You get your fuel test results back from the lab. There’s a table of numbers — flash point, cetane index, water and sediment, lubricity — each with a test method, a result, and a spec limit. Some have flags. What do they actually mean?
Most facility managers know they need . It’s required by for emergency power systems, referenced by surveyors, and built into . But very few people outside of fuel chemistry actually understand what the test results mean — or what to do when something comes back out of spec.
This guide changes that. We’ll walk through every ASTM D975 test parameter, explain what it measures in plain English, give you the pass/fail limits, and tell you exactly what to do if your fuel fails.
The stakes are real: Almost 1 in 3 generators fail when they’re actually needed. A regional hospital’s generator passed monthly run tests for three years. During a prolonged winter storm, it failed after 14 hours — fuel filters clogged with microbial contamination that had been growing silently for years. No annual fuel quality testing had been performed. The cost: emergency fuel polishing, patient transfer coordination, and a CMS investigation. An annual ASTM D975 test — which would have flagged the microbial growth and water contamination — costs a fraction of what that failure cost. And diesel fuel begins degrading within 28 days of delivery — meaning fuel sitting untested in your tank is changing every month.
Not sure if fuel quality testing even applies to your facility? — it identifies every regulation and test that applies, including ASTM D975.
What Is ASTM D975?
(current edition, approved May 2024) is the Standard Specification for Diesel Fuel, published by ASTM International. It defines seven grades of diesel fuel and establishes the minimum quality requirements each grade must meet.
ASTM D975 is not a single test. It’s a specification — a set of pass/fail limits that reference 13+ individual test methods. When your lab runs “ASTM D975 testing,” they’re performing a battery of individual tests and comparing each result to the D975 specification limits.
The most common grade for backup generators and stored fuel is No. 2-D S15 — the standard Ultra-Low Sulfur Diesel (ULSD) with a maximum sulfur content of 15 parts per million. That’s what this guide covers.
Why ULSD Changes the Game
If you’ve heard that “diesel used to last longer,” you’re right. Before 2006, highway diesel could contain up to 500 ppm sulfur. Today’s ULSD is capped at 15 ppm — a 97% reduction that was essential for emissions but created unintended consequences for stored fuel.
The hydro-treating process that strips sulfur also removes:
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Natural antioxidants — leaving fuel more vulnerable to oxidation
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Polar compounds that provided lubricity — increasing wear on fuel injection components
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Sulfur compounds with natural biostatic properties — removing a barrier to microbial growth
The result: modern ULSD is more susceptible to water absorption, faster to oxidize, and a better environment for bacteria and fungi than the diesel of 20 years ago. For facilities that store fuel for months between deliveries — which describes most backup generator installations — this matters enormously.
What to Look at First
Start with these four results — they’re the ones most likely to be out of spec in stored fuel, and the ones most likely to cause your generator to fail when you need it:
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Water and sediment (ASTM D2709) — The #1 failure in stored fuel. Water enables everything else that goes wrong.
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Microbial contamination (ASTM D6469/D7463) — Bacteria and fungi colonize the water-fuel interface and produce filter-clogging biomass.
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Oxidation stability (ASTM D2274) — Tells you whether your fuel has started to break down chemically.
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Particulate contamination (ASTM D6217/ISO 4406) — Invisible particles that destroy modern high-pressure injection systems.
If those four are clean, your fuel is almost certainly in good shape. If any are flagged, keep reading — the corrective actions section below tells you exactly what to do.
Every ASTM D975 Parameter Explained
Below is every parameter in the D975 specification for No. 2-D S15. We’ve organized them into two groups: parameters that commonly fail in stored fuel (the ones you’ll actually deal with) and parameters that rarely fail but matter when they do (usually indicating a supply chain problem, not a storage problem).
THE ONES THAT COMMONLY FAIL (Storage Degradation)
These parameters deteriorate over time in stored fuel. If your results are out of spec, it’s likely a storage management issue — and usually fixable.
