This standard BS 2742:2009 Use of the Ringelmann and miniature smoke charts is classified in these ICS categories:
91.060.40 Chimneys, shafts, ducts
13.040.40 Stationary source emissions
This British Standard provides guidance on the use of BS Ringelmann charts to assess smoke emissions from unregulated processes. It is not suitable for calibrating Continuous Emissions Monitoring Systems. It is not applicable to processes whose emissions are regulated by EU Directives with stated Uncertainty.
NOTE Most regulated processes have particulate emissions limits below Ringelmann 1.
This British Standard is intended for use with the related publications:
BS 2742C, Ringelmann chart;
BS 2742M, Miniature smoke chart.
Other measuring devices or charts are not suitable for use with this British Standard.