The agency first published the request for information (RFI) for 'Exposure of Underground Miners to Diesel Exhaust' in June 2016, allowing for comments through November 30 of that year. The following month, after a collaboration effort at a partnership meeting, the floor was reopened for input and interested parties had until January 9, 2018, to submit comments.
MSHA has received additional requests from stakeholders in the period since the deadline to provide additional time to share data and input regarding the effectiveness of existing standards. As a result, the public now has until March 26, 2019, at midnight Eastern Standard Time (EST) to provide input on the RFI.
The request can be read in its entirety here.