B&ES TR/19

The BESA TR19 guidelines were introduced in 2005 by updating the old TR/17 guidelines which were in effect from 1998. In 2014, TR19 was updated to reflect changes in European standard BS EN 15780:2011 – Ventilation for buildings – ductwork – cleanliness of ventilation systems.^[3] TR19 was updated to reflect the benchmarks and testing protocols as contained in BS EN 15780.^{[citation needed]} The prime changes in TR19 2005 and 2014 versions are introduction of a CQC, testing protocol and test equipment specification, separation of new duct systems from existing systems and introduction of the RRFSO.^{[citation needed]}