“Ed!” Edna stood in the bathroom, brow furrowed.

“Yes, honey?” Ed shuffled down the hall from his den.

“Something’s wrong with the toilet. I keep flushing it, but the water isn’t clear. I think we need to call the plumber.”  Edna pressed the flush lever and frowned.  “Or … you didn’t … improve this did you?” 

“Don’t worry!” Ed proudly lifted the toilet tank cover. “The toilet isn’t broken.”  Edna could see that the tank water was also murky.  “I made a few changes to the plumbing to recirculate the water. This is how we conserve water with the tabletop sterilizers in the lab.”

“What?” Edna pulled back, her eyes wide with disbelief. Ed replaced the tank cover.

“Oh yeah, it’s the latest and greatest in water conservation—waste water recirculation!”  Ed looked down at the murky toilet bowl for a moment. “But we should probably keep the lid closed from now on.”

Common sense will tell you that conserving water in every situation is not safe, let alone a good idea. Recirculating water works for light-load dental-style tabletop autoclaves, which are primarily used for rendering clean medical instruments and dental tools sterile for immediate use.  But tabletop autoclaves installed in research facilities should never recirculate water: there’s risk of contamination (creating a perfect breeding ground for Legionella, among other pathogens) and a near certainty of ultimately damaging the unit, drastically decreasing its working lifespan.  The practice is not allowed in the European Union at all, and one that Priorclave does not use in any tabletop sterilizer.