Fire safety has been a crucial area of focus in the building design and construction sectors. The necessity to accurately assess the performance of building materials, interior finishes and structures under fire conditions is paramount. In the 20th century, strides were made in the field of fire testing, resulting in the development of standard test procedures that have since shaped modern approaches to fire testing.
In this article, we will delve into the evolution of fire-testing protocols, highlighting the contributions made by key individuals in the 20th century and appreciating the impact made by their work towards establishing fire-testing standards in the present day. A look through this evolution allows one to appreciate how far the fire-testing sector has come and how much more there is to do with the constant pursuit of improved fire safety.
20th-century fire-testing pioneers
To comprehend the advancements made in this field, it is vital to consider the historical context that necessitated the introduction of standardised fire-safety procedures. In the early 20th century, fire occurrences and their destructive consequences were widespread, highlighting the urgent need for comprehensive fire-testing methods.
During the 20th century, Harold R. Thomas, a research engineer at the National Bureau of Standards (now NIST), made noteworthy contributions to fire testing. One of his seminal achievements was the development of ASTM E84, the Standard Test Method for Surface Burning Characteristics of Building Materials. Introduced in 1950, this test became a fundamental tool for evaluating the flame spread and smoke development of materials used in building construction. Thomas’s groundbreaking work provided a foundation for understanding the surface burning behaviour of various building materials and played a pivotal role in establishing fire safety standards.
Another significant contributor to fire-testing standards in the 20th century was Underwriters Laboratories (UL), a renowned global safety certification company. In 1972, UL introduced UL 94, the Standard for Safety of Flammability of Plastic Materials for Parts in Devices and Appliances. This standard, influenced by the work of Dr Harry P. Lundgren and his team at UL, aimed to assess the flammability characteristics of plastic materials commonly used in consumer products. The introduction of UL 94 led to improved safety standards for various plastic components, reducing the risk of fire incidents.
Dr Field and Dr Harris also significantly influenced the development of fire testing. Dr Field’s groundbreaking work on fire-resistance testing, particularly his development of the ‘Fire-Resistance Furnace’, laid the foundation for subsequent advancements. On the other hand, Dr Harris contributed to understanding fire behaviour through his research on flame spread and heat release.
Modern-day fire testing standards
The ‘Fire-Resistance Furnace’ invention allowed for controlled and repeatable experiments, enabling researchers to evaluate the fire-resistance properties of materials with greater precision.
The contributions of Dr Field and Dr Harris, alongside the collaborative efforts of organisations and standardisation bodies such as the American Society for Testing and Materials (ASTM) and Underwriters Laboratories (UL), have resulted in the development of comprehensive fire-safety standards.
ISO 5660 and the Cone Calorimeter Test
The modern era saw significant advancements in fire-testing standards, leading to the development of more comprehensive approaches. In 1993, the International Organisation for Standardisation (ISO) introduced ISO 5660, which revolutionised fire testing with the Cone Calorimeter Test. This test method enabled precise measurement of critical fire parameters, including heat release rate, smoke production and mass loss rate. The Cone Calorimeter Test provided researchers and engineers with valuable data for understanding material behaviour under fire conditions, allowing for better-informed decisions in building design and fire-safety measures.
Evaluating non-combustibility and high-temperature resistance: EN 1182, ASTM E2652 and ASTM E136
Non-combustibility testing is crucial for assessing the fire-resistance properties of building materials. Standards such as EN 1182 and ASTM E2652 provide methods for determining the non-combustibility of materials. While EN 1182 was developed by the European Committee for Standardisation (CEN), ASTM E2652 was formulated by the ASTM. Despite their regional distinctions, both standards share a common aim of evaluating the fire performance of materials. By comparing the scope, testing methods and specific requirements of these standards, we gain valuable insights into the similarities and differences between European and American approaches to fire testing.
ASTM E136 is a widely recognised standard for evaluating materials’ non-combustibility and high-temperature resistance. This standard involves subjecting a material to a vertical tube furnace at a temperature of 750°C (1382°F). ASTM E136 provides valuable data on a material’s fire performance by assessing flame propagation and disintegration parameters. The significance of this standard lies in its ability to determine whether a material is suitable for use in high-temperature environments, such as building facades and fire barriers.
