1 . 6 . 1 The gravitational system of inch-pound units is usedwhen dealing with inch-pound units。In this system,the pound(lbf)re presents a unit of force(weight)。1 . 6 . 2 It is common practice in the engineering profession toconcurrently use units representing both mass and force unless动态计算(F = Ma) are involved。This implicitlycombines two separate systems within a single standard。Thesetest methods have been written using inch-pound units(gravitational system);however,conversions are given in the SI系统。the use of balances or scales recording pounds of mass(lbm),or the recording of density in LBM/FT3 should not beregarded as non conformance with this standard。1 . 6 . 3 The sieve designation s are identified using The " standard " system in accordance with Specification e 11,such as 25mm and 75 m,followed by the " alternative " system of 1 in。and No. 200,respectively。1.7 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026。1.7.1 For purposes of comparing,a measured or calculatedvalue(s) with specified limits,the measured or calculatedvalue(s)shall be rounded to the nearest decimal or significantdigits in the specified limits。1 . 7 . 2 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as theindustry standard。In addition,they are representative of thesignificant digits that generally should be retained。purpose for the procedures used do not consider material variationobtaining the data,special purpose studies,or any consideration s for the user ' s objectives;and it is common practice toincrease or reduce significant digits or reported data to becommensurate with these consideration s。It is beyond the scopeof this standard to consider significant digits used in analyticalmethods for engineering design。1.8 This standard does not purport to address all of thesafety concerns,if any,associated with its use。It is theresponsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limits
正在翻譯中..
