Also, when freeing stoppers from flasks or bottles, take extra care, especially if the contents are hazardous. Eye protection is mandatory when operating glass apparatus under vacuum. The use of plastic mesh covers is not recommended. Evacuated glass dessicators should be protected with a metal mesh cage and should not be transported when evacuated. Air should be admitted gradually when a vacuum within a glass apparatus is to be released.
Great care is required when handling large pieces of glassware with wet hands.
Strong acids, strong alkalis, toxic, and radioactive solutions must never be pipetted by mouth. An approved pipette filler design should always be used. Fitting pipette pumps or other pipetting aids incorrectly often leads to serious glass cut injury. Pipetting aids should be fitted with great care, utilizing suitable lubrication where necessary, and employing a protective cloth, in case the pipette should fracture. Laboratory workers should receive instruction in the correct use of mechanical pipetting devices.