The Building & Engineering Services Association (B&ES) has published new, updated editions of two essential industry publications: DW/144: Specification for Sheet Metal Ductwork, a comprehensive reference work recognised as the Standard Specification for ductwork manufacture and installation, and DW/143: Guide to Good Practice – Ductwork Air Leakage Testing, a concise practical guide to leakage testing and ductwork classification.

DW/144 has gained national and international recognition, since its first publication in 1963, as the standard against which the quality of ductwork manufacture and installation should be measured. The newly-released second edition has been aligned to all current BS, BS EN ISO and other standards and regulations and builds on DW/144’s indispensable contents with far-reaching revisions which take account of developments in technology and working practices.

DW/144 defines specifications for sheet metal ductwork for low, medium and high pressure/velocity air systems. The publication’s 200 pages cover ductwork application, materials, classification and air leakage; define the technical information to be provided by system designers to ductwork contractors; and look in detail at rectangular, circular, and flat oval ductwork. Content has been expanded on hangers and supports, smoke and fire dampers, external ductwork, internal duct linings, thermal insulation and air terminal units, many clear reference tables.

DW/143: Guide to Good Practice – Ductwork Air Leakage Testing has also been brought fully up-to-date, with clear explanations of the classes of ductwork that must be tested under regulations, acknowledging the re-introduction of high-pressure Class D ductwork to conform to European practice. Leakage testing of high-pressure ductwork is mandatory in DW/144, with testing of ductwork designed to operate at low and medium pressures not mandatory and required only when stipulated in individual job specifications.

Both DW/144 and DW/143 have been called up in the UK Building Regulations Approved Documents L2A and L2B which deal with the conservation of fuel and power in buildings other than dwellings and which set out the requirements for the testing of ductwork.

For more information or to purchase a copy of DW/144 or DW/143, call B&ES Publications on 01768 860405 or visit www.b-espublications.co.uk