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Air Emission Measurement Center (EMC)

EMC Conditional Test Methods

This category includes methods that were categorized as conditional test methods before our method categories were revised. Because some of these methods have been cited in state rules and permits under their Conditional Test Method (CTM) designation, we have created a category for them and called it "Historic Conditional Methods". This category is closed and no new methods will be added to it.

These CTMs have been evaluated by the Agency and may be applicable to one or more categories of stationary sources. The EPA confidence in a method included in this category is based upon review of various technical information including, but not limited to, field and laboratory validation studies; EPA understanding of the most significant quality assurance (QA) and quality control (QC) issues; and EPA confirmation that the method addresses these QA/QC issues sufficiently to identify when the method may not be acquiring representative data. The method's QA/QC procedures are required as a condition of applicability.

CTMs may be used by State and local programs in conjunction with Federally enforceable programs (e.g., Title V permits, State Implementation Plans (SIP)) provided they are subject to an EPA Regional SIP approval process or permit veto opportunity and public notice and opportunity for comment. They are available for application without EPA oversight for other non-EPA program uses including state permitting programs and scientific and engineering applications.

These methods must be approved as alternatives before a source may use them to meet Federal requirements under 40 CFR Part 60, 61, and 63. The EPA encourages the submission of additional field and laboratory data to further support a method.

The EPA staff may not necessarily be the technical experts on these methods. These methods are potentially subject to change based on the review of additional validation studies or on public comment as a part of adoption as a method proposed or promulgated in the Federal Register.

The documents below are PDFs, except where indicated. You will need Adobe Reader to view the files on this page. See EPA’s About PDF page to learn more.

CTM# Title Date
CTM-001 Butadiene Method (8 pp, 38 K) February 1989
CTM-002 Particulate (PM Screening) Method (10 pp, 60 K)
Particulate (PM Screening) Figure (1 pg, 12 K)

May 1989

CTM-003 Particulate (PM Modified High Volume) Method (15 pp, 142 K) September 1989
CTM-008 Conditional Test Method for Acrylonitrile (10 pp, 881 K)  
CTM-010 Perchloroethylene in Wet Waste (Filters and Still Bottoms) (7 pp, 37 K) March 1991
CTM-011 Halogenated Organics Method (13 pp, 44 K) May 1991
CTM-013 Determination of Sulfuric Acid Vapor or Mist and Sulfur Dioxide Emissions from Kraft Recovery Furnaces (87 pp, 5 MB) December 1996
CTM-013A Determination of Sulfuric Acid and Sulfur Dioxide Emissions from Combination Fuel Boilers and Recovery Furnaces (9 pp, 327 K) December 1996
CTM-013B Determination of Sulfuric Acid and Sulfur Dioxide Emissions from Combination Boilers, Recovery Furnaces, and Thermal Oxidizers - Isokinetic Method (8 pp, 115 K) December 1996
CTM-014 Benzene Matter Emissions (14 pp, 50 K) December 1992
CTM-019 Gas Velocity and Volumetric Flowrate under Cyclonic Flow Conditions (10 pp, 64 K) June 1986
CTM-022 Nitric Oxide, Nitrogen Dioxide, & NOx emissions by Electrochemical Analyzer May 1995
CTM-025 Microbial Survivability Test for Medical Waste Incinerator Ash (14 pp, 46 K) August 1990
CTM-026 Microbial Survivability Test for Medical Waste Incinerator Emissions (18 pp, 303 K)  
The validation report for this method can be found in the "Field Test of Ammonia Collection Analysis Method." (34 pp, 3 MB)
August 1997
CTM-028 Direct Interface GC/MS Performance-Based Method (16 pp, 63 K) October 1997
CTM-029 Asbestos in Serpentine Aggregate - CARB Method 435 (24 pp, 123 K) June 1991
Note: Please note that there is an ASTM Method (ASTM D6522-00) that is similar to this conditional test method.
We strongly encourage you to consider its use in accordance with the applicability as specified in the method.
October 1997
CTM-031 Screening Method for Methylene Diphenyl Diisocyanate (MDI) (8 pp, 29 K)  
CTM-032 Draft Method for Sampling and Analysis for High Levels of Phenol and Cresol Emissions from Stationary Sources (52 pp, 503 K)  
Note: CTM-033 has been revised and is now OTM-29 (33 pp, 377 K). The method was updated to address issues related to maintaining a pH of 12 and higher in the NaOH impingers during the test.
CTM-034 Draft Method for the Determination of O2, CO, & (NO and NO2) for Periodic Monitoring (23 pp, 94 K) September 1999
CTM-035 Determination of Low Concentration Non-Methane Non-Ethane Organic Compound Emissions From Clean Fueled Combustion Sources (57 pp, 653 K)  (SCAQMD Method 25.3) March 2000
CTM-036 Method for Sampling Isocyanate Stack Emissions (Revised 03/05) (9 pp, 1 MB) March 2005
CTM-036A Method for Analyzing Isocyanate Stack Emissions (Revised 02/04) (11 pp, 260 K) February 2004
Acetyl Acetone Derivatization Method" has been finalized as Method 323 - Formaldehyde Measurement Using Derivatization
CTM-038 Measurement of Ammonia Emissions From Highway, Nonroad, and Stationary Use Diesel Engines by Extractive Fourier Transform Infrared (FTIR) Spectroscopy (113 pp, 145 K)  
Measurement of PM 25 and PM 10 Emissions by Dilution Sampling (Constant Sampling Rate Procedures) (77 pp, 259 K)
This Windows Media Movie provides a visualization of the hardware associated with the method described in Conditional Test Method 39.
The file size of this movie is large (50 M) and requires the Windows Media viewer.
July 2004
CTM-041 Determination of Volumetric Gas Flow in Rectangular Duct or Stacks Taking Into Account Velocity Decay Near the Stack or Duct Walls (17 pp, 121 K)
January 2003
CTM-042 Use of Flame Ionization Detector-Methane Cutter Analysis Systems for VOC Compliance Testing of Bakeries (Revised 08/04) (11 pp, 247 K) August 2004
Note: Please note that there is now an Annex to an ASTM Method (Annex 1 to ASTM D6216-07) that updates this method and more completely addresses low opacity measurement.
We strongly recommend that you consider its use in lieu of CPS-001.