S7.8.3. Performance requirements. In the case of service brakes of a vehicle equipped with one or more anti-lock braking systems, the service braking system shall continue to operate in the event of a single malfunction of such a system and shall stop the vehicle in accordance with point (a) of S7.8.3 or point (b) of S7.8.3. Braking force unit: a device installed in a braking system that provides the energy necessary to actuate the brakes directly or indirectly via an auxiliary device, the driver`s action being only to modulate the level of energy exerted. S5.2 Parking braking system. Each vehicle shall be equipped with a frictional parking braking system fitted with a purely mechanical lock-keeping device which, under the conditions of S6 during the test in accordance with the procedures laid down in S7, satisfies the requirements of S5.2.1, S5.2.2 and S5.2.2 respectively. S5.2.3 with the system activated — (5) a temporary auxiliary axle attached to a motor vehicle during a period of vehicle weight restrictions to change the weight on another axle if the combined total weight on the temporary axle and the axle to be relieved does not exceed 18,000 pounds and the motor vehicle meets all the braking requirements of this article. Electrically operated service brakes are service brakes that use electrical energy to operate foundation brakes. S6.5.6. Initial brake temperature (IBT).
If the lower limit of the IBT specified for the first stop in a test sequence (with the exception of a parking brake holding test) has not been reached, the brakes shall be heated to the IBT by performing one or more brake actuations from a speed of 50 km/h (31.1 mph) with a deceleration rate not exceeding 3 m/s 2 (9.8 fps 2). Federal Motor Vehicle Safety Standard No. 105, Hydraulic and Electric Braking Systems, specifies the minimum performance requirements for a vehicle`s maintenance and parking braking systems. Originally, the standard applied exclusively to passenger cars equipped with hydraulic braking systems. [1] Over the years, the Agency has published several regulatory actions on FMVSS No. 105. [2] Among other things, on 16 January 1976, the Agency extended the requirements of the standard for service braking and parking to school buses equipped with hydraulic braking systems (41 FR 2391). On 2 January 1981 (FR 46 55), the NHTSA published a definitive rule extending the default number. The requirements of 105 for parking brakes for multi-purpose passenger cars, trucks and buses with a total laden weight of 4,536 kilograms (10,000 pounds) or less. Among other things, the final settlement of 2.
In January 1981, the parking brakes of passenger cars, trucks and multi-purpose buses with a total weight of 4,536 kilograms (10,000 pounds) or less were to keep the vehicle stationary for five minutes on a 30% gradient in the front and rear directions. In response to three requests for reconsideration, the Agency decided to amend the slope requirement for parking brakes on these vehicles from 30% to 20% (FR 46 61887, 21 December 1981). Later, the agency created FMVSS No. 135, which originally applied only to passenger cars. In a final rule of 30 September 1997 (62 FR 51064), NHTSA extended the applicability of FMVSS No. 135 to multi-purpose cars, trucks and buses with a total laden weight (GVWR) of 3,500 kilograms (7,716 pounds) or less. These vehicles were previously regulated under FMVSS No. 105.
NHTSA stated that while the proposed amendments are unlikely to impact the non-use issue, standardizing parking brake limitation requirements for all heavy vehicles can reduce the incidence of misuse by making it easier for drivers of those vehicles to apply the parking brake. In addition, the requirement that all heavy-duty vehicles with hydraulic braking be equipped with parking brakes that meet the slope requirement is expected to reduce the likelihood of parking brake failure on most U.S. roads. For these reasons, the agency said it would benefit from a moderate reduction in collisions, injuries and fatalities by expanding the parking braking requirements of Standard No. 105 on all hydraulic brake vehicles with a total weight of more than 4,536 kilograms (10,000 pounds). (a) each commercial vehicle shall be equipped with sufficient brakes to stop and stop the vehicle or combination of motor vehicles; Each commercial vehicle shall meet the requirements for service, parking and emergency braking systems set out in this section. S6.5.1. Brake control. All performance requirements of the service braking system, including the subsystem requirements of standards S7.7, S7.10 and S7.11, shall be met only by the use of the service braking control. In NPRM, NHTSA also addressed several other issues of Standard No. 105.
NhTSA proposed that the wording be used in the paragraph applying the standard (S3. Application) to take into account the inapplicability of the requirements of the standard to hydraulically braked vehicles with a total laden weight of 3,500 kilograms (7,716 pounds) or less. Previously, these vehicles were subject to standard No. 105. Instead, however, Standard No. 135 now applies. This document amends the Federal Motor Vehicle Safety Standard for Hydraulic and Electric Brake Systems to extend the current minimum performance requirements and related test procedures for parking braking systems to all multi-purpose passenger cars (MONOP), buses and trucks with a total laden weight (GVWR) greater than 10,000 pounds (4,536 kilograms) equipped with hydraulic braking systems or Electrical. Currently, the only vehicles with a total laden weight greater than 10,000 pounds and to which the requirements of the parking brake standard apply are school buses.
The agency concludes that it is in the safety interest to require all minivans, buses and lorries carrying GMOs over £10,000 to have parking brakes that meet the performance requirements currently applicable to heavy school buses. S7.11.4. Performance requirements. The service brakes of a vehicle equipped with one or more brake support units or units of braking force, when such a unit is unusable and without reserve capacity, shall stop the vehicle in accordance with point (a) of S7.11.4 or point (b) of S7.11.4. S7.7.1 Test methods for the requirements of S5.2.1 and S5.2.3. Every motor vehicle, with the exception of a motorcycle, when travelling on a motorway, shall be equipped with brakes capable of controlling, stopping, stopping and stopping the movement of that vehicle, including two separate brake application devices, each of which shall be effective in applying the brakes on at least two wheels. If these two separate brake controls are connected in any way, they shall be such that the motor vehicle does not break down without brakes on at least two wheels. (f) modify the service braking system so that it causes only one failure.
In the case of a hydraulic system, it can be a single rupture or leak error, with the exception of a structural failure of a housing common to two or more subsystems. In a vehicle where the brake signal is electrically transmitted between the brake pedal and some or all of the foundation brakes, this may be a single failure in a circuit that transmits the brake signal electrically, regardless of the type of operation of the foundation brakes. For an electric vehicle with RBS that is part of the service braking system, it may be a single defect in the RBS. (f) An electric vehicle equipped with an RBS that is part of the service braking system shall meet the performance requirements over the entire normal operating range of the RBS. In explaining the need for the safety rule, the agency expressed its belief that parking brakes are an important component of operational safety and provisionally concluded that it is in the safety interest to require all vehicles to be equipped with parking brakes that meet federal requirements. When properly lit, parking brakes can prevent driverless roll events that can lead to collisions, injuries and deaths. A review of the agency`s Fatal Accident Reporting System (FARS) database revealed that between 1991 and 1999, a total of three to five fatal vehicle rollover operations occurred with large non-school vehicles with hydraulic brakes. In addition, there were approximately 574 accidents per year during the same period, including 82 injuries due to heavy truck turnover, according to General System of Estimates (GHG) data. GHG data are not sufficiently detailed to determine which of the vehicles were hydraulically braked and which were braked with air, and the data could not be used to determine whether the vehicles were parked prior to the roll incident.
Therefore, these figures likely represented the upper limit of the number of accidents and injuries caused by the roll of parked heavy trucks and buses equipped with hydraulic brakes due to parking braking problems.