Water and Sediment
| What it measures | Volume percentage of free water and solid particles, separated by centrifuge |
| Test method | (Centrifuge Method) |
| D975 limit | Maximum 0.05% by volume |
| If it fails | Water promotes microbial growth at the fuel-water interface, corrodes injectors, and plugs filters. Sediment causes abrasive wear on injectors and fuel pumps operating at 30,000+ PSI in modern common-rail systems. |
| Action | FuelCare’s service pumps off free water and separates emulsified water through multi-stage filtration. For heavier contamination, addresses water, sediment, and particulate in a single visit — without draining the tank. Install desiccant breathers on tank vents to prevent recurrence. Retest within 90 days. |
This is the most commonly failed parameter in stored fuel. Water enters through condensation on tank walls (temperature cycling), vent openings, poorly sealed fill caps, and dissolved water coming out of solution as temperatures drop. In states west of the Rockies, where humidity and temperature swings are a year-round reality, water management is the single most important factor in fuel quality.
Microbial Contamination
| What it measures | Presence of bacteria, fungi, and yeasts colonizing the fuel-water interface |
| Test methods | (guide), ASTM D7463 (ATP bioluminescence — rapid field test), ASTM D7978 (culture method) |
| Acceptable level | Negative for active microbial growth |
| If it fails | Microbial contamination (“diesel bug”) produces dark slimy growth, mucous on fuel filters, foul odor, and accelerated tank corrosion. The fungus Hormoconis resinae and various bacteria produce organic acids that corrode tank walls (even fiberglass), generate biomass that clogs filters, and degrade fuel quality. Key symptom: frequent or premature fuel filter plugging. |
| Action | FuelCare’s circulates biocide through the entire fuel volume — at shock dose for severe contamination or normal dose for moderate cases. Follow with to polish out dead biomass and remaining particulate. Ongoing prevention: quarterly CBT at light preventive dose, regular water draining, and ATP monitoring every 90 days. Note: killed microbes clog filters — expect multiple filter changes after treatment. |
ULSD’s reduced sulfur content eliminates the natural biostatic effect that older diesel provided. In states west of the Rockies — moderate temperatures and high humidity create year-round conditions for microbial growth. For more on why this matters for healthcare facilities, see .
Oxidation Stability
| What it measures | Fuel’s resistance to chemical degradation during storage (simulates ~1 year of aging) |
| Test method | (accelerated oxidation) |
| Generally accepted limit | Less than 1.5 mg/100 mL total insolubles |
| If it fails | Oxidized fuel forms gums, varnishes, and sediment that plug filters, coat injectors, and leave sticky residues. The fuel darkens and develops a sour odor. Once significant oxidation has occurred, it cannot be reversed. |
| Action | removes existing gums and oxidation products through multi-stage filtration. Follow up with regular to track degradation trends before they become critical. Severely oxidized fuel must be and replaced. Prevention is key: maintain regular fuel turnover, keep tanks full to minimize air exposure, and schedule quarterly VSR inspections to catch degradation early. |
Particulate Contamination
| What it measures | Mass and count of solid particles in fuel |
| Test method | (gravimetric) or ISO 4406 (particle count/cleanliness code) |
| Target cleanliness | ISO 4406 code of 18/16/13 or better |
| If it fails | Modern common-rail injection systems operate at up to 36,000 PSI with clearances of 2–5 microns. A human hair is ~80 microns; most damaging particles are invisible to the naked eye. Particles cause accelerated wear, injector erosion, and pump failure. |
| Action | uses portable polishing units with multi-stage filtration (down to 1 micron) and particle counters to verify cleanliness — all without draining the tank. For severe settled contamination, provides manual/mechanical interior cleaning. |
Acid Number (TAN)
| What it measures | Concentration of acidic compounds — a direct indicator of oxidative degradation |
| Test method | |
| Typical fresh diesel | Less than 0.08 mg KOH/g |
| Concern threshold | Above 0.10 mg KOH/g indicates degradation |
| If it fails | Acidic fuel corrodes metal tank surfaces, fuel lines, and injection components. Acids catalyze further oxidation — creating a degradation spiral. |
| Action | for mild elevation — removes acidic compounds and degradation byproducts. Replace fuel if significantly elevated. Check for microbial contamination, which produces organic acids as metabolic byproducts — treats the root cause. |
Lubricity (HFRR)
| What it measures | Fuel’s ability to protect fuel injection components from wear |
| Test method | (High Frequency Reciprocating Rig — measures wear scar on a steel ball) |
| D975 limit | Maximum 520 μm wear scar diameter |
| If it fails | ULSD is inherently low in lubricity because hydro-treating strips naturally lubricating compounds. Low lubricity accelerates wear on high-pressure fuel pumps and injectors. The Bosch CP4 pump is particularly vulnerable — documented U.S. failure rate of ~7% (vs. <1% in Europe, where the limit is 460 μm). CP4 failure is catastrophic: metal debris contaminates the entire fuel system, costing $8,000–$15,000+ to repair. |
| Action | Lubricity improver additives (fatty acid-based) are highly effective and inexpensive. Even B2 biodiesel blend significantly improves lubricity. This is one of the easiest and cheapest failures to prevent. |
THE ONES THAT RARELY FAIL (Supply Chain / Composition Issues)
These parameters are set at the refinery. If they’re out of spec, it’s almost always because something went wrong in the supply chain — wrong fuel delivered, cross-contamination during transport, or legacy residue in a tank. These failures are less common but more serious, because most can’t be fixed with treatment.
