Mont. Code Ann. § 61-9-412

(1) Whenever any a motor truck, passenger bus, truck, tractor, trailer, semitrailer, or pole trailer is disabled upon the traveled portion of any highway or the shoulder thereof outside of a highway outside of any municipality at any time when lighted lamps are required on vehicles vehicles, the driver of such that vehicle shall display the following warning devices upon the highway during the time the vehicle is so disabled on the highway except as provided in subsection (2):

(a) A lighted fusee, a lighted red electric lantern, or a portable red emergency reflector shall must be immediately placed at the traffic side of the vehicle in the direction of the nearest approaching traffic.

(b) As soon thereafter as possible after complying with subsection (1)(a), but in any event within the burning period of the fusee (15 minutes), the driver shall place three liquid burning flares (pot torches) torches), or three three lighted lighted red electric lanterns lanterns, or three portable red emergency reflectors on the traveled portion of the highway in the following order:

(i) one approximately 100 feet from the disabled vehicle in the center of the lane occupied by such the vehicle and toward traffic approaching in that lane;

(ii) one approximately 100 feet in the opposite direction from the disabled vehicle and in the center of the traffic lane occupied by such the vehicle;

(iii) one at the traffic side of the disabled vehicle not less than 10 feet rearward or forward thereof in of the vehicle in direction the direction of the nearest approaching traffic. If a lighted red electric lantern or a red portable emergency reflector has been placed at the traffic side of the vehicle in accordance with subsection (1)(b)(i) of (1)(b)(i), this it section, it may be used for this purpose.

(2) Whenever any vehicle referred to in this section is disabled within 500 feet of a curve, hillcrest, or other obstruction to view, the warning signal in that direction shall must be so placed as in order to afford ample warning to other users of the highway but in no case less than 500 feet from the disabled vehicle.

(3) Whenever any vehicle of a type referred to in this section is disabled upon any roadway of a divided highway during the time that lights are required, the appropriate warning devices prescribed in subsections (1) and (5) shall must be placed as follows:

(a) one at a distance of approximately 200 feet from the vehicle, in the center of the lane occupied by the stopped vehicle and in the direction of traffic approaching in that lane;

(b) one at a distance of approximately 100 feet from the vehicle, in the center of the lane occupied by the vehicle and in the direction of traffic approaching in that lane;

(c) one at the traffic side of the vehicle and approximately 10 feet from the vehicle in the direction of the nearest approaching traffic.

(4) Whenever any vehicle of a type referred to in this section is disabled upon the traveled portion of a highway or the shoulder thereof outside of a highway outside of any municipality at any time when the display of fusees, flares, red electric lanterns, or portable red emergency reflectors is not required, the driver of the vehicle shall display two red flags upon the roadway in the lane of traffic occupied by the disabled vehicle, or at a distance of approximately 100 feet in advance of the vehicle, and one at a distance of approximately 100 feet to the rear of the vehicle.

(5) Whenever any motor vehicle used in the transportation of explosives or any cargo tank truck used for the transportation of any flammable liquid or compressed flammable gas, or any motor vehicle using compressed gas as a fuel, is disabled upon any highway of this state at any time or place mentioned in subsection (1) of this section, the driver of such vehicle shall immediately display the following warning devices:

(5) (a) one red electric lantern or portable red emergency reflector placed on Whenever a motor the vehicle roadway at used in the traffic side transportation of explosives, a cargo tank truck used for the vehicle and two red electric lanterns transportation of any flammable liquid or portable red reflectors, one placed approximately 100 feet to the front and one placed approximately compressed flammable gas, or a motor 100 feet to the rear of the disabled vehicle vehicle in the center of the traffic lane occupied by such vehicle; using compressed gas as a fuel is disabled upon any highway of this state at any time or place mentioned in subsection (1), the driver of the vehicle shall immediately display one red electric lantern or portable red emergency reflector placed on the roadway at the traffic side of the vehicle and two red electric lanterns or portable red reflectors, one placed approximately 100 feet to the front and one placed approximately 100 feet to the rear of the disabled vehicle in the center of the traffic lane occupied by the vehicle.

(b) flares, Flares, fusees, or signals produced by flame shall may not be used as warning devices for disabled vehicles of the type mentioned in this subsection (5).

(6) The flares, fusees, red electric lanterns, portable red emergency reflectors and flags to be displayed as required in this section shall must conform with the requirements applicable requirements of 61-9-411 applicable thereto. 61-9-411.

(7) As used in this section, "flammable liquid" means any liquid that has a flash point of 70 degrees Fahrenheit or less as determined by a Tagliabue or equivalent closed cup test device.

Display of warning devices when vehicle disabled – definition