The removal of solutions from vials most commonly takes place inside industrial washing machines in labs and schools. These washing machines heat the vials in water at 120 degrees F or higher to sterilize them. The movement of water in and out of the vials breaks up remnants of solutions and washes them away. For vials used in particularly chemical-heavy experiments, the washing machine may be hotter and/or the vials washed for longer to make sure all traces of solution or chemicals are wiped out. If an industrial-strength washing machine is not available, vials may be soaked in hot water for three hours.
Scrubbing tools specifically designed to cleanse vials are sold in lab-equipment stores and catalogs. Long-bristled scrubbers fit tightly in standard vials and break up dried collections of powdered solutions. Placing the scrubber into a vial and twisting it around will comb out any remains of solution that normal washing does not. It is recommended to re-wash any vial that has just been scrubbed because loose, dried bits of solution may remain in the vial. Keeping the scrubber clean is essential as well, and most scrub tools can be washed in the same machines as the vials.
After washing and scrubbing, dry sterilization is the next step. Vials can be dried in devices specifically made for that purpose or on sterile drying racks. After the drying process, which generally takes an hour, inspection will show if solution still exists anywhere on the vial. If any solution is still present, washing and scrubbing should be repeated.