225 ILCS 705/19.02

In mines sunk after July 1, 1911, the first escapement shaft shall be separated from the main shaft by such extent of natural strata as may be agreed upon by the State Mine Inspector of the district and the owner of the property, but the distance between the main shaft and the escapement shaft shall not be less than 500 feet nor more than 2,000 feet; except that in mines employing 10 men or less the distance between the hoisting shaft and the escapement shaft shall not be less than 250 feet.