Section 1241 - Minimum Performance Standards for Multiposition Small Engine Exhaust System Fire Ignition Suppression for Engines Manufactured After June 30, 1978The following minimum performance standards for Mse. exhaust systems are established to prevent the ignition of fire in organic fuels consisting of, or developed from forest, brush or grass vegetation.
(a) Carbon Particle Retention or Destruction. Each Mse. exhaust system or a spark arrester used in or with such exhaust system shall be designed to retain or destroy 90% or more of the carbon particles having a major diameter greater than 0.023 in. (0.584 mm) as determined when tested in accordance with the provisions of part 3 of the Society of Automotive Engineers (SAE) Recommended Practice J335(b).(b) Exposed Surface Temperature. The Mse. exhaust system shall be designed so that the exposed surface temperature shall not exceed 550 F (288 C) as determined when tested in accordance with the provisions of part 4 of SAE Recommended Practice J335(b).(c) Exhaust Gas Temperature. The Mse. exhaust system shall be designed so that the exhaust gas temperature shall not exceed 475 F (246 C) as determined when tested in accordance with the provisions of part 5 of SAE Recommended Practice J335(b).(d) Debris Accumulation. The Mse. exhaust system shall be designed in such a manner that there are no pockets or corners where flammable material might accumulate. Pockets are permissible only if it can be substantiated by suitable test that material can be prevented from accumulating in the pockets.(e) Durability. The Mse. exhaust system must be constructed of durable material and so designed that it will, with normal use and maintenance, provide a reasonable service life. Parts designed for easy replacement as a part of routine maintenance shall have a service life of no less than 50 hours. Cleaning of parts shall not be required more frequently than once for each 8 hours of operation.(f) Serviceability. A spark arrester shall be so designed that it may be readily inspected and cleaned.Cal. Code Regs. Tit. 14, § 1241