This specification covers limestone suitable for use as dust in coal mines to prevent coal dust explosions. The limestone shall conform to the chemical composition requirements prescribed. The chemical analysis and the particle size analysis of the limestone shall be conducted.

1.1 This specification covers pulverized limestone suitable for use as dust in coal mines to reduce risk of coal dust explosions.

Note 1: Pulverized limestone can serve as a source of incombustible material in coal mine operations. Limestone is dusted onto coal exposures in sufficient amount so that the incombustible content of the combined coal dust, rock dust, other dust, and moisture shall not be less than 80 % of all loose dust (MSHA 30 CFR 75.403). With such a concentration of limestone incombustible material, dust explosions cannot initiate or be propagated from nearby gas explosions. The limestone must be substantially dry in order to dust satisfactorily.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.