An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Methods Innovations Rule (MIR) & Method Defined Parameters (MDPs)

EPA received many questions about hazardous waste test methods. The questions and responses for this category are listed below.

On this page:

What is the status of Update VI to SW-846?

What is the status of Update VI? When will these methods be finalized?

The Office of Resource Conservation and Recovery is currently working on Update VI to SW-846. The Agency plans to publish Update VI in three phases: Update VIA, Update VIB, and Update VIC, where one phase will include several organic methods (e.g., 8260D and 8270E), another phase will include several inorganic methods (e.g., 3050C and 6200A), and the remaining phase will include LEAF methods 1313, 1314, 1315, and 1316 along with a LEAF guidance document. Publication dates and specific methods are not certain, but publication will likely not occur before the calendar year 2016.

Other Category: General

Top of Page

What is the current process to promulgate SW-846 test methods?

I understand the process has changed in promulgating SW-846 test methods. How are they promulgated? When are they finally approved for use?

Currently, many RCRA regulations specifically require the use of SW-846 methods. Methods are added to the SW-846 methods compendium by two ways. Required methods are added to SW-846 through a formal rulemaking process, in which the Agency follows the Action Development Process (ADP), through which the agency seeks notice and comment. After the comments are reviewed, the required method may be revised, based on public comment. Then Agency will finalized the methods with a Final rule after the designated comment period. Only after a final rule is published are methods approved for use by the regulated community in order to comply with RCRA regulations requiring the use of finalized SW-846 methods. States may choose to adopt the required method(s).

For all other methods considered guidance, updates to SW-846 are announced through a Notice of Availability (NOA). These validated methods are made available to the public for comment. After comments are evaluated, the agency will revise the method update appropriately. Once the methods are finalized, the update is incorporated into the SW-846 method compendium.

Other Categories: General, PBMS & Flexible Approach

Top of Page

Use of non-required test methods for compliance with the Resource Conservation and Recovery Act (RCRA) regulations in relation to the Methods Innovation Rule (MIR).

How can one determine when a non-required method is appropriate to use for compliance with RCRA in relation to the Methods Innovation Rule?

If the analysis that you wish to perform is not for one of the Method Defined Parameters (MDPs) listed in 40 CFR §260.11, then you must determine whether a method (whether SW-846 or not) is appropriate for the analytical purpose. The Agency has written the following guidance in the MIR for determining method appropriateness:

An appropriate method might be one published by:

  • EPA in a different manual or regulation;
  • Another government agency;
  • A voluntary standards setting organization; or
  • Other well-known source.

Appropriate methods are reliable and accepted as such in the scientific community. These methods might include those published by the Agency or other government entities using techniques that have documented reliability (e.g., ASTM).

Appropriate methods generate effective data, known and of appropriate quality for project-specific decisions.

When selecting an appropriate method to use, you must be able to demonstrate and document that you are able to see the analyte of concern, in the matrix of concern, at the level of concern.

In addition, before selecting an alternative method other than SW-846 for RCRA-related testing and monitoring activities, we recommend that you discuss your plans with your regulating authority and the project managers.

Other Categories: General, PBMS & Flexible Approach

Top of Page

Does the Methods Innovation Rule (MIR) add any new requirements to the Resource Conservation and Recovery Act (RCRA) regulations?

No, the MIR did not add new testing or information collection and reporting requirements to the regulations.

Top of Page

Can you still use SW-846 when it is appropriate to do so in relation to the Methods Innovation Rule (MIR)?

Yes, the Agency also refers to SW-846 methods, and any appropriate method may be used for waste characterization and analysis. Most methods in SW-846 are guidance. However, some of the regulations require the use of a specific SW-846 methods (Methods Defined Parameters (MPDs)). For a list of the required SW-846 methods, see: 40 CFR Part 260.11.

Top of Page

Do the "flexible approach", performance based measurement system (PBMS), and/or Methods Innovation Rule (MIR) change the way prescriptive language is interpreted in SW-846 methods?

Do the "flexible approach", performance based measurement system (PBMS), and/or Methods Innovation Rule (MIR) change the way prescriptive language is interpreted when encountered in SW-846 methods?

The following statement from the Disclaimer for SW-846 provides specific guidance for interpretation of must, should, etc.:

"EPA generally does not intend these methods to be overly prescriptive. The words "shall," "must," or "require" are used to indicate aspects of the method that are considered essential to its performance, based on sound analytical practices (e.g., an instrument must be calibrated before use). In contrast, the words "should," "may," or "recommend" are used to provide guidance on aspects of the method that are useful but not essential. This flexibility does not apply to those Method Defined Parameters where the analytical result is wholly dependent on the process used to make the measurement."

Other Categories: General, PBMS & Flexible Approach

Top of Page

What are the SW-846 methods that are Method Defined Parameters (MDPs)?

