BSRIA first UKAS-accredited provider for BTS 4/2024

Author: Joe Peck

BSRIA, a consultancy and testing organisation, has become the first organisation to receive UKAS accreditation in accordance with BTS 4/2024 for airtightness testing of Raised Access Plenum Floors (RAPFs), following a successful ISO 17025 audit earlier in 2024.

The accreditation formally extends BSRIA’s scope of approved activities and introduces an industry-recognised methodology for testing RAPFs, which play a key role in airflow management in data centres.

Chris Knights, BSRIA Building Performance Evaluation Business Manager and lead author of BTS 4/2024, comments, “The UKAS accreditation ensures we continue to provide independent testing to the highest standards of quality, repeatability, and traceability.

“This is a significant advancement, enabling the industry to adopt a dedicated standard that supports higher-performing building services for owners and operators.”

BTS 4/2024 standard

The accreditation follows the introduction of BTS 4/2024 Airtightness Testing of Raised Access Plenum Floors, which sets out a methodology for measuring RAPF air leakage.

The standard is designed to support efficient airflow management by ensuring conditioned air in underfloor voids is directed to the intended occupied areas rather than escaping through cavities, risers, stairwells, or other adjacent spaces.

RAPFs are widely used in modern construction, particularly in data centres, where optimised airflow is important for both cooling performance and energy efficiency.

BTS 4/2024 supersedes previous guidance, BG 65/2016 Floor Plenum Airtightness – Guidance and Testing Methodology, and incorporates clearer guidance and refined testing processes developed in response to industry feedback.

Chris continues, “An effectively constructed and sealed raised access plenum floor is essential for achieving the air distribution performance intended during the design phase.

“The methodology in BTS 4/2024 provides clear criteria and a step-by-step process for verifying as-built performance.

“With increasing demand for high-performing environments such as data centres, specifying BTS 4/2024 supports effective air distribution and helps ensure RAPFs deliver on design intent.”