The State of California recently introduced an amendment to Title 8 summarized below:
TITLE 8: Division 1, Chapter 4, Subchapter 14
Petroleum Safety Orders – Drilling and Production
Article 2. Definitions
§6505. Definitions.
The following definitions shall apply in the application of these Orders.
Air Intake Shut-off Valve - A device located between the engine air filter and the intake manifold, designed to shut off the diesel engine’s combustion air in the event engine runaway occurs.
Runaway - A condition affecting diesel engines, where the engine overspeeds out of control, as a result of the introduction of airborne flammable gas or vapor via the air intake causing the engine to accelerate to progressively higher and higher revolutions per minute beyond the normal operating range to a point where the engine becomes damaged due to mechanical failure.
TITLE 8: Division 1, Chapter 4, Subchapter 14
Petroleum Safety Orders – Drilling and Production
Article 6. Fires and Explosions
§6625.1. Diesel Engines Runaway Protection.
(a) In order to prevent diesel engine runaway as defined in Section 6505, no employer shall operate a stationary, vehicular or mobile diesel engine within 50 feet of the open well bore or other source of ignitable gas or vapor, unless the employer complies with subsection (b) through (f).
(d) Where the air is not continuously monitored pursuant to subsection (c), diesel engines shall be operated under at least one of the following conditions:
(1) The diesel engine has an approved automatically actuated air intake shut-off valve that is equipped with a remote control readily accessible from the operator location or the equipment control panel where an operator is present.
(e) The air intake shut-off valve or emergency shut-off device used to comply with this section shall be maintained and tested in accordance with manufacturer’s recommendations.
NOTE: Edited for Air Shut-off Valve
Complete Version: https://www.dir.ca.gov/oshsb/Diesel_Overrun_Devices.html
Canada and much of Europe have requirements for Air Shutoff Valves on any diesel engines working in hazardous environments. The United States federal government requires Emergency Shutdown Valves on all diesel engines operating offshore on oil platforms. Eventually all states will regulate the use of air shut off valves as normal safety equipment on diesel engines.