Flash Point
| What it measures | Lowest temperature at which fuel vapors ignite — a safety property |
| Test method | (Pensky-Martens Closed Cup) |
| D975 limit | Minimum 52°C (125°F) |
| If it fails | Safety hazard. Almost always caused by gasoline cross-contamination — even small amounts drop flash point dramatically. Switch-loading (sharing delivery trucks between gasoline and diesel) or manifolded vent systems connecting diesel and gasoline tanks are common sources. |
| Action | Fuel must be removed and replaced. No additive can raise flash point. Investigate the contamination source immediately. |
Distillation Temperature (90% Recovered)
| What it measures | Boiling range of the fuel — indicates proper composition and volatility |
| Test method | |
| D975 limit | 282–338°C (540–640°F) at 90% recovery |
| If it fails | Below 282°C suggests gasoline contamination (too many light ends). Above 338°C indicates heavy oil contamination or residual fuel blending. Either causes poor combustion, excessive smoke, carbon deposits, and reduced engine life. |
| Action | Fuel must be replaced or blended with on-spec fuel. This is a compositional issue — no additive corrects it. An out-of-range result warrants investigation of your supply chain. |
Kinematic Viscosity
| What it measures | Fuel’s resistance to flow — directly affects how well injectors atomize fuel |
| Test method | (at 40°C) |
| D975 limit | 1.9–4.1 mm²/s (centistokes) |
| If it fails | Below 1.9 cSt: poor lubrication of injection components, over-fueling from excessive injector leakage. Above 4.1 cSt: poor atomization, incomplete combustion, smoke, deposits, increased fuel system pressures. |
| Action | Low viscosity may indicate contamination with lighter fuels (kerosene, gasoline) — investigate and replace. High viscosity from oxidation can sometimes be corrected by blending with No. 1-D diesel. Severely out-of-spec fuel requires replacement. |
Sulfur Content
| What it measures | Total sulfur — critical for emissions compliance and exhaust aftertreatment protection |
| Test method | (UV Fluorescence) |
| D975 limit | Maximum 15 ppm (0.0015% by mass) for S15 grade |
| If it fails | Sulfur above 15 ppm in on-highway fuel is an EPA violation. It poisons diesel particulate filters (DPF) and selective catalytic reduction (SCR) catalysts, causing permanent damage. DPF replacement costs $2,000–$10,000+. |
| Action | Fuel must be disposed of and replaced. Investigate the supply chain for delivery errors or contamination from legacy high-sulfur fuel residues. There is no practical chemical or mechanical remedy for excess sulfur. |
Cetane Number
| What it measures | Ignition quality — how quickly and smoothly fuel ignites under compression. Think of it as the diesel equivalent of octane (but higher is better). |
| Test method | (CFR engine test) or (calculated cetane index) |
| D975 limit | Minimum 40 |
| If it fails | Hard starting (especially cold weather), diesel knock, white smoke on startup, excessive vibration, increased NOx emissions, and carbon buildup. These problems are amplified in cold climates — a concern for facilities in the Western U.S. during winter. |
| Action | Cetane improver additives (2-ethylhexyl nitrate) can raise cetane by 3–8 points. For severely low cetane, blend with higher-cetane fuel or replace. Note: calculated cetane index (D4737) cannot detect additive improvements — only the full D613 engine test can verify. |
Ash Content
| What it measures | Non-combustible metallic residue remaining after fuel is burned |
| Test method | |
| D975 limit | Maximum 0.01% by mass |
| If it fails | Abrasive wear on injector nozzles, piston rings, and cylinder liners. Deposit buildup on combustion chamber surfaces, exhaust valves, and turbocharger components. |
| Action | to remove particulates through multi-stage filtration. Investigate for tank corrosion products or improper additive blending. Replace fuel if significantly out of spec. |
Copper Strip Corrosion
| What it measures | Corrosiveness to copper alloys (present in fuel system bearings, fittings, and heat exchangers) |
| Test method | (polished copper strip immersed at 50°C for 3 hours) |
| D975 limit | Maximum No. 3 rating (scale: 1a = slight tarnish, 4c = corrosion) |
| If it fails | Active sulfur compounds attacking copper-alloy fuel system components — premature failure of fuel pump bearings, injector parts, and brass fittings. |
