[Code of Federal Regulations]
[Title 30, Volume 1]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 30CFR23.14]

[Page 139-140]
 
                       TITLE 30--MINERAL RESOURCES
 
  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
 
PART 23--TELEPHONES AND SIGNALING DEVICES--Table of Contents
 
Sec. 23.14  Instructions for handling future changes in design.

    All approvals are granted with the understanding that the 
manufacturer will make his device according to the drawings that he has 
submitted to MSHA and that have been considered and included in the 
approval. Therefore, before making any changes in the design he shall 
obtain MSHA's authorization of the change. The procedure is as follows:
    (a) The manufacturer shall write to Approval and Certification 
Center, Box

[[Page 140]]

201B, Industrial Park Road, Dallas Pike, Triadelphia, W. Va. 26059 
requesting an extension of his original approval and stating the change 
or changes desired. With this request, he should submit a revised 
drawing or drawings showing the changes in detail, together with one of 
each of the parts affected.
    (b) MSHA will consider the application and inspect the drawings and 
parts to determine whether it will be necessary to make any tests.
    (c) If no tests are necessary, and the change meets the 
requirements, the applicant will be officially advised by MSHA that his 
original approval has been extended to include the change.
    (d) If tests are judged necessary, the applicant will be advised of 
the material that will be required. In this case extension of approval 
will be granted upon satisfactory completion of the tests and full 
compliance with the requirements.

[Sched. 9B, 4 FR 1555, Apr. 11, 1939, as amended by Supp. 1, 20 FR 2975, 
May 4, 1955; 43 FR 12315, Mar. 24, 1978; 52 FR 17514, May 8, 1987]