• Change in colour
• pH drop
• Strong unpleasant odour – bad eggs / Fustiness
• Ammonia bloom
• Emulsion instability
• Corrosion

Unpleasant smell / acidic

• Coolant dripping from overhead equipment, air extractors etc.
• Irritation of nose and throat

• Change in colour (yellowing)
• Free oil on the coolant surface
• Higher turn-over rates
• Invert emulsion
• Soaps
• Dirty machine / sticky deposits
• Emulsion phasing

High foam levels

• Smoking during cutting operation
• Irritation of nose and throat

• Deposits on machines, systems tanks and flumes
• Musty odour
• Low coolant flow / supply

• Geometric tolerances & / or surface finish
• Burning of tool / increased tool wear

Red / Sores / Itchy / Dry skin

Discolouration of machine surfaces or components