| Action | Replace fuel. Corrosive sulfur compounds are difficult to treat with additives. Biodiesel blends can sometimes contribute to elevated corrosion — check blend content. |
Cloud Point
| What it measures | Temperature at which wax crystals first appear as fuel cools — marks the onset of cold-weather operability problems |
| Test method | |
| D975 limit | Reported, not nationally specified — varies by region and season (buyer/seller agree) |
| If it fails for your climate | Wax crystals plug fuel filters, starving the engine. Generator cranks but won’t run, or loses power and stalls. For the Western U.S., winter cloud points should generally be below -12°C (10°F). |
| Action | Blending with No. 1-D diesel (kerosene) is the most effective way to lower cloud point. Cold flow improver (CFPP) additives can lower the operability point 5–15°F below cloud point but don’t change cloud point itself. Heated fuel lines and tank heating also help in extreme cold. |
Ramsbottom Carbon Residue
| What it measures | Tendency to form carbon deposits, tested on the heaviest 10% of the fuel |
| Test method | |
| D975 limit | Maximum 0.35% by mass |
| If it fails | Excessive deposits on injector tips (coking), piston crowns, and exhaust valves. Reduced spray pattern quality, increased emissions, power loss. Indicates contamination with heavier petroleum fractions or severe oxidative degradation. |
| Action | Mild cases may respond to detergent additives. Significantly out-of-spec fuel should be replaced. |
Conductivity
| What it measures | Fuel’s ability to dissipate static electrical charge during high-velocity pumping and transfer |
| Test method | |
| D975 limit | Minimum 25 pS/m when high-velocity transfer (>7 m/s) is involved |
| If it fails | ULSD naturally has very low conductivity. Without adequate conductivity, static charges accumulate during fast fuel transfer and can discharge as a spark — potentially igniting fuel vapors. This is primarily a safety concern during bulk delivery. |
| Action | Static dissipator additives (SDA) at very low treat rates (1–5 ppm) raise conductivity to safe levels. Typically added at the refinery or terminal but may dissipate over time in storage. |
Aromaticity
| What it measures | Percentage of aromatic hydrocarbons — affects combustion quality and emissions |
| Test method | (Fluorescent Indicator Adsorption) |
| D975 limit | Maximum 35% by volume |
| If it fails | High aromatics increase particulate/soot emissions, reduce cetane quality, and contribute to injector deposits. This is primarily a refining specification — not a storage degradation concern. |
| Action | Investigate fuel source. Not correctable by additive or polishing. |
How to Collect a Proper Fuel Sample
Bad samples produce bad results. Follow sampling procedures:
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Sample from the bottom of the lowest part of the tank. Collect 3–6 inches off the tank bottom — this is where water and sediment accumulate and where contamination is most detectable. A mid-tank sample represents bulk fuel quality but can miss bottom contamination entirely.
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Purge before collecting. Draw and discard a small volume from the sampling valve to clear stagnant fuel.
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Use clean, proper containers. Clear or amber borosilicate glass bottles, clean and dry. Fill 70–85% full (thermal expansion needs room). Seal immediately.
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Label everything. Date, time, tank ID, sampling location (top/middle/bottom), facility name, collector name.
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Ship promptly. Deliver to the lab within 24–48 hours. Keep out of direct sunlight during transport.
Reading Your Lab Report
A typical fuel quality lab report contains:
| Section | What It Shows |
|---|---|
| Sample identification | Your facility, tank ID, sample date, collection point |
| Results table | Each parameter tested, the test method used, the measured result, the D975 spec limit, and a pass/fail flag |
| Observations | Lab technician notes on sample appearance, odor, or condition at receipt |
| Recommendations | Suggested corrective actions based on out-of-spec results |
| Historical trending | Comparison with previous results from the same tank (if available) |
What to look for first: Water and sediment (D2709), microbial contamination, and oxidation stability. These three degrade progressively in stored fuel and are the leading causes of generator fuel system failure.
