API Publ 4611 is a technical API document that addresses an interlaboratory study of EPA Methods 1662, 1654A, and 1663 for determining diesel, mineral, and crude oils in drilling muds from offshore and gas industry discharges. For buyers evaluating relevance, it provides a focused reference for understanding how these analytical methods were assessed in a practical testing context. API Publ 4611 is most useful where consistency in environmental sample analysis, method comparison, or technical review matters to offshore and gas operations, helping teams align documentation and quality expectations around oil-in-mud determinations.

What is API Publ 4611?

API Publ 4611 is an API Document published in 1995 as a technical reference on interlaboratory evaluation of EPA analytical methods related to oil detection in drilling muds. Based on the official title, it is not a field procedure manual, but a document centered on laboratory method performance and comparative study results. As a published API reference, it may support technical review, data interpretation, and method selection discussions where environmental monitoring or discharge testing is involved. API Publ 4611 is therefore a practical benchmark document for teams needing a structured view of the methods named in the title.

Where is API Publ 4611 used?

API Publ 4611 is typically relevant in offshore drilling, gas industry discharge monitoring, and related environmental testing workflows where drilling mud samples may need laboratory analysis for oil content. It may be reviewed by environmental, operations, QA/QC, and technical documentation teams, as well as by laboratory personnel supporting method validation or comparison work. In practice, the document can help align internal review of test data, discharge-related reporting, and procurement of reference materials or analytical services tied to the methods named in the title.

Why is API Publ 4611 important?

API Publ 4611 matters because it gives professionals a clear technical reference for understanding how specific EPA methods performed across laboratories when applied to drilling mud matrices. That can support more consistent interpretation of analytical results, better method awareness during project planning, and stronger quality control in environmental compliance work. For engineering, operations, and procurement teams, API Publ 4611 helps reduce ambiguity when evaluating test reports, selecting laboratory support, or documenting due diligence around offshore and gas industry discharge analysis.

• Interlaboratory study reference
• EPA methods 1662, 1654A, and 1663
• Diesel, mineral, and crude oil analysis
• Drilling mud and discharge testing context
• Useful for QA/QC and technical review teams
• Supports environmental and laboratory documentation