The hidden cost of dirty diesel

Fuel contamination remains a significant threat to industrial equipment, worker safety, and environmental protection across various industries. We discover how this pervasive problem affects mechanical reliability and operational safety, creating substantial legal and financial liabilities.  

“Adulterated fuel is not just a matter of poor performance; it is a direct threat to equipment integrity, worker safety, and environmental sustainability,” says Craig FitzGerald, CEO of ISO-Reliability Partners. “The problem is far more prevalent than many realise and the consequences are escalating.”

When good fuel goes bad

The contamination typically involves mixing diesel with materials like illuminating paraffin (IP), used transformer oil, and gear oils, which severely compromise fuel standards. “IP, for instance, drastically reduces diesel’s lubricity, which is essential for the protection of high-pressure fuel injection systems. Without proper lubrication, you are essentially guaranteeing elevated costs, premature wear and mechanical failure,” explains FitzGerald.

Such contamination changes the fuel’s physical properties, including viscosity and density, which impairs combustion performance and reduces engine power output. This leads to more frequent maintenance requirements, unexpected equipment failures, and significantly higher operating expenses.

“We are seeing cases where seemingly minor dilution leads to major engine damage, simply because the physical and chemical properties of the fuel are no longer within operational parameters,” says FitzGerald.

More than just a bad burn

The safety risks go far beyond equipment damage. Used transformer oil frequently contains polychlorinated biphenyls (PCBs), which are toxic substances subject to strict international regulations under the Basel Convention.

“The combustion of PCBs in engines produces extremely harmful byproducts, including hydrogen chloride and dioxins, many of which are carcinogenic and mutagenic. When you are running adulterated fuel, you are creating chemical hazards that affect both operators and the broader environment,” FitzGerald emphasises.

Equipment reliability suffers as well, with poor-quality fuel potentially causing engine failures during operation. This can create dangerous situations, especially in heavy industrial or transportation environments.

Polluting profits and pockets

The practice creates environmental damage while undermining public finances. “This practice allows for the illegal disposal of hazardous industrial oils, leading to long-term soil, air, and groundwater contamination,” says FitzGerald. “It is a form of environmental abuse hiding in plain sight.”

The financial toll is enormous, with FitzGerald pointing out that South Africa loses over R3.6 billion annually from fuel contamination and related tax avoidance. “These are funds that could otherwise support environmental enforcement, infrastructure, and community development,” he adds.

Smart tech for dumb fuel

FitzGerald recommends combining technology with robust purchasing protocols to address contamination issues. Advanced monitoring systems like the Yateks Africa FuelTrust provide real-time detection of key fuel characteristics such as density, viscosity, and dielectric properties, enabling them to identify contaminants including paraffin and PCBs, as well as monitor moisture and temperature levels. These systems work particularly well for continuous surveillance in large-scale operations.

In addition to technological approaches it is crucial to maintain consistent fuel sampling, laboratory analysis, and verification against EN590 specifications. “Even when using unbranded or ‘white site’ fuel suppliers, it is critical to analyse lubricity and chemical composition to avoid surprises,” says FitzGerald.

Supplier side eye

ISO-Reliability Partners encourages industries to strengthen their fuel purchasing requirements. FitzGerald suggests requiring written confirmation of EN590 compliance or equivalent standards; requesting batch testing data for viscosity, density, and sulphur content; and establishing contractual audit rights. “Fuel suppliers must be held accountable. Choose branded suppliers with traceability and reputation to lose, as these are statistically far less likely to be involved in adulteration,” he advises.

He also stresses the importance of contractual safeguards: “Include clauses that enforce penalties for non-compliance, allow immediate termination if adulteration is detected, and mandate traceable sourcing. This creates both a legal and ethical deterrent.”

Legal leverage for liquid lies

Industries have robust legal options when contaminated fuel damages equipment – provided proper evidence exists. “If damage can be forensically linked to contaminated fuel, and a supplier is found to have breached contract or acted negligently, litigation is absolutely viable,” asserts FitzGerald.

South Africa’s legal framework provides substantial support: the National Environmental Management Act governs substances like PCBs, while the Consumer Protection Act supports claims involving defective or misrepresented fuel products. “Service-level agreements are key here,” says FitzGerald. “They provide the foundation for enforcing quality expectations and pursuing legal remedy.”

Government enforcement, too, is strengthening, with the Department of Mineral Resources and Energy documenting over 70 substandard fuel samples in recent inspections, supporting industry concerns and demonstrating regulatory recognition of the problem.

Fuel up on vigilance

With South Africa’s industrial sector facing economic pressures and environmental challenges, maintaining fuel quality has become essential. “The time for passive reliance on fuel suppliers is over. With the right tools, contracts, and vigilance, industries can protect their machinery, personnel, and the environment,” says FitzGerald.

“ISO-Reliability Partners is committed to helping clients implement these safeguards effectively. In an industry where fuel adulteration continues to threaten operational stability, the message is clear: awareness, action, and accountability must go hand in hand.”