What a passing report means: Your fuel met specifications at the time of sampling. It does not mean the fuel will meet specifications 6 or 12 months from now — degradation is ongoing. This is why annual testing is a minimum, and quarterly monitoring is recommended best practice for critical facilities.
The Regulatory Requirement
NFPA 110
Section 8.3.7 mandates: “A fuel quality test shall be performed at least annually using appropriate ASTM standards.”
If annual testing reveals problems, NFPA 110 calls for additional testing every 90 days until results are acceptable. The standard also recommends sampling from the tank bottom to verify stored fuel is “as clean and dry as practicable.”
Joint Commission
references NFPA 110 and requires fuel quality verification. Surveyors will ask to see your lab reports during unannounced accreditation surveys. Missing documentation is treated as a presumption that testing was not performed.
What Missing Test Results Mean During an Inspection
If fuel quality test documentation is missing when an inspector or surveyor arrives:
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Deficiency citation will be issued
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A corrective action plan must be demonstrated
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For Joint Commission healthcare facilities, this can affect accreditation status
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Inspectors look for active fuel management — not just an annual test, but trending data, treatment logs, and corrective action records
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Repeated deficiencies can escalate to conditional accreditation
For the full picture of how fuel testing fits into the broader compliance landscape, see our .
What Testing Involves
Most facilities don’t need the full D975 battery every year. A stored fuel panel covering the parameters most likely to change during storage — water and sediment, microbial, stability, and particulate — provides the best value for ongoing monitoring. The full 13+ parameter battery is typically reserved for initial baseline testing or when contamination source investigation is needed.
FuelCare delivers all service results within 2 business days. Lab analysis turnaround depends on the third-party laboratory — typically 3–10 business days depending on lab load, tests required, and sample volume. Testing is often performed as part of a broader fuel management visit — FuelCare’s service includes on-site sample collection, visual fuel assessment, and lab submission, so you get both field observations and lab results in a single visit. All results and documentation are accessible through FuelCare’s client portal — permanent, regulator-ready records available anytime.
Pricing depends on the scope of testing, your facility’s location, number of tanks, and whether testing is bundled with treatment services. for a quote specific to your facility, or to understand where you stand.
Quick Reference: Corrective Actions by Failure Type
| Failure | Fixable? | FuelCare Service | What It Does | Prevention |
|---|---|---|---|---|
| Water contamination | Yes | Pumps water off tank bottom, separates emulsified water from fuel through multi-stage filtration. Significant contamination may require upgrading to higher intervention services like | Desiccant breathers, sealed fill caps, keep tanks full to reduce condensation surface | |
| Microbial growth | Yes | Circulates biocide through the entire fuel volume at calibrated dose rates (light, normal, or shock depending on severity). Kills bacteria and fungi at the fuel-water interface | Quarterly preventive biocide dosing, water removal, ATP monitoring every 90 days | |
| Particulate/sediment | Yes | High-intervention service: multi-stage filtration removes water, sediment, particulates, and microbial matter from stored fuel — without draining the tank. Portable polishing units with particle counters verify cleanliness | Scheduled TDC service visits, periodic tank cleaning, address root causes (corrosion, water) | |
| Severe contamination | Yes | Manual/mechanical cleaning of tank interior, sludge removal, and inspection. For cases where polishing alone can’t reach settled contamination | Ongoing fuel management program, regular VSR inspections | |
| Oxidation/instability | Partially | Polishing removes existing gums, varnishes, and oxidation products. Regular monitoring tracks degradation trends. Cannot reverse severe oxidation — fuel replacement may be needed | Maximize fuel turnover, keep tanks full to reduce air exposure, quarterly VSR inspections | |
| Low cetane | Yes | Additive treatment | Cetane improver added at calculated dose rate | Specify cetane requirements with fuel supplier |
| Low lubricity | Yes | Additive treatment | Lubricity improver or B2–B5 biodiesel blend | Use premium diesel or additive program |
| Low flash point | No | Fuel replacement + investigation | Fuel must be removed and . Investigate contamination source (shared delivery trucks, manifolded vents) | Verify supply chain, inspect vent systems |
| High sulfur | No | Fuel replacement | Remove and replace. No chemical or mechanical fix | Verify supplier, inspect for legacy high-sulfur residue in tank |
| Unknown / first test | N/A | On-site visual assessment, fuel sample collection from tank bottom, lab submission for ASTM D975 analysis. Establishes your baseline | Annual VSR at minimum (NFPA 110 requirement) |
How FuelCare’s services connect: A typical contamination scenario flows from VSR (discover the problem) → CBT (treat microbial growth) → TDC (polish out remaining contamination) → RFS (Residual Follow-up Service to verify remediation). For ongoing protection, quarterly preventive CBT at light dose rates keeps microbial growth in check between annual tests.