The SW-846 methods that are MDPs are:

  • 0010, Modified Method 5 Sampling Train
  • 0011, Sampling for Selected Aldehyde and Ketone Emissions from Stationary Sources
  • 0020, Source Assessment Sampling System (SASS)
  • 0023A, Sampling Method for Polychlorinated Dibenzo-p-Dioxins and Polychlorinated Dibenzofuran Emissions from Stationary Sources
  • 0030, Volatile Organic Sampling Train
  • 0031, Sampling Method for Volatile Organic Compounds (SMVOC)
  • 0040, Sampling of Principal Organic Hazardous Constituents from Combustion Sources Using Tedlar® Bags
  • 0050, Isokinetic HCl/Cl2 Emission Sampling Train
  • 0051, Midget Impinger HCl/Cl2 Emission Sampling Train
  • 0060, Determination of Metals in Stack Emissions
  • 0061, Determination of Hexavalent Chromium Emissions from Stationary Sources
  • 1010A, Test Methods for Flash Point by Pensky-Martens Closed-Cup Tester
  • 1020B, Standard Test Methods for Flash Point by Setaflash (Small Scale) Closed-Cup Apparatus
  • 1110A, Corrosivity Toward Steel
  • 1310B, Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test
  • 1311, Toxicity Characteristic Leaching Procedure
  • 1312, Synthetic Precipitation Leaching Procedure
  • 1320, Multiple Extraction Procedure
  • 1330A, Extraction Procedure for Oily Wastes
  • 9010C, Total and Amenable Cyanide: Distillation
  • 9012B, Total and Amenable Cyanide (Automated Colorimetric with Off-Line Distillation)
  • 9040C, pH Electrometric Measurement
  • 9045D, Soil and Waste pH
  • 9060A, Total Organic Carbon
  • 9070A, n-Hexane Extractable Material (HEM) for Aqueous Samples
  • 9071B, n-Hexane Extractable Material (HEM) for Sludge, Sediment, and Solid Samples
  • 9095B, Paint Filter Liquids Test

The regulation that lists all MDPs can be found at 40 CFR 260.11

Top of Page

What does Method Defined Parameter (MDP) mean?

Method-defined parameters are physical or chemical properties of materials determined with specific methods used to evaluate whether the materials comply with certain RCRA Subtitle C regulations. Method-defined parameters can only be determined by the methods prescribed in RCRA regulations because the methods are part of the regulations. These methods (listed below) must be followed exactly as written, or the resulting data cannot be used to ensure regulatory compliance. In addition to the table below, a list of method-defined parameters may be found at 40 CFR part 260.11.

Top of Page

How did the Methods Innovation Rule affect SW-846 and the Resource Conservation and Recovery Act (RCRA)?

The Methods Innovations Rule (MIR) included the following revisions to SW-846:

Certain SW-846 testing regulations allow the use of other practical test methods, so long as they fall within EPA’s parameter to protect human health and the environment. Some required uses of SW-846 methods remain in the regulations because they involve determination of method-defined regulatory parameters.

  • Finalized proposed revisions to Update IIIB to the Third Edition of SW-846;
  • Removed requirements to use Chapter Nine, “Sampling Plan” in certain circumstances;
  • Amended Sections 7.3.3 and 7.3.4 of SW-846 Chapter Seven to withdraw the cyanide and sulfide reactivity guidance as well as required uses of reactive cyanide and sulfide methods; and threshold levels from conditional delistings.

The MIR affects RCRA in the following ways:

  • Makes the RCRA program more effective by focusing more on measurement objectives rather than measurement technologies;
  • Provides flexibility to the regulated community by allowing the use of other methods than SW-846 for RCRA testing and monitoring activities when it is appropriate to do so;
  • Offers the use of other appropriate methods as an option. The Agency expects individuals to choose other appropriate methods only when it is more beneficial to do so; and
  • Allows greater flexibility in method selection, which should stimulate the development and use of innovative and more cost-effective monitoring technologies in the RCRA program.

Top of Page

What is the Methods Innovation Rule (MIR)?

On June 14, 2005 EPA published the Methods Innovation Rule (MIR) (70 FR 34538-34592). The MIR allows for more flexibility in the use of alternative methods outside of those listed in EPA publication, SW-846, Test Methods for Evaluating Solid Waste, Physical/Chemical Methods. This document is the Agency's official compendium of analytical and sampling methods that have been evaluated and approved for use in complying with regulations under the Resource Conservation and Recovery Act (RCRA).

This rule clarified the difference between SW-846 methods that are required and those that are intended as guidance methods. In addition, some required uses of SW-846 methods – known as Method Defined Parameters (MDPs) – remain regulated in situations where a particular procedure is the only one capable of properly measuring for sampling and analysis. The Agency finalized Update IIIB to the Third Edition of SW-846, and removed unnecessarily required uses of Chapter Nine, "Sampling Plan." In addition, this rule amended Sections 7.3.3 and 7.3.4 of SW-846, Chapter Seven, to withdraw the cyanide and sulfide reactivity guidance. The required uses of reactive cyanide and sulfide methods and threshold levels from conditional delistings were also removed.

Top of Page