[Quality Control of Medical Instruments and Cleaning Water]

Herein we aimed to investigate the degradation of surgical instruments in our hospital and how water quality affects the rate of metal corrosion.

We observed 279 stainless steel instruments, and determined the presence of damage like metal corrosion or scale formation. We also measured the concentrations of chloride(Cl^-)and silicate(SiO₄^4-)ions in the water used for cleaning in our operating rooms, including tap water from the city water supply and reverse-osmosis(RO)filtered water.

Pitting corrosion was observed on 71% of the instruments we investigated. The concentration of Cl^- was 0.7mg/L in tap water and 0.1mg/L in RO water, while the concentration of SiO₄^4- was 0.3mg/L in both the tap and RO water.

Of the dissolved ions Cl^- and SiO₄^4-, Cl^- is more of a concern, as it causes pitting corrosion over time, while SiO₄^4- causes scale formation. Considering the typical water quality in the operating-room environment, degradation must be monitored for the general maintenance of metal surgical instruments.