August 26, 1981
MEMORANDUM FOR: DAVID H. RHONE
THRU: JOHN B. MILES FIELD COORDINATOR
FROM: BRUCE HILLENBRAND
FEDERAL COMPLIANCE AND STATE PROGRAMS
SUBJECT: Blasting and Use of Explosives Relative to
29 CFR 1926.905(h) and (k)
REFERENCE: Your memorandum dated July 22, 1981.
The requirement in 29 CFR 1926.905(h) "that equipment shall not be operated
within 50 feet of loaded holes" does not include equipment such as a backhoe
used in the placement of blasting mats. 29 CFR 1926.905(k) requires that no
drilling be performed within 50 feet of a loaded hole where the explosives
have failed to detonate. The regulations do not apply to holes which have
been filled with explosive in the initial loading.
Because 29 CFR 1926.905 does not regulate the distance between a loaded hole
and the drilling of the next hole, CSHO's will have to cite as a recognized
hazard section 5(a)(1) of the Act for drilling performed too close to a
loaded hole. For guidance in this matter, the Mine Safety and Health
Administration requires in Subchapter N-55.6-107 "Mandatory. Holes shall not
be drilled where there is danger of intersecting a charged or misfired hole".