---
kind: "section"
citation: "30 C.F.R. § 57.6407"
title: "30"
number: "57.6407"
heading: "Circuit testing."
url: "https://uscodex.org/cfr/30/57.6407"
---

# §57.6407. Circuit testing.


A blasting galvanometer or other instrument designed for testing blasting circuits shall be used to test the following:

- (a) **In surface operations—**
  - (1) Continuity of each electric detonator in the blasthole prior to stemming and connection to the blasting line;
  - (2) Resistance of individual series or the resistance of multiple balanced series to be connected in parallel prior to their connection to the blasting line;
  - (3) Continuity of blasting lines prior to the connection of electric or electronic detonator series; and
  - (4) **Total blasting circuit resistance prior to connection to the power source.**
- (b) **In underground operations—**
  - (1) Continuity of each electric detonator series; and
  - (2) **Continuity of blasting lines prior to the connection of electric or electronic detonators.**

## Notes

### Amendments

[61 FR 36801, July 12, 1996, as amended at 85 FR 2027, Jan. 14, 2020]

### Source

Source: 61 FR 36801, July 12, 1996, unless otherwise noted.

### Authority

Authority: 30 U.S.C. 811.

### Source

Source: 50 FR 4082, Jan. 29, 1985, unless otherwise noted.

### Amendments

[61 FR 36801, July 12, 1996, as amended at 85 FR 2027, Jan. 14, 2020]