Standard Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials (Includes all amendments and changes 3/11/2024).
NORMA vydaná dňa 1.2.2024
Prečo Redline?
Redline predstavuje rýchly a jednoduchý spôsob ako porovnať všetky zmeny medzi aktuálne platnou normou a predchádzajúcou verziou.
Vďaka redline sa okamžite dozviete o:
Ušetrite si čas aj starosti!
Vďaka Redline už nebudete musieť strácať čas zisťovaním, čo sa v novej norme zmenilo. Redline Vám ušetrí čas a zaručí, že sa o zmenách v norme dozviete.
Cena
Ak si zvolíte možnosť "Platná norma + Redline", potom dostanete oba dokumenty! A čo je najlepšie, cena Platné normy + Redline je len o niečo málo vyššia ako cena samostatnej platné normy.
Označenie normy: ASTM C670-24a
Dátum vydania normy: 1.2.2024
Počet strán: 10
Približná hmotnosť: 30 g (0.07 libier)
Krajina: Americká technická norma
Kategória: Technické normy ASTM
This practice provides guidance in preparing precision and bias statements for ASTM test methods pertaining to construction materials. Test method shall conform to the maximum acceptable range of individual measurements. In order to be valid the indexes of precision to be included in the precision statement as guides for the operator must be based on estimates of the precision of the test method obtained from a statistically designed inter-laboratory series of tests. This series of tests must involve a sufficient number of laboratories, materials, and replicate measurements so that the results obtained provide reliable estimates of the true precision characteristic of the test method. The procedures described in this practice are based on the assumption that the proper estimates of precision have already been obtained. In any test method, tolerances are placed on the accuracy of measuring equipment. All tests made with a given set of equipment which has an error within the permitted tolerance will produce results with a small consistent bias, but that bias is not inherent in the test method and is not included in the bias statement for the test method. There are two conditions which permit the bias of a test method to be estimated: a standard reference sample of known value has been tested by the test method, and the test method has been applied to a sample which has been compounded in such a manner that the true value of the property being measured is known, such as may be the case, for example, in a test for cement content of concrete.
Keywords:
acceptable range, bias, coefficient of variation, difference limit, multilaboratory precision, single-operator precision, standard deviation, test determination, test result,, ICS Number Code 91.100.01 (Construction materials)