Cited as the second most common Occupational Safety and Health Administration (OSHA) violation in fiscal year 2021, respiratory safety continues to be a challenge in the workplace. Metalworking is no exception.
Although supplying workers with respirators to protect them from airborne hazards is one way to prevent exposure, there is often an underlying culprit in metal fabrication that should be addressed: poor cutting fluid maintenance.
As cutting fluids deteriorate, mist or aerosol creates several respiratory health problems including acute airway irritation, asthma, chronic bronchitis, chronically impaired lung function, and hypersensitivity pneumonitis. Dermatological issues including contact dermatitis and acne also emerge.
According to OSHA, signs that cutting fluids are no longer safe to use include:
1. Sump levels are low.
When sump levels fall below the 30% full mark, there has either been loss of cutting fluids, water evaporation, or both. This imbalance will affect the fluid concentration and deteriorate the quality of the cutting fluid.
2. Machines and trenches become dirty.
An unstable emulsion, depleted cleaners, fluid contaminants, or a filter failure can cause equipment and work surfaces to become soiled.
3. The fluid looks abnormal or contains floating matter.
If the fluid turns gray or black, this is a sign of bacteria. If the fluid turns yellow or brown, this is an indication of tramp oil. If the fluid’s dye begins to fade, this indicates the fluid is aging. Floating chips and swarf are also leading indicators that the fluid is becoming unsafe or that filtration equipment isn’t performing adequately.
4. The fluid emits a foul odor.
Fluid that smells bad is an indication of microbial growth. Microorganisms in the fluid can be aerosolized. Exposure to these microorganisms can lead to health problems.
5. Tramp oil is floating on the surface.
If sumps containing water-diluted fluids are completely covered with oil and an operator is unable to swish the oil out of the way for more than 5 to 8 seconds before the surface is covered by oil again, too much tramp oil may be present. Tramp oil is one of the leading causes of dermatitis in metalworking.
6. A lot of foam is present.
Excessive foam can be caused by fluid that is too highly concentrated, contaminated by cleaners, or contains soft water. An imbalance in the fluid surfactants or performance issues with the fluid system may also cause foam.
Getting to the Root of the Problem
Centralized fluid recycling systems automate the removal of tramp oils and suspended solids from contaminated metalworking fluids. These systems control bacteria and can adjust fluid concentration for fluid recovery. This approach to fluid maintenance not only minimizes employee exposure to spent fluids that can cause respiratory and dermatological health problems, but it also reduces new fluid purchases by 75% and decreases fluid disposal costs by approximately 90%.
Watch this video to learn how PRAB’s Guardian™ Coolant Recycling System recycles spent cutting fluid to reduce hazardous working conditions and decrease coolant spend.