The output from the transmissometer is recorded on a strip chart recorder. An induced draft fan blows the generated smoke past the transmissometer an out through the top of the stack. White smoke is generated by vaporizing diesel fuel in a specially designed system . The vapor is diluted with ambient air to form a mist. The mist is conveyed to the fan and out the stack passing the transmissometer.
Black smoke is generated by burning organic hydrocarbons in a specially designed firebox.
Poor combustion is encouraged creating soot. The soot is conveyed to the fan and out the stack passing the transmissometer. Fuel spills are prevented by placing the fuel tanks in a container. The amount of smoke is controled by valves on a console . It runs about 15 seconds.