Planning Gateway One - Performance-based designs

As a regulator, HSE must base its advice to LPAs on evidence presented in the planning application. A performance-based design must be supported by a proportionate level of information that can provide comfort to HSE that the fire safety design has been carefully considered from the outset and that the overall level of safety provided achieves the best reasonable outcomes.  It is for the applicant to demonstrate to HSE and the LPA that the fire safety design of the development is robust, to the extent that it affects land use planning matters.

HSE does not expect that complex and costly Computational Fluid Dynamics (CFD) analysis will necessarily be available at the planning stage. However, HSE will highlight the risk that the results of future CFD analysis, used to justify a performance-based design, may not support the fire safety design of the development, as proposed in the planning application. Ultimately, this could have implications for land use planning considerations and result in the need for a new planning application. This will be expressed as supplementary information rather than a concern in the advice to the LPA.

Qualitative Design Review (QDR)

BS7974 advocates a Qualitative Design Review (QDR) process as the basis for considering the basic parameters of a project, in terms of fire safety. When assessing a large and complex development, such as a tall residential building, the evidence in a QDR can demonstrate a reflective and considered approach by the applicant. This will help to build confidence and trust with HSE and decision makers at the planning stage.

The QDR process provides an iterative methodology to gather evidence and consider fire safety design, which involves collaborative working between design professionals such as architects, fire engineers and regulators from the earliest stage of design development. As an iterative process, the QDR is a living document that is continually updated at each design stage, each more detailed than the previous. The information and evidence gathered as part of this process is used to support performance-based designs. It should be a demonstrably robust and challenging process that documents the thought processes that have led to the design presented at the planning stage. A QDR can be submitted as part of a planning application. HSE can participate in a QDR process at the pre-application stage but is unlikely to be able to join discussions at short notice.

It is acknowledged that a QDR at the planning stage will be a work in progress. A QDR at the planning stage should identify site constraints and their impact on the design. It should include a “what if” analysis to demonstrate the resilience and robustness of the overall fire safety design where design decisions have been made that are relevant to land use planning matters. In the context of HSE’s assessment, these are elements that are likely to be influential in explaining the rationale for a performance-based design and demonstrating its effectiveness. HSE will expect a level of detail in the QDR that facilitates consideration of fire safety matters relevant to land use planning matters.

The volume of information provided in a QDR can be extensive. Typically, HSE has 21 calendar days to respond to a consultation request from an LPA and it is often not possible to fully assess a QDR in that timescale. In these circumstances, a helpful approach is to summarise information in a QDR as a standalone document or appended to the fire statement form, providing cross references in the fire statement form to direct HSE to relevant information.