Assessing ignition temperature: ASTM D1929
Understanding the ignition temperature of materials, particularly plastics, is crucial for assessing fire hazards. The ASTM D1929 is a prominent standard that addresses the determination of the ignition temperature of plastics. It provides guidelines for determining the self-ignition and flash temperatures of plastics. The standard outlines testing procedures that allow researchers and engineers to accurately evaluate the ignition temperature of plastics, facilitating the development of fire-safe materials and informing fire-protection strategies.
Flooring fire testing: EN ISO 9239-1
EN ISO 9239-1 is an internationally recognised standard that evaluates the burning behaviour of floorings exposed to a radiant heat source. This standard involves subjecting a flooring specimen to a defined radiant heat flux and measuring various parameters, including flame spread and heat release. By assessing a flooring material’s ability to resist fire spread, EN ISO 9239-1 provides valuable insights into its contribution to the overall fire hazard. This standard’s incorporation into building regulations underscores its significance in promoting fire-safe construction practices.
Upholstered furniture fire testing: EN 1021-1/2
Furniture is a common contributor to fire spreading within buildings. EN 1021-1/2 is a European standard that provides a method for assessing the fire performance of upholstered furniture. The testing procedures outlined in EN 1021-1/2 involve subjecting furniture components to a smouldering cigarette and an open-flame ignition source. By evaluating parameters such as ignition time, heat release and flame spread, this standard helps ensure the fire safety of upholstered furniture, minimising the risk of fire incidents and facilitating compliance with fire-safety regulations.
NIST and Fire Dynamics Simulator (FDS)
The National Institute of Standards and Technology (NIST) has been the forefront of modern fire-testing research. Dr Thomas G. Cleary, a leading expert at NIST, contributed significantly to developing the Fire Dynamics Simulator (FDS), a computational fluid dynamics (CFD) model used to simulate fire behaviour. FDS enables engineers and researchers to predict fire growth, smoke movement and heat transfer in complex building structures, providing valuable insights for fire safety design and analysis.
Professors Vytenis Babrauskas and T. Richard Hull have contributed substantially to fire-testing research and standards. Their expertise in fire behaviour, heat-release-rate measurement and fire modelling have been instrumental in advancing the understanding of fire dynamics and developing more comprehensive fire-testing methodologies.
National Fire Protection Association (NFPA) and NFPA 285
The NFPA plays a vital role in fire-safety standards. NFPA 285, developed in collaboration with experts such as Dr Thomas G. Cleary, addresses the fire propagation characteristics of exterior wall assemblies. It evaluates the interaction between various building components and the potential for fire spread on the exterior facade.
Foundations to modern advancements
The journey from the past’s rudimentary fire-testing methods to the present’s sophisticated techniques has been transformative. The fire-testing standards developed provide a framework for evaluating the fire-resistance properties of materials, promoting consistency and enhancing building safety.
By comparing the 20th-century approaches to modern advancements in fire testing, we can appreciate the strides made in ensuring the effectiveness of fire-protection strategies and ultimately enhancing occupant safety. The continuous efforts to refine testing methodologies and develop new standards have resulted in more accurate assessments of materials’ fire behaviour, leading to improved fire-safety practices in the construction industry. Researchers, engineers and policymakers must stay abreast of these advancements and actively implement the latest fire-testing standards to create safer built environments.
Modern standards focus on quantifiable measurements of critical fire parameters. Heat release rate, smoke production, toxic gas emissions, flame spread and other factors are rigorously assessed, providing a more detailed understanding of material behaviour during fires. These comprehensive metrics enable researchers, engineers and policymakers to make informed decisions regarding building materials, evacuation plans and fire-suppression systems.
Evolution towards saving lives, property and the environment for a safer tomorrow
The evolution of fire-testing standards from the 20th century to the present reflects a continuous quest for enhanced fire safety and building performance. Notable individuals, including Harold R. Thomas, Dr Harry P. Lundgren, Professors Vytenis Babrauskas and T. Richard Hull, and Dr Thomas G. Cleary, have shaped fire-testing standards. While the 20th-century standards laid the foundation, modern approaches offer more comprehensive evaluations by considering a broader range of fire parameters and simulating realistic fire scenarios. These advancements contribute to improved fire-safety practices and aid in designing and constructing buildings that can better withstand fire incidents, protecting occupants and property.
