Pesticide warning signs: greenhouse door handle

Greenhouse worker making adjustments to sign reading, "Danger, Keep Out"
Photos by Kit Galvin
Photos by Kit Galvin
Post the warning sign over the door handle. No one can miss it, as they will need to reach under the sign to find the door knob.

idea iconIdea...

A pesticide handler was preparing to apply pesticides in a greenhouse room. He posted the large warning sign on the door. Then an employee entered and claimed that he did not see the sign. Since the signs have covered the door handle, no one has entered a posted restricted area.


alert iconAlert

Remember to remove the warning sign each time after the REI ends. People may start to ignore signs, if they are left up after the REI.




"We have been using them since the early 2000s. We recommend it to other people in the industry. There shouldn’t be an excuse for not seeing the sign".
Greenhouse manager


setup iconSetup & use

  • Use the full size (14" width  x 16" height) warning sign.
  • Cut a slot in the warning sign just big enough to slip over the fixed staple.
  • Install the fixed staple to the door.
  • Slip the sign over the staple and insert the linchpin.


supplies iconSupplies

  • Warning sign (16" H x 14" W), stiff and waterproof
  • Linchpin
  • Fixed staple with screws



Warning sign assembly.



Close up view of sign reading, "Danger, Keep Out"



tips iconTips

  • Center the slot horizontally.
  • Place the staple and linchpin where they don’t obscure the words or images.
  • Store the linchpin in the staple to be ready for next time.
  • Use a lock in place of a linchpin for outside doors.


PERC Worker Protection Standard Guide

Pesticide Educational Resources Collaborative (PERC

Worker Protection Standard 


Washington State (Washington Administrative Code)

Oregon State (Oregon Administrative Rules)

  • OARs 437-004-6000, 170.1 - 170.260 Subdivision W, Worker Protection Standard
  • OAR 170.405 Entry restrictions associated with pesticide application

  • OAR 170.407  Worker entry restrictions after pesticide applications

  • OAR 170.409 Oral and posted notification of worker entry restrictions



Last updated

We hope that you are inspired to use these solutions in your workplace. Did you try one of the practical solutions or develop a new one? We would appreciate hearing about your ideas and experiences.

Thank you and safe pesticide handling,

Contact your state agency for more information on WPS regulations. The content of this website is for informational purposes only. It may need modification to fit your needs or it may not be appropriate for your workplace. Safe use of these solutions is your responsibility. The University of Washington and the Pacific Northwest Agricultural Safety & Health Center is not responsible for any loss or damage resulting from the use of the information provided on this website.

PNASH Project 2016-2021 (CDC/NIOSH Cooperative Agreement # U54 OH007544)

Contact us

Project Email:

Project staff:
Kit Galvin
Maria Tchong-French (habla español)
206 685-6728