Engineering Ethics Blog: The Grenfell Tower Tragedy


In 1974, a new high-rise public housing apartment
building opened in West London. 
Called Grenfell Tower, it was 24 stories tall and designed to house as
many as 600 people in 120 apartments. 
Photographs of it taken before a renovation in 2015 show large windows
on one side and smaller ones on the adjacent side. 

In 2014, as reported in this blog, the 63-story
Address Hotel in Dubai, United Arab Emirates went up in flames as aluminum-clad
foam-plastic panels called architectural cladding or sandwich cladding on its
exterior caught fire and quickly spread the conflagration to most of the outside
of the building.  Amazingly, no one
died in that fire, due to a quick evacuation order by the authorities and the
failure of the fire to spread to the interior of the hotel rooms.  But this was only one of numerous
exterior-cladding fires that have resulted from the use of flammable
architectural materials on buildings that are too tall to be reached
conveniently by fire ladders.

In 2015, the Kensington and Chelsea Tenant Management
Organization, the bureaucracy in charge of public housing in the Grenfell Tower
district, decided to do a renovation, possibly to improve the structure’s
insulation and lower heating costs. 
New windows were installed, thermal insulation was added, and to cover
these changes, sandwich cladding panels were installed to cover the four
exterior side walls. 

Some, perhaps most, of the cladding was made by the U.
S. firm Arconic, which sells various types with different kinds of plastic
between the outer aluminum sheets. 
A cheaper type uses polyethylene plastic, but is not recommended for
structures over 10 meters (33 feet) tall. 
A slightly more expensive type is fire-resistant, as was the thermal
insulation used underneath the cladding. 
But even fire-resistant plastic can burn under some conditions.

When constructed, the building had no sprinkler
system, but the apartments were piped for gas cooking and gas lines were
present throughout the building. 
Each apartment had fire detectors, but a residents’ organization called
the Grenfell Action Group has voiced complaints to authorities over the past
few years about outmoded and non-functional fire extinguishers, flammable
clutter in hallways, and other fire-safety issues, with little apparent
response.

Residents of the Grenfell Towers, as were most other
residents of London, had been instructed in case of fire to remain in place to
be rescued by firefighters, rather than attempt an escape on their own.

In retrospect, the Grenfell Towers fire was a disaster
waiting to happen:  an aging,
open-style building without a sprinkler system but full of gas lines, covered
with apparently flammable sandwich cladding outside potentially flammable
insulation material, crowded with up to 600 residents who had been told to stay
in their apartments in case of a fire. 
And in the early morning hours of June 14, 2017, a fire broke out, reportedly
in a kitchen on the fourth floor.

No sprinkler system or fire extinguisher succeeded in
stopping the blaze before it ignited the exterior cladding, which in a matter
of a few minutes spread the flames upward and eventually completely around the
structure.  Many survivors got out
by disobeying the orders to stay in place.  As of this writing (June 18), the estimated death toll is
58, and is expected to go higher. 
If this is confirmed, it will be the largest number of people to die in
a single fire in London since the Blitz of World War II.

Fires that kill lots of people at once are not that
uncommon, but usually they happen in crowded single-room venues such as
nightclubs where fireworks or other sources of ignition catch flammable
materials on fire.  The spectacle
of an entire high-rise building going up in flames because of flammable
exterior cladding is something that is not supposed to happen in modern
“fireproof” structures. 
But the invention of a cladding material that is light, inexpensive compared
to concrete, solid steel, or aluminum, and reasonably durable has led to its
use and abuse throughout the world. 
And as numerous cladding fires have shown, you can take the most
fireproof building in the world and surround it with thin, flammable sheets
exposed to a lot of air, and what you get is a giant Roman candle waiting to be
set off. 

The Grenfell Towers fire may become a turning point in
the politics and regulations of exterior cladding, similar to the infamous
Triangle Shirtwaist Factory fire in New York City that killed 146 garment
workers in 1911.  Like many of the
residents of the public-housing Grenfell Towers, most of those who died in the
1911 fire were poor immigrants, though they died on the job amid flammable
clothing materials, not at home surrounded by flammable architectural
panels.  The Triangle fire had the
good result of inspiring calls for improved fire-safety building codes and
regulations, which if implemented can prevent tragedies like this.

British Prime Minister Theresa May, already in a
politically weak position, has been jeered and attacked for what many saw as
her inadequate response to the tragedy. 
She and other politicians could turn this situation to the benefit of
their country by leading a thorough investigation into the causes of both the
Grenfell Towers fire and other similar fires in which flammable exterior
cladding has played a role.  Then,
they could take vigorous and definite action with regard to both existing and
future architectural cladding that has any significant chance of short-circuiting
fire safety by enabling the spread of a fire on an otherwise fireproof
structure’s exterior. 

It is ironic that after making people suffer for
centuries the hazards of living in wooden structures that were chronically
prone to burn down, nineteenth-century architects thought they had solved the
problem of fire with concrete-and-steel structures, only to torch their
triumphs in the last few decades by using what amounts to cheap window-dressing
materials that burn like fireworks. 
If I were an architect, I would be afraid to show my face in London
after the Grenfell Towers tragedy. 

The most basic ethical requirement of a profession is
that the professionals look out for the interests of those average citizens
affected by their professional activities, citizens who have no way of knowing what
hazards they could be subject to and how to avoid them.  I would be surprised if more than a few
residents of Grenfell Towers knew anything about sandwich cladding, or the fact
that under the right circumstances it would burn.  Well, everyone knows now.  And I can only hope that this knowledge gets applied to
similar dangerous situations, and we do whatever it takes to keep another
Grenfell Towers fire from happening anywhere, ever again.



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