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“There is a Need to Ensure that the Performance Prescribed is Delivered”

By: HEMANT KHADSE, East Corp, Fire and Life Safety Consultant

Building fire safety relies on three key pillars: material, design, and technology. However, codes and standards serve as the connecting link between these three pillars. Building code compliance must receive adequate consideration during the design phase from architects and planners. Life safety must not be compromised, particularly at a time when building materials and technology are changing so rapidly. The goals of facility owners should not be technology at the expense of safety.

ACTIVE AND PASSIVE FIRE PROTECTION MEASURES

It is most commonly seen as active fire safety as only fire safety measures for the built environment. However, passive fire safety measures are also an equally critical component of life safety. Architectural details in the design of tall buildings play a significant role in the fire safety of the building. In the past, many cases like Grenfell Tower in 2017 became
a disaster largely because of poor passive fire measures.

GRENFELL TOWER FIRE, LONDON

In the case of Grenfell Tower, the disaster was because of the wrong material selection and detailing on the façade cladding. The panels were preferred aluminium instead of zinc panels, which had a more resistant insulation core in a honeycomb shape, only because of economic benefits. Additionally, the cladding system preferred was installed with detail to hide fixings. The system was tested in 2005 for the first time and failed. Tests were reapplied in 2011, 2014 and 2015, and eventually failed every time and classified E. The lowest fire resistance of the European classification is F.

However, the same façade material and system had another installation with detail, without hiding fixings and passed the tests rather successfully with classification C.

The fire code applied in the UK requires to use of materials in the quality of European Class B for buildings taller than 18 meters, and in the quality of European Class C for shorter buildings.

Besides, the material chosen to fill around the new windows was combustible, whereas the code strictly specified the use of rockwool material as it is non-combustible.

TVCC (TELEVISION CULTURAL CENTER) FIRE, BEIJING

The fire in TVCC (Television Cultural Centre) on 9th February 2009 was similar to that in Grenfell Tower in terms of the exterior cladding material. The tower had 32 stories and a height of 159 meters. A high atrium existed between floors numbered 5th and 26th and was in use as a hotel and restaurant. The tower had a rectangular shape in plan and two facades with metal cladding and strips, and two other facades with only glass covering.

As the fire started because of fireworks flames landed on the roof, melted the metal panels, which were titanium-zinc alloy, and walked through the insulation layer inside the panels, which was Extruded Polystyrene (XPS) foam. Mainly because of such façade material, the fire was able to spread all over the building in nearly 20 minutes. The building was not completed by then, so through the window openings, the smoke, and heat moved inside the building. The atrium made a stack effect, making it easier to move upwards and downwards inside. One firefighter died and seven workers were injured in this case.

To ensure fire safety, when a code or a technical regulation prescribes a specific product or a feature, there is a need to ensure that the performance prescribed is delivered. A stringent certification program will ensure reliable assurance between specifiers, buyers, and sellers when implemented correctly. Certification and Listing offer traceability between what is manufactured and delivered at the construction site, linked to what has been tested in an accredited laboratory.

This way façade assembly components when followed by a stringent method of certification, it assures that the manufactured product that carries the certification marking or labels meets the same specified requirements as the product tested.

THE CERTIFICATION PROGRAMS

International Standards ISO 17065 and ISO 17067 give the requirements of how certification programs can be designed, implemented and audited.

The certification programs get audited by Accreditation Bodies, and they establish trust by consistently being able to provide proof of compliance.

Now a few third-party laboratories offer certification of products tested to the following Indian standards:

• IS 16947 Fire resistance tests for doors with glass panes, openable glass windows and sliding glass doors)
• IS/ ISO 834-4: Fire-Resistance Tests Elements: Load Bearing Vertical Separating Elements
• IS/ ISO 834-5: Fire-Resistance Tests Elements: Load Bearing Horizontal Separating Elements
• IS/ ISO 834-8: Fire-Resistance Tests – Elements: Non-load Bearing Vertical Separating Elements
• IS/ ISO 834-9: Fire-Resistance Tests – Elements: Non-load Bearing Ceiling Elements
• IS 16945: Fire Resistance Test for Glass Walls

Several Certification and Listing programs are now drivers for building fire safety for products such as façades in India.

Façade systems can play a very important role in fire safety. The trend is now reversed from Identifying combustible vs. non-combustible façade materials. Owners are now considering performance as a system (panel, framing, firestop, fixing mechanism) material, intermediate and system-level performance. At times it is very difficult to ascribe ‘fire rating’ for certain systems however failure mechanism depends on the fixing mechanism.