(b) At the accessibility to the maker, to have vehicles equipped with brake expertise and that utilize a common diaphragm, the new results criteria specified in the six(a) and therefore have to be confronted with any solitary leakage-sorts of incapacity when you look at the a common diaphragm may rather become met with the degree of leakages-sort of incapacity determined in the six.7. 6(a) and this use which have solitary leakages-form of failures aside from failures during the a common diaphragm.
(c) At option of the producer, the truck portion of people farming commodity trailer, big hauler trailer, otherwise pulpwood truck may be considered from § of the term as opposed to the criteria out of 6(a).
(a) Regarding a motor vehicle other than a truck-tractor that is equipped with more than two axles, in a fashion that the latest quotient static retardation push/GAWR is not lower than 0.twenty-eight your shaft aside from an excellent steerable side axle; and you can
(b) In the case of a trailer-tractor that is armed with more than a couple axles, in a fashion that the quotient fixed retardation force/GVWR is not lower than 0.14.
6.2 Grade holding. With all vehicle parking brake system used, the auto should are fixed facing uphill and you will facing downhill into a flaccid, dead portland concrete tangible roadway which have an excellent 20-% amounts, one another
six.3.1 The brand new vehicle parking brakes is capable of reaching the minimum overall performance given in both 6.step one otherwise six.dos having people single leaks-variety of incapacity, in virtually any most other brakes, regarding a part designed to contain compressed-air or brake liquid (excluding inability off an element of a braking system chamber homes however, in addition to incapacity of any braking system chamber diaphragm that is part of some other brakes including a great diaphragm that is preferred to the fresh new vehicle parking brake system and any other brake system), if the pressures regarding car’s vehicle parking brake chambers reaches the levels calculated for the 6.3.cuatro.
six.step three.dos A technical function should be provided, just 
after a parking brake application is made out of this new pressures inside the the fresh new car’s vehicle parking brake compartments in the account calculated during the 6.step three.4, and all sky and you will liquid pressures regarding the vehicle’s braking possibilities was up coming bled right down to zero, and you may without needing electrical energy, keeps new vehicle parking braking system software with enough vehicle parking retardation push so you can meet with the lowest efficiency given for the 6.step three.1 and in sometimes 6.1 otherwise six.dos.
6.3.step three To own autos and you can busses, with an initial tank system pressure from a hundred psi and you can, if made to tow an automobile armed with heavens brakes, with a good 50 cubic inches shot tank linked to the likewise have line coupling, no later than simply three mere seconds from the time from actuation from the new vehicle parking brake control, brand new physical function described when you look at the six.step 3.2 are going to be actuated. To own trailers, to your have range 1st pressurized to help you a hundred psi making use of the likewise have range part of the trailer test rig (Contour step one) and you may, if the made to tow an automobile armed with sky brake system, that have a beneficial 50 cubic inches sample reservoir linked to the butt supply range coupling, zero afterwards than three seconds since venting into the environment of your own front side have line coupling is established, this new mechanized form regarded for the six.step three.dos are going to be actuated. So it demands can be came across having vehicles, buses and you may trailers both with and you will with no single leakages-variety of incapacity, in virtually any almost every other brake system, off an associate built to have compressed-air otherwise brake water (similar to the parenthetical words specified when you look at the 6.step three.1).