Simon Plummer, FläktGroup’s national fire safety manager, explains: “Currently, the lack of definitive guidance for auditing mechanical smoke extraction designs in high rise buildings means that their specification is often based on cost rather than verifiable information on their performance. This is because, unlike natural smoke shafts, mechanical systems do not yet appear in the Building Regulations and are instead treated as a fire safety ‘engineered solution’.

“However, if a clear set of technical standards and parameters for mechanically ventilated smoke shafts was included in Approved Document B, the process for specifying and approving their design would be simpler and more transparent.

“Mechanical smoke shafts are fast becoming more popular due to the reduced amount of space required for these systems, so it’s time to demystify their design and selection. A wealth of data is available after decades of common use. By building upon this knowledge, the most suitable solution – not just the cheapest – can be chosen to maximise fire safety in high rise buildings.”