience member told The Sun newspaper: "There was genuine panic at first and everyone was wondering what Susie and Janet were in a huddle talking about.
"It was half way through recording of the first episode and as we left others said they could smell gas as well.
"One by one more people got involved and we were finally told we had to leave the studio. It was a bit alarming to say the least."
However, after a 30 minute wait, technicians ruled out any signs of a dangerous gas leak, and filming resumed for the early week episodes..
‘Countdown’ host Nick Hewer, 75, was the last to return to the set to get the show up and running again.
Meanwhile, word whizz Susie has previously admitted she has received lots of "strange" fan letters but bosses "filter out" the oddest messages and gifts.
Susie – who stars on the popular show alongside Rachel Riley – said: "Our wonderful ‘Countdown’ team tend to filter out strange messages or presents that come our way.
"But ‘Countdown’ viewers are second to none in their loveliness. I remember the office being inundated with Gypsy Cream biscuits after Richard Whiteley mentioned he loved them.
"Rachel Riley has had so many beautiful baby gifts she’s overwhelmed! And I did once receive a marriage proposal from a member of the audience, but I am not sure it was entirely serious!"