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Questions and Answers

General Questions - Explosives

ATF is authorized to inspect the site of any accident or fire where there is reason to believe that explosive materials were involved. Other federal agencies, or state or local agencies, may also investigate such incidents, depending on the circumstances.

[18 U.S.C. 846(a); 27 CFR 555.31]

Black powder is an explosive material for purposes of federal explosives laws and regulations.

However, the law exempts from regulation commercially manufactured black powder in quantities not exceeding 50 pounds (as well as percussion caps, safety and pyrotechnic fuses, quills, quick and slow matches, and friction primers) intended to be used solely for sporting, recreational, or cultural purposes in antique firearms as defined in 18 U.S.C. 921(a)(16) or in antique devices exempted from the term "destructive device" in 18 U.S.C. 921(a)(4).

Regardless, persons engaged in the business of importing, manufacturing, or dealing in black powder in any quantity must have a federal explosives license, and comply with recordkeeping, storage and conduct of business requirements.

[18 U.S.C. 841(c), 841(d), 845(a)(5); 27 CFR 555.11: definitions of "explosives" and "explosive materials", 555.141(b)]

Small arms ammunition and components thereof that meet the definition of ammunition under the regulations is exempt.

[18 U.S.C. 845(a)(4), 27 CFR 555..11 : definition of “ammunition”, 555.141(a)(4)]

Until the compounds are mixed, they are not classified as explosives and, therefore, are not subject to control. However, once mixed, binary explosives are "explosive materials" and are subject to all applicable federal requirements.

A person who mixes or combines compounds of binary explosives for the purpose of sale or distribution or for the person’s own business use is a "manufacturer" of explosive materials and must be licensed as a manufacturer under the law.

[18 U.S.C. 841(h); 27 CFR 555.11: definition of "manufacturer"]

Can federal explosives disabilities resulting from a conviction of a crime punishable by imprisonment for a term exceeding one year be removed if the conviction is expunged or set aside or the convicted person has received a pardon for the offense or has had his or her civil rights restored?

A person convicted of, or under indictment for, a "crime punishable by imprisonment for a term exceeding one year" may not lawfully receive or possess explosive materials or be issued a federal explosives license or permit.

The term "crime punishable by imprisonment for a term exceeding one year" does not include offenses pertaining to antitrust violations, unfair trade practices, restraints of trade, or any state offense (other than one involving a firearm or explosive) classified as a misdemeanor and punishable by imprisonment for 2 years or less.

There are only 3 means by which federal explosives disabilities resulting from a conviction of, or indictment for, a "crime punishable by imprisonment for a term exceeding one year" can be removed:

  1. A decision of a court invalidating a conviction on the basis that the conviction was unconstitutional;
  2. In the case of a federal conviction, a presidential pardon; and
  3. The granting of relief from federal explosives disabilities by ATF pursuant to the filing of a relief application with the Director. For more information, visit our webpage Apply for Relief of Explosives Disability.

[18 U.S.C. 841(l), 842(d),(i), 845(b); 27 CFR 555.11: definition of "crime punishable by imprisonment for a term exceeding one year", 555.26(c), 555.142]

A UN (United Nations) number is used by the Department of Transportation (DOT) as a method of identification and classification of products for shipping purposes.

UN numbers are different from the hazard class or division designations used by DOT (for example, 1.1, 1.2, 1.3, 1.4, and 1.5). ATF regulations in 27 CFR Part 555 also use UN numbers to help identify certain explosives.

[27 CFR 555.11]

An EX number, preceded by the prefix "EX–", is issued and used by the Department of Transportation (DOT) to identify an explosive which has been tested and classified by DOT. See U.S. Department of Transportation regulations at 49 CFR 171.8 and 49 CFR 173.56.

Shock tube contains highly explosive material. However, it may be stored as a low explosive when not attached to a detonator.

[27 CFR 555.202(b), 555.213]

No. However, airport terminals and jetways (enclosed or open walkways on or above the tarmac) are considered inhabited buildings for table of distance requirements.

The term "highway" is defined in 27 CFR 555.11 as "any public street, public alley, or public road, including a privately financed, constructed, or maintained road that is regularly and openly traveled by the general public."

Privately financed, constructed or maintained roads that are not regularly or openly traveled by the general public do not fall within the meaning of the term and would, therefore, be exempt from table of distance requirements. See ATF Ruling 2005–2 for more information.

[27 CFR 555.11: definition of "highway"]

Yes. Federal explosives law prohibits any person from distributing explosive materials to persons under 21 years of age. However, it does not prohibit the delivery to or possession of explosive materials by persons under the age of 21 who are receiving or using the materials on behalf of their employers to whom the materials were lawfully sold.

