What is BS EN 16475‑3 about?
BS EN 16475‑3 is part three of a series of European standards on chimney accessories which covers Draught regulators, standstill opening devices and combined secondary air devices.
BS EN 16475‑3 specifies the requirements and test methods for draught regulators, standstill opening devices and combined secondary air devices that are used as components, carrying flue gases, in order to limit the draught in chimneys and provide secondary air to the chimney.
BS EN 16475‑3 also specifies the requirements for marking, manufacturers’ instruction, product information and attestation and verification of constancy of performance (AVCP).
Note: Draught regulators, standstill opening devices and combined secondary air devices for positive pressure chimneys are not covered by this standard.
Who is BS EN 16475‑3 for?
BS EN 16475‑3 on chimneys accessories is relevant to: 
- Chimney manufacturers
- Food industry
Why should you use BS EN 16475‑3?
Draught regulators are used to stabilize and decrease chimney draught in ventilation, flue and smoke ducts. The secondary air system reduces harmful exhaust constituents during the cold start phase. Standstill opening devices interlocked with the combustion system are exclusively for the purpose of ventilating the chimney during standby.
Independent draught regulators are for the purpose of reducing negative pressure that is too large in the chimney, which can result through the use of commercially available cross-section dimensions, despite being designed e.g. according to EN 13384-1:2015, Calculation method for chimneys serving single appliance. They serve to increase the flue gas speed and the ventilation of the chimney, for the purpose of drying out.
BS EN 16475‑3 can help you by providing requirements and test methods for draught regulators, standstill opening devices and combined secondary air devices that are used as components in chimneys. This information can help in making the manufacturing process of chimneys streamlined and thus increase efficiency in the organisation.
