Cements - Chemical analysis
NCh 147:2020 Cementos- Análisis químico (NCh 147:2020 Cements - Chemical Analysis); (42 pages, in Spanish)
The notified rule establishes the procedures for determining the chemical components of cements, as indicated and defined in clause 3 of the rule. This rule applies to the cements defined in NCh148 and used in plasters, mortars and concretes. This rule contains descriptions of the reference methods and, in some cases, an alternative method (see Annex A) that can be considered equivalent to the reference methods when it has been approved in advance, in view of the provisions of NCh-ISO/IEC 17025. In the event of a dispute, only the reference methods may be used. In Annex A, there are general guidelines on the alternative method, which uses X-ray fluorescence (XRF) for the determination of silicon oxide (SiO2), aluminium oxide (Al2O3), iron oxide (Fe2O3), calcium oxide (CaO), magnesium oxide (MgO), sulphur trioxide (SO3), potassium oxide (K2O), sodium oxide (Na2O), titanium dioxide (TiO2), phosphorus oxide (P2O5), manganese oxide (Mn2O3), strontium oxide (SrO), chloride (Cl) and bromine (Br). The alternative method can be applied to other relevant cases when appropriate calibration has been carried out. This method is based on the use of fused beads or pressed pellets and on analytical validation through the use of reference materials.
The rule does not concern safety or environmental issues associated with its use, if there are any. It is the responsibility of the user of this rule to establish appropriate health and safety practices, and to determine the degree of application of the regulatory limitations prior to use.