“Exit signs are on the way out” is a jocular one-line saying that has been printed on several images. “Are exit signs on the way out?” was posted on newsgroup alt.drunken.bastards on August 22, 1996.
         
“Exit signs—they’re on the way out” has been credited to English comedian Tim Vine since at least 2002.
 
     
Google Groups: alt.drunken.bastards
Hey Mr Tramp! Ya feet still smelly?
Jaz
8/22/96
(...)
Jaz - Are exit signs on the way out?
 
Google Groups: bit.listserv.bgrass-l
Grave Omission
John Moone
3/27/98
(...)
I think EXIT signs are on the way out
 
Google Groups: bit.listserv.bgrass-l
more on the old house
dibowde
3/28/98
(...)
I, too, think that exit signs are on the way out.
 
Google Groups: alt.comedy.british
alternative comedy
Ian F.
4/15/02
Dan Owen wrote:
> Ah, yes. Tim Vine
(...)
“Exit signs - they’re on the way out.”
 
27 June 2004, The Sunday Mail (Brisbane, Queensland), “Exit signs on the way out” by Daniel Knowles, pg. 30:
“EXIT” signs are on the way out under changes proposed by regulatory watchdog Standards Australia.
 
The regulator wants traditional emergency signs, green and white with “EXIT” written on them, to be gradually replaced with a sign of a green man moving through a door.
 
Google Groups: sci.engr.safety
exit signs
.(JavaScript must be enabled to view this email address)
4/18/05
Exit signs are on the way out.
     
26 October 2006 Evening Standard (London, UK), “Vine is a marathon punner; Comedy: Tim Vine Aylesbury Civic Centre” by Bruce Dessau, pg. 30:
Like a comedy excavator he unearths hidden meanings in daily language: “Exit signs. They’re on the way out.” It helps that Vine looks funny, mixing Jacques Tati’s angularity with Tommy Cooper’s amiable shuffling.
 
Twitter
Hearn
‏@hearn
Exit signs. They’re on the way out, aren’t they?
8:20 AM - 15 May 2008
 
Twitter
Jonathan Phillips
‏@DigitalJonathan
@pete_gilbert Exit signs: They’re on the way out…
4:05 PM - 18 Feb 2009
 
Google Books
The Invisible Church:
Learning from the Experiences of Churchless Christians
By Steve Aisthorpe
Edinburgh: Saint Andrew Press
2016
Pg. 64:
Mapping exit routes
In a typical one-liner, my favourite comedian, Tim Vine, declares: ‘Exit signs [pause] – they’re on the way out’.