“Employees Must Wash Hands” is a sign posted in many restaurant bathrooms. A joke was printed in New York magazine on June 12, 1989:
 
“IN THE LADIES’ ROOM OF A Greenwich Village restaurant, underneath the standard EMPLOYEES MUST WASH HANDS sign, was the graffito I WAITED AND WAITED, BUT NO EMPLOYEE CAME, SO FINALLY I WASHED THEM MYSELF.”
   
Employees, of course, wash their own hands—not the customers’ hands.
 
           
Google Books
12 June 1989, New York magazine, pg. 33, col. 4:
TRUE TALES
IN THE LADIES’ ROOM OF A Greenwich Village restaurant, underneath the standard EMPLOYEES MUST WASH HANDS sign, was the graffito I WAITED AND WAITED, BUT NO EMPLOYEE CAME, SO FINALLY I WASHED THEM MYSELF.
   
New York (NY) Times (January 29, 1992, pg. C2, col. 2)
Metropolitan Diary
By RON ALEXANDER
(...)
Dear Diary:
In the bathroom at 55 Grove Street, a cabaret, the Employees Must Wash Hands sign has been given some help. Beneath it, someone has written: SORRY, I WAITED FOR HOURS. NOBODY CAME, SO I WASHED THEM MYSELF.—ELISA DECARLO
 
Google Groups: rec.humor
SUMMARY: Request for restroom graffiti (LONG)
Mark Walsh
6/12/94
(...)     
From: “Josh Piven[Shopper]” <72241.2312@CompuServe.COM>

 
Under a sign that said “Employees Must Wash Hands,” someone scribbled “I waited and waited, but I finally washed them myself.”  Not that great, but okay.
     
Google Groups: alt.chinese.text
²ÞËùÁôÑÔ
ºÌ´ó׳
10/5/97
(...)
bathroom graffiti 17
Under a sign that said “Employees Must Wash Hands,” someone scribbled:
I waited and waited, but I finally washed them myself.
     
Google Books
W. C. Privy’s Original Bathroom Companion
By W. C. Privy
New York, NY: St. Martin’s Press
2003
Pg. 72:
On an Employees Must Wash Hands sign, some soul scribbled, “I waited and waited, but I finally gave up and washed them myself.”
 
Twitter
nikki lerebours
@XrebelrockerX
(under a sign that said all employees must wash hands) i waited and waited but then i just washed them myself
10:31 AM - 26 Apr 2009
   
Twitter
Judy Rey Wasserman
@judyrey
Under a sign that said “Employees Must Wash Hands,” someone scribbled:
  I waited and waited, but I finally washed them myself.
1:39 AM - 30 May 2009
 
Reddit—Dad Jokes
My dad was in the bathroom of a restaurant for a long time… (self.dadjokes)
submitted February 25, 2015 by wwjjgg
He came out and said: “That sign in there is wrong.”
Me: “Which one?”
Dad: “It says ‘Employees must wash hands’.”
Me: “... How is that wrong?”
Dad: “I waited for 10 minutes and an employee never came to wash my hands!”
Everyone at the table just buried their faces in their hands….
 
Reddit—Jokes
Really Funny
submitted March 25, 2015 by Kamalsworld
(...)
I was in a bathroom and I saw a sign that said employees must wash hands. I waited a minute and no one came to wash my hands so I did it myself.
 
Twitter
John
@JFD1960
I went to the toilet in McDonalds and noticed a sign that said “Employees must wash hands”. Well I waited an hour but no one came, so I washed my own”
3:45 PM - 26 Apr 2018