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Understanding BS 476 Part 22: A Comprehensive Guide to Fire Resistance Testing

Fire safety is essential in building design and construction, and passive fire testing is crucial in ensuring safety and compliance with building regulations. Central to this process is BS 476 Part 22 - a standard that outlines procedures for testing the fire resistance of non-loadbearing elements. In this guide, we delve into the specifics of this standard, from its relevance and scope to the practical aspects of the testing procedures and interpretation of results.

A UKTC engineer against a fire furnace.

An Overview of BS 476 Part 22

The Importance of BS 476 Part 22

BS 476 Part 22 is a pivotal element in the broader framework of building safety standards. It provides a comprehensive method for testing the fire resistance of non-loadbearing elements such as doors, shutters, and certain types of ducts and dampers. By adhering to this standard, manufacturers and building professionals ensure that their products can withstand the stringent conditions of a fire, thus contributing to the overall safety of the building and its occupants.

Scope of BS 476 Part 22

BS 476 Part 22 scope describes the procedures for determining the fire resistance of any non-load bearing elements of the building construction when subjected to heating and pressure conditions specified in BS 476 Part20. The test isconducted in line with BS 476 Part20 with regular observations on the behaviour and impact of the specimen material or object; including - but not limited to - the mode of failure in the event of a collapse.

The results are recorded in elapsed time to the nearest completed minute, from the commencement of the heating and pressure being impacted through to the failure of the specimen. The test should be conducted by exposing the building element from both sides; if the testing is carried or conducted on one side, then only one specimen would be taken, and rationale clearly stated in the report.

Understanding the BS 476 Part 22 Testing Procedures

Testing Equipment

The equipment used in the BS 476 Part 22 testing process is designed to simulate the conditions of a real fire. The main component is a furnace capable of reaching the high temperatures of circa 1200 degrees celsius very rapidly. Additionally, temperature-measuring devices ensure that the test conditions meet the specified criteria.

Test Procedures

The general test procedure begins with placing the test specimen in the furnace. The temperature is then raised according to a predetermined time/temperature curve. Throughout the test, observations are made to assess the specimen's integrity and insulation performance.

Criteria for Success

The test's success is based on two main parameters: integrity and insulation. Integrity refers to the specimen's ability to prevent the passage of flames and hot gases, while insulation refers to limiting the rise in temperature on the non-exposed face to below-specified levels. Irradiance is also monitored by means of a radiometer in accordance with BS 476-20.

Interpretation of BS 476 Part 22 Test Results

Understanding Test Report

The test report provides a comprehensive overview of the test. It includes the test's duration, the specimen's performance, and records of any occurrences during the test, such as the appearance of cracks or the emission of flaming particles.

Evaluating Test Results

The test results provide vital information about the fire resistance capabilities of the tested element. A product that meets the criteria for both integrity and insulation is deemed to have passed the test. Failure in either category indicates the product may not provide sufficient fire resistance in a real-life fire scenario.

Role of BS 476 Part 22 in Building Regulations and Safety

BS 476 Part 22 in Building Regulations

The results from BS 476 Part 22 tests are integral to building regulations. They inform the fire safety requirements for different types of buildings and the selection of materials used in construction. Therefore, ensuring compliance with these results is critical to achieving a safe and compliant building. However, there is an ongoing debate within the government as to the removal of BS 476 Part 22 from Approved Document B. Read more here.:

Enhancing Fire Safety with BS 476 Part 22

Adherence to BS 476 Part 22 standards helps improve the fire safety of buildings. It provides assurance that the building's non-loadbearing elements will perform as expected in the event of a fire, thereby protecting life and property.


Understanding and adhering to the BS 476 Part 22 standard is crucial in passive fire testing. This standard not only stipulates the requirements for the fire resistance of non-loadbearing elements but also forms a vital part of building regulations and safety standards. Compliance with BS 476 Part 22 helps to ensure that buildings are as safe as possible, capable of withstanding the intensity of a fire and providing invaluable time for occupants to evacuate safely. It provides an in-depth, robust methodology that underpins fire resistance testing for non-loadbearing elements, thus bolstering building safety and resilience.

How United Kingdom Testing & Certification (UKTC) can help.

United Kingdom Testing and Certification (UKTC) have significant experience classifying non-loadbearing elements such as doors to BS 476 Part 22 at our state-of-the-art fire testing laboratory. We deliver market fire testing and certification services that enable manufacturers of building materials and products to demonstrate compliance with all appropriate international standards, regulatory obligations, and customer expectations. We deliver unparalleled service to our global customer base with industry-leading turnaround times.

Are you looking to find out more information? Contact us or call us on 01355 433122; our experienced team will be happy to help.


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