No. 4 Fuel Oil Ultra-Low Sulfur
A heavy distillate fuel oil classified under HTS 2710.19.06.05 due to its API gravity under 25 degrees, Saybolt Universal viscosity between 45 and 125 seconds at 37.8°C, and sulfur content not exceeding 500 ppm. It is primarily used for industrial boilers and marine applications where low-emission fuels are required. This specification meets stringent environmental regulations for reduced sulfur emissions.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If sulfur exceeds 500 ppm but ≤1,000 ppm
Higher sulfur content shifts to next sulfur tier subheading within same fuel oil category.
If for lubricating base oils
Products primarily for lubrication rather than fuel use fall under separate subheading for non-fuel oils.
If API gravity 25° or higher
Lighter oils with API ≥25° are classified separately from heavy testing under 25° fuels.
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Import Tips & Compliance
• Verify sulfur content via ISO 8754 or ASTM D4294 testing and include certificates in documentation
• Ensure viscosity and API gravity specs match exactly to avoid reclassification to higher subheadings
• Common pitfall: blending errors exceeding 500 ppm sulfur leading to duty adjustments
Related Products under HTS 2710.19.06.05
Marine No. 4-Type Fuel Oil Low Sulfur
Blended No. 4-type residual fuel oil for marine bunker use, with sulfur ≤500 ppm, viscosity 45-125 SUS at 37.8°C, and API <25°. Meets IMO low-sulfur standards under HTS 2710.19.06.05 for distillate/residual blends. Used in auxiliary engines on vessels requiring compliant heavy fuels.
Industrial Boiler No. 4 Fuel Oil 500 ppm S
Heavy fuel oil for stationary industrial boilers, specified as No. 4-type with ≤500 ppm sulfur, API under 25°, and 45-125 seconds Saybolt viscosity at 37.8°C per HTS 2710.19.06.05. Designed for high-efficiency combustion in manufacturing facilities complying with EPA sulfur limits.
Blended Residual No. 4 Fuel Oil Low S
A blend of distillate and residual oils forming No. 4 fuel with sulfur ≤500 ppm, <25° API, and viscosity 45-125 SUS, imported under HTS 2710.19.06.05. Suitable for older burners in commercial heating systems requiring ultra-low sulfur heavy fuel.
Power Plant No. 4 Type Fuel Oil ULS
Ultra-low sulfur (≤500 ppm) No. 4 fuel oil for backup generators in power plants, with Saybolt viscosity 45-125 sec at 37.8°C and API <25°, per HTS 2710.19.06.05 specs. Provides reliable heavy fuel for peak shaving operations.
Commercial Heating No. 4 Fuel 0.05% S
No. 4-type fuel oil with max 0.05% (500 ppm) sulfur for commercial building heating systems, API under 25°, 45-125 SUS viscosity, classified HTS 2710.19.06.05. Meets urban air quality standards for multi-burner installations.