When it reaches the pressure of the rest of the ship, you can take your space suit off.
7 seconds sound clip from the Santa Claus Conquers the Martians (1964) movie soundboard.
You can hear this line at 00:46:48 in the Blu-ray version of the movie.
Quote context
[...]
- Now, now, Billy boy. That's not the Christmas spirit.
- Why, of course. We'd love to take the grand tour. All right, children.
- Airlock.
- Sure. This is where you come when you're ready to go out in space. It's airtight.
- When it reaches the pressure of the rest of the ship, you can take your space suit off.
- Well, where's the control that opens the door?
- Not here. That's in the control deck.
- You see, once you pull that switch, the warning bell sounds, and in 60 seconds, that door opens.
- That's to give the spaceman a chance to make a final check on their equipment.
[...]