What You Should Do Now
Step 1: Check your records. When was your fuel last tested? If it’s been more than 12 months, you’re overdue under NFPA 110. FuelCare’s service includes on-site sample collection from the tank bottom, visual fuel assessment, and lab submission for ASTM D975 analysis — everything you need in a single visit.
Step 2: Know your risks. Facilities in the Western U.S. face specific challenges — high humidity drives water condensation, moderate temperatures support year-round microbial growth, and may impose additional requirements beyond federal standards.
Step 3: Understand your full compliance picture. ASTM D975 is one piece of a larger regulatory framework. Use to map every regulation that applies to your facility — it takes under 2 minutes.
Step 4: If fuel fails, act fast. Degradation compounds over time. Water enables microbial growth, which produces acids, which accelerate corrosion, which generates more sediment. The earlier you catch a problem, the cheaper and simpler the fix.
Frequently Asked Questions
How often should I test my stored diesel fuel?
NFPA 110 requires a minimum of annual fuel quality testing. However, for critical facilities — , , and other operations where generator failure has severe consequences — quarterly monitoring is recommended best practice. If annual testing reveals contamination or degradation, NFPA 110 calls for retesting every 90 days until results are acceptable.
What’s the difference between ASTM D975 and ASTM D6469?
ASTM D975 is the fuel specification — it defines the physical and chemical properties diesel fuel must meet (flash point, viscosity, cetane, sulfur, etc.). ASTM D6469 is the microbial contamination guide — it covers detection, monitoring, and control of bacteria, fungi, and yeasts in stored fuel. D975 tests the fuel itself; D6469 addresses the biological organisms that can colonize it. Most comprehensive fuel quality programs test for both.
Does a passing ASTM D975 test mean my fuel is good for another year?
No. A passing result means your fuel met specifications at the time of sampling. Diesel fuel degrades continuously — water accumulates, oxidation progresses, and microbial populations can grow significantly between annual tests. A passing result is a snapshot, not a guarantee. Annual testing is the minimum; ongoing monitoring (especially water checks and microbial screening) provides better protection for critical generators.
Which ASTM D975 parameters matter most for stored fuel?
For fuel that sits in a tank between deliveries (as most generator fuel does), the highest-risk parameters are: (1) Water and sediment (D2709) — the most commonly failed test and the root enabler of most other problems; (2) Microbial contamination (D6469/D7463) — grows at the water-fuel interface; (3) Oxidation stability (D2274) — indicates how much degradation has occurred; (4) Particulate contamination (D6217/ISO 4406) — measures filterable solids that can damage injection systems.
Can degraded diesel fuel be restored to ASTM D975 specifications?
It depends on what failed. Water contamination responds to Water Sediment Removal (WSR). Microbial growth is treated with Circulated Biocide Treatment (CBT). Particulate and sediment contamination is addressed by Tank Dialysis Clean (TDC) — which uses to restore fuel without draining the tank. Mild oxidation can be partially addressed. But some failures — low flash point (gasoline contamination), high sulfur, wrong viscosity or distillation range — indicate fundamental compositional problems that cannot be fixed. That fuel must be and replaced.
Related Posts
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— Overview of all federal, state, and industry regulations for fuel storage facilities
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— Healthcare-specific generator compliance requirements
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— SPCC thresholds, plan tiers, and top violations
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— Washington’s three-layer regulatory environment
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— Oregon DEQ’s single-program approach with mandatory licensed testers and 24-hour failure reporting
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— Real-world consequences of fuel neglect
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— Seasonal fuel maintenance guidance
FuelCare USA has provided , , and across the Western United States for over 25 years. for ASTM D975 testing or to find out which regulations apply to your facility.