D001 hazardous waste code

Characteristic of ignitability
Revised as of July 1, 2025

40 CFR 261.21 gives EPA Hazardous Waste Number D001 to a solid waste that exhibits the characteristic of ignitability. The section is below as the regulation prints it.

Characteristic of ignitability

40 CFR 261.21
Revised as of July 1, 2025

40 CFR 261.21 gives EPA Hazardous Waste Number D001 to a solid waste that exhibits the characteristic of ignitability. The section is below as the regulation prints it.

§ 261.21 Characteristic of ignitability.

(a) A solid waste exhibits the characteristic of ignitability if a representative sample of the waste has any of the following properties:

(1) It is a liquid, other than a solution containing less than 24 percent alcohol by volume and at least 50 percent water by weight, that has a flash point less than 60 °C (140 °F), as determined by using one of the following ASTM standards: ASTM D93-79, D93-80, D3278-78, D8174-18, or D8175-18 as specified in SW-846 Test Methods 1010B or 1020C (all incorporated by reference, see § 260.11 of this subchapter).

(2) It is not a liquid and is capable, under standard temperature and pressure, of causing fire through friction, absorption of moisture or spontaneous chemical changes and, when ignited, burns so vigorously and persistently that it creates a hazard.

(3) It is an ignitable compressed gas.

(i) The term “compressed gas” shall designate any material or mixture having in the container an absolute pressure exceeding 40 p.s.i. at 70 °F or, regardless of the pressure at 70 °F, having an absolute pressure exceeding 104 p.s.i. at 130 °F; or any liquid flammable material having a vapor pressure exceeding 40 p.s.i. absolute at 100 °F as determined by ASTM Test D-323.

(ii) A compressed gas shall be characterized as ignitable if any one of the following occurs:

(A) Either a mixture of 13 percent or less (by volume) with air forms a flammable mixture or the flammable range with air is wider than 12 percent regardless of the lower limit. These limits shall be determined at atmospheric temperature and pressure. The method of sampling and test procedure shall be the ASTM E 681-85 (incorporated by reference, see § 260.11 of this subchapter), or other equivalent methods approved by the Associate Administrator, Pipeline and Hazardous Materials Safety Administration, U.S. Department of Transportation.

(B) It is determined to be flammable or extremely flammable using 49 CFR 173.115(l).

(4) It is an oxidizer. An oxidizer for the purpose of this subchapter is a substance such as a chlorate, permanganate, inorganic peroxide, or a nitrate, that yields oxygen readily to stimulate the combustion of organic matter.

(i) An organic compound containing the bivalent -O-O- structure and which may be considered a derivative of hydrogen peroxide where one or more of the hydrogen atoms have been replaced by organic radicals must be classed as an organic peroxide unless:

(A) The material meets the definition of a Division 1.1, 1.2, or 1.3 explosive, as defined in § 261.23(a)(8), in which case it must be classed as an explosive,

(B) The material is forbidden to be offered for transportation according to 49 CFR 172.101 and 49 CFR 173.21,

(C) It is determined that the predominant hazard of the material containing an organic peroxide is other than that of an organic peroxide, or

(D) According to data on file with the Pipeline and Hazardous Materials Safety Administration in the U.S. Department of Transportation, it has been determined that the material does not present a hazard in transportation.

(b) A solid waste that exhibits the characteristic of ignitability has the EPA Hazardous Waste Number of D001.

CERCLA hazardous substances

40 CFR 302.4
Revised as of July 1, 2025

Table 302.4 of 40 CFR 302.4, the list of CERCLA hazardous substances, prints RCRA waste number D001 in one row, shown below with its final reportable quantity.

Table 302.4—List of Hazardous Substances and Reportable Quantities

Hazardous substance	CASRN^I	Statutory code^II	RCRA waste No.	Final RQ [pounds (kg)]
Unlisted Hazardous Wastes Characteristic of Ignitability	N.A.	4	D001	100 (45.4)

Notes to Table 302.4—List of Hazardous Substances and Reportable Quantities, as the regulation prints them

Note I to Table 302.4 The numbers under the column headed “CASRN” are the Chemical Abstracts Service Registry Numbers for each hazardous substance. CASRNs are unique numeric identifiers for specific substances. CASRNs are updated by the Chemical Abstract Service and are sometimes deleted or replaced. This list of CERCLA hazardous substances relies on information provided in the statutory lists that comprise the table. CASRNs are provided for convenience only to aid in the identification of the designated hazardous substance. Some CASRNs are given only for parent compounds. In some cases, a chemical name may have more than one CASRN associated with it due to the chemical's various forms; however, each CAS Registry Number is a unique numeric identifier and designates only one substance. That is, two substances, or two forms of a substance, do not have the same CAS Registry Number. If there is a discrepancy between the hazardous substance name and the listed CAS Registry Number, the hazardous substance names appearing in Table 302.4 should be used as the official means to determine if a given chemical or substance is reportable.

