Waste Anesthetic Gas (WAG) Guidance

Waste anesthetic gases such as Isoflurane or Halothane are considered suspect reproductive toxins. Be sure engineering controls such as a chemical fume hood or an appropriate anesthetic gas scavenging system are used to control exposure. DEHS has a halogen leak detector and can also collect personal air samples to determine exposure levels. Contact the DEHS Lab Safety Coordinator , or 852-2830, to periodically assess your system.

Implement the following precautions to reduce your exposure:

  • Equipment Leaks – Before use, check the connections and proper operation of the anesthesia machine and scavenging system.

  • Filling Vaporizer Reservoir – Use an anti-spill filler funnel to pour liquid anesthetic into vaporizer. These are available from vaporizer suppliers.

  • Turning Vaporizer On and Off – Avoid turning the vaporizer on until the circuit is connected to the animal and turn off when not in use.

  • Nosecone – Select nosecone that is appropriate for the face contour of the animal. Don’t administer the anesthesia until you’re sure the nosecone forms a good seal.

  • Induction Chamber – Make sure there are tight seals for each opening of the induction chamber. Turn vaporizer off and let oxygen flush out the chamber before removing the animal.

  • Disconnecting – Stop the flow of anesthetics before disconnecting the circuit.

  • Nosecone Removal – Before nosecone removal or extubation, flush the circuit with oxygen.

Department of Environmental Health And Safety

Main Office

1800 Arthur Street

Louisville, Kentucky 40208


tel (502) 852-6670

fax (502) 852-0880

Department of Environmental Health And Safety

Radiation Safety Office

319 Abraham Flexner Way

Louisville, Kentucky 40202


tel (502) 852-5231

fax (502) 852-8911

Office Hours

M-F 8:00 am to 4:30 pm

No holiday hours

IH Service Account


IBC Service Account