c556c467_egal__Cleaning___Sterilization_Pre_Anesthesia_Checklist_2008_Rationale
[Step] Verify that vaporizers are adequately filled and, if applicable, that the filler ports are tightly closed. [Rationale] 
If anesthetic vapor delivery is planned, an adequate supply is essential to reduce the risk of light anesthesia or recall. This is especially true if an anesthetic agent monitor with a low agent alarm is not being used. Partially open filler ports are a common cause of leaks that may not be detected if the vaporizer control dial is not open when a leak test is performed. This leak source can be minimized by tightly closing filler ports. Newer vaporizer designs have filling systems that automatically close the filler port when filling is completed. High and low anesthetic agent alarms are useful to help prevent over- or under-dosage of anesthetic vapor. Use of these alarms is encouraged and they should be set to the appropriate limits and enabled.
Anesthesia Gas Machine- Machine checklist, Medicolegal, Cleaning & Sterilization
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