A variety of stains or spotting might appear on your instruments after the cleaning and autoclaving processes have been completed. Most likely, these are not rust, but rather an indication of improper cleaning or sterilizing procedures.

 

The following chart can help you identify and prevent or remove many of stains that typically show up on nippers.

 

Stain/Spot Colour

Possible Causes

Solutions

Brown/Orange

Bio-burden (tissue, blood, etc.) left on instrument

Use an eraser/buffer to rub off the stain

Detergent pH is too high (>8)

Choose a cleaning solution with a neutral pH
Soap/detergent residue on drapes/ towels used in wrapping Review laundry protocol to improve soap-free rinse

Rust

 Mixing instruments made of different metals in the same cleaning or  sterilizing cycle

Separate instruments by metal type for cleaning and sterilization

Tap water has high mineral content

 Use distilled water and thoroughly dry instruments after rinsing
Black/Brown with Pitting

 

Cold soaking of instruments

 Eliminate cold soaking and potential exposure to chemicals during that process

Detergent pH is too low (<6)

Choose a cleaning solution with a neutral pH

Blue/Black

 Mixing instruments made of different metals in the same cleaning or sterilizing cycle Separate instruments by metal type for cleaning and sterilization

Blue/Gray

Improper cold sterilization

Check solution instructions and follow recommended temperature and soak times

Chemical or mineral residue

Use distilled water and thoroughly dry instruments after rinsing

Spotting

Slow or improper drying of instruments

Review autoclave manufacturer’s instructions

Mineral residue

 Use distilled water and thoroughly dry instruments after rinsing

Multi / Rainbow Colour

Excessive heat during sterilizing cycle

Review autoclave instructions