70.220—Status change reports.
(a)
If there is a change in operational status that affects the respirable dust sampling requirements of this part, the operator shall report the change in operational status of the mine, mechanized mining unit, or designated area to the MSHA District Office or to any other MSHA office designated by the District Manager. Status changes shall be reported in writing within 3 working days after the status change has occurred.
(b)
Each specific operational status is defined as follows: (1) Underground mine: (i) Producing —has at least one mechanized mining unit producing material.