• Record Type:
    OSHA Instruction
  • Current Directive Number:
    STD 01-05-012
  • Old Directive Number:
    STD 1-5.12
  • Title:
    29 CFR 1910.109, Explosives and Blasting Agents, Proposed Standards Modifications
  • Information Date:
  • Standard Number:





Subject: 29 CFR 1910.109, Explosives and Blasting Agents, Proposed Standards Modifications

1. Purpose

The purpose of this directive is to provide additional advisory information and guidance on proposed future changes to 29 CFR 1910.109.

2. Documentation Affected

This directive superseded Field Information Memorandum #75-48 dated September 2, 1975.

3. Background

a. Questions have arisen concerning standards promulgated in 29 CFR 1910.109, Explosives and blasting agents. Conflicts with other Federal agencies explosives regulations have been noted. OSHA is attempting to resolve these differences. In addition, clarification has been sought on the requirement specified in 29 CFR 1910.109(e)(1)(v) that all blasting operations shall be conducted during daylight hours. The latest edition of NFPA No. 495, the source for 29 CFR 1910.109, eases this requirement to reflect the unusual conditions which necessitate blasting at other times.
b. In view of these problem areas in 29 CFR 1910.109, we will propose to revise the entire section. We plan to incorporate the relevant revisions, of the NFPA code; resolve, where possible, major conflicts with other Federal agencies and modify the "use of explosives" paragraph. Changes such as the following will be proposed:


(1) The simultaneous transportation of blasting caps with other explosives on the same vehicle will be permitted under certain conditions. This is presently allowed by the Department of Transportation in 49 CFR 177.835(g).
(2) Major difference between explosives storage regulations in 29 CFR 1910.109(c) and those of the Alcohol, Tobacco, and Firearms Division, Internal Revenue Service, specified in 27 CFR Part 181, are being studied. It is planned to use Alcohol, Tobacco, and Firearms format (five types of storage facilities for explosives) with equivalent construction requirements. Present omissions in 29 CFR 1910. 109(c), such as unbarricaded distances in Table H-21, will be remedied.
(3) The scope of 29 CFR 1910.109 will be clarified to apply only to commercial explosives. It will not apply to the manufacture and storage of bombs, projectiles, or other encased explosives used in ordinance.
(4) Seismographic geophysical surveys for gas and oil exploration involving explosives and blasting will be covered under 29 CFR 1926, Construction standards.
(5) Blasting well be permitted at times other than during daylight hours, for unusual operations. Operations for blasting slag pockets and dustcatchers will fall within this category and will be permitted at night where proper illumination is provided and other appropriate requirements are met.
(6) All surface blasting operations shall be performed during daylight hours.
(7) Unusual blasting operations associated with industrial processes that are performed inside buildings shall be permitted regardless of time of day if both of the following conditions are met:
(a) All requirements concerning the use of explosives during normal blasting operations are implemented.
(b) A minimum illumination density of 20 foot candles is provided within a 5-foot radius of where explosive charges are being assembled, where explosive charges are being placed and where explosive materials are being attached to initiating devices.

OSHA Instruction STD 1-15.12 October 30, 1978


4. Action

Pending final approval of the proposed changes in the standards, any violation of a requirement of 29 CFR 1910.109 which is inconsistent with regulations promulgated by the Department of Transportation Standard or Alcohol, Tobacco, and Firearms Division, Internal Revenue Service, as discussed in paragraph 3.b., shall be considered de minimis, provided that the employer is in compliance with the relevant regulations of these agencies.

5. Effective Date

This directive is effective immediately and will remain in effect until the revised 29 CFR 1910.109 is promulgated.

Richard P. Wilson Deputy Director, Federal Compliance and State Programs.


A-1 E-1 B-2 HEW-1 C-1 NIOSH Regional Directors-1 D-4&5 NACOSH-1 Training Institute-4

(Originator: OCCS)