Note II to Table 302.4 Hazardous substances are given a Statutory Code based on their statutory source. The “Statutory Code” column indicates the statutory source for designating each substance as a CERCLA hazardous substance. Statutory Code “1” indicates a Clean Water Act (CWA) Hazardous Substance [40 CFR 116.4; 33 U.S.C. 1321(b)(2)(A)]. Statutory Code “2” indicates a CWA Toxic Pollutant [40 CFR 401.15, 40 CFR part 423 Appendix A, and/or 40 CFR 131.36; 33 U.S.C. 1317(a)]. Statutory Code “3” indicates a CAA HAP [42 U.S.C. 7412(b); Pub. L. 101-549 November 15, 1990; 70 FR 75047 December 19, 2005; 69 FR 69320 November 29, 2004; 61 FR 30816 June 18, 1996; 65 FR 47342 August 2, 2000; 87 FR 393 January 5, 2022]. Statutory Code “4” indicates Resource Conservation and Recovery Act (RCRA) Hazardous Wastes [40 CFR part 261 Subpart D—Lists of Hazardous Wastes; 42 U.S.C. 6921]. (Note: The “RCRA waste No.” column provides the waste identification numbers assigned by RCRA regulations). Statutory Code “5” indicates a hazardous substance designated under section 102(a) of CERCLA. The “Final RQ [pounds (kg)]” column provides the reportable quantity for each hazardous substance in pounds and kilograms.

^I Provides reference to Note I to Table 302.4 to discuss the applicability of CASRNs.

^II Indicates the statutory source defined by 1, 2, 3, and 4, as described in the Note II to Table 302.4.

^III No reporting of releases of this hazardous substance is required if the diameter of the pieces of the solid metal released is larger than 100 micrometers (0.004 inches).

^IV The RQ for asbestos is limited to friable forms only.

^v The Agency may adjust the statutory RQ for this hazardous substance in a future rulemaking; until then the statutory one-pound RQ applies.

## The Agency may adjust the statutory RQ for this hazardous substance in a future rulemaking; until then the statutory one-pound RQ applies.

§ The adjusted RQs for radionuclides may be found in appendix B to this table.

** Indicates that no RQ is being assigned to the generic or broad class.

^a Benzene was already a CERCLA hazardous substance prior to the CAA Amendments of 1990 and received an adjusted 10-pound RQ based on potential carcinogenicity in an August 14, 1989, final rule (54 FR 33418). The CAA Amendments specify that “benzene (including benzene from gasoline)” is a hazardous air pollutant and, thus, a CERCLA hazardous substance.

^b The CAA Amendments of 1990 list DDE (3547-04-4) as a CAA hazardous air pollutant. The CAS number, 3547-04-4, is for the chemical, p,p′dichlorodiphenylethane. DDE or p,p′-dichlorodiphenyldichloroethylene, CAS number 72-55-9, is already listed in Table 302.4 with a final RQ of 1 pound. The substance identified by the CAS number 3547-04-4 has been evaluated and listed as DDE to be consistent with the CAA section 112 listing, as amended.

^c Includes mineral fiber emissions from facilities manufacturing or processing glass, rock, or slag fibers (or other mineral derived fibers) of average diameter 1 micrometer or less.

^d Includes mono- and di-ethers of ethylene glycol, diethylene glycol, and triethylene glycol R-(OCH2CH2)n-OR′ where:

n = 1, 2, or 3;

R = alkyl C7 or less; or

R = phenyl or alkyl substituted phenyl;

R′= H or alkyl C7 or less; or

OR′ consisting of carboxylic acid ester, sulfate, phosphate, nitrate, or sulfonate.

^e Includes organic compounds with more than one benzene ring, and which have a boiling point greater than or equal to 100 °C.

^f See 40 CFR 302.6(b)(1) for application of the mixture rule to this hazardous waste.

Other sections of 40 CFR part 261, and its Appendix IX, can change whether a waste carries this code. They are not copied here.

For a federal hazardous waste code the regulation governs. This page copies the Code of Federal Regulations' annual edition revised as of July 1, 2025, which is kept up to date by the Federal Register; amendments published there since that date are not shown. This page is a reference copy and not a waste determination. Check the current regulation before relying on it.

Source

Environmental Protection Agency, 40 CFR part 261, in Title 40 of the Code of Federal Regulations, Parts 260 to 265, revised as of July 1, 2025, as the U.S. Government Publishing Office posts it. File read October 6, 2026.
Environmental Protection Agency, 40 CFR 302.4, in Title 40 of the Code of Federal Regulations, Parts 300 to 399, revised as of July 1, 2025. File read October 6, 2026.