[18 U.S.C. 842(d), (i); 27 CFR 555.11 (definition of "distribute"), 555.26, 555.106(b)(1)]

The Explosives List, also known as the Annual List of Explosive Materials, is a comprehensive (but not all-inclusive) listing of explosive materials which have been determined to be within the coverage of Chapter 40. The list is published annually by ATF in the Federal Register.

[18 U.S.C. 841(d); 27 CFR 555.23]

No. The actual transportation of explosive materials by carriers is subject to Department of Transportation or Department of Homeland Security regulations.

[18 U.S.C. 845(a)(1); 27 CFR 555.141(a)(1)]

Federal explosives laws and regulations generally prohibit any person from transporting explosive materials interstate or intrastate unless the person has a federal explosives license or permit. Also, the transportation of stolen explosives materials is a federal crime.

However, the law exempts from regulation under 18 U.S.C. Chapter 40 and 27 CFR Part 555 aspects of the transportation of explosive materials via railroad, water, highway or air which are regulated by the U.S. Department of Transportation, the Department of Homeland Security, and agencies thereof and which pertain to safety and security.

[18 U.S.C. 842(a)(3), 842(h), 845(a)(1); 27 CFR 555.26, 555.28, 555.141(a)(1)]

Gunsmiths

Yes. Licensed gunsmiths may make on-the-spot repairs at skeet, trap, target, and similar organized shooting events.

No, if the firearm is being returned to the person from whom it was received. However, if the firearm is delivered to someone other than the person from whom it was received, a NICS background check is required.

[18 U.S.C. 922(t); 478.124(a)]

Yes, a licensed gunsmith may receive a National Firearms Act (NFA) firearm for the sole purpose of repair and subsequent return to its owner.

It is suggested that the owner obtain permission from ATF for the transfer by submitting an ATF Form 5, Application for Tax Exempt Transfer and Registration of Firearm, to the NFA Branch and receive approval prior to the delivery. The gunsmith should do the same prior to returning the firearm.

Yes. A person conducting such activities as a business is considered to be a gunsmith within the definition of a dealer.

[18 U.S.C. 921(a)(11) and (21); 27 CFR 478.11]

Yes. Licensed gunsmiths are required to comply with written notification to unlicensed individuals upon delivery of a handgun. A gunsmith who transfers handguns to nonlicensees must also comply with the sign posting requirement.

[27 CFR 478.103]

No, provided the firearm is returned to the person from whom it was received.

[27 CFR 478.124(a) and 478.147]

If a firearm is brought in for repairs and the owner waits while it is being repaired, or if the gunsmith is able to return the firearm to the owner during the same business day, it is not necessary to list the firearm in the A&D record as an “acquisition.”

If the gunsmith has possession of the firearm from one business day to another or longer, the firearm must be recorded as an “acquisition” and a “disposition” in the A&D record.

Hiring Process (Special Agent)

Due to the large volume of applications processed by ATF, we will be unable to assist with individual status checks. Applicants are considered to be in the hiring process unless they receive written notification that they are no longer under consideration. As noted in each special agent vacancy announcement, the ATF hiring process can be very lengthy. Applicants are forwarded through the hiring process on an as needed basis and not on any set schedule. Budget issues, staffing issues and previously existing pool(s) of applicants may significantly affect the time it takes to complete the hiring process.

Under current hiring authority applicants apply to specific duty locations listed in the vacancy announcement. Application for duty location could change in the future based on changes in hiring authority.

All special agent applicants must take and pass the ATF special agent exam and an applicant assessment test. Results from an ATF sponsored exam are valid for three years from the date of the exam. Sample questions for the ATF special agent exam can be found at the “Careers” section of this website.

Unlike the private sector, federal agencies are required to announce, rate, rank, interview/assess and investigate applicants before they can be selected. All applicants must be given consideration too. Additionally, before an announcement is posted, Federal Human Resources professionals and the associated supervisor must work together to define and describe the position with a long narrative and then evaluate the description against Office of Personnel Management standards. Then qualification and assessment criteria must be professionally developed.

Selecting an individual for a federal position is a huge investment too. Over the course of a 30- year career, selecting an individual for a career appointment can be a multi-million-dollar investment. Federal jobs are not gigs; they are careers where individuals make a commitment to public service. To ensure someone is the best candidate for the job, multiple interviews and/or screenings may be needed.

Last Updated: January 21, 2026

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