The Hong Kong Apartment Complex Fire

 

In the afternoon of Wednesday, November 26, it was windy in the part of Hong Kong where eight 31-story apartment towers called Wang Fuk Court were undergoing renovations.  As has been the custom for hundreds of years, exterior scaffolding made of bamboo was erected around the towers.  To prevent damage to the single-pane windows of the complex, workers had covered the windows with foam-plastic sheets.  Nylon safety nets surrounded the scaffolding.  What could go wrong?

 

The world found out when an unknown cause started a fire in the lower level of one of the scaffolds.  The flames quickly spread from high winds to the flammable plastic sheets over the windows.  Burning debris and flames spread from tower to tower until seven of the eight towers were engulfed.  About 40% of the residents were over 65, and the fire alarms in many of the buildings were later found to be out of order.

 

For the next day or so, the fire defeated efforts of thousands of firefighters to control it.  As of this writing, the confirmed death toll stands at 146, with dozens more missing.  About 4,600 people lived in the complex, so many got out alive.  But many others, probably including most of those who needed mobility assistance to escape, didn't make it.

 

News reports are calling this tragedy a "man-made disaster," and I couldn't agree more.  Authorities have arrested several officials of the construction company in charge of the renovations, Prestige Construction and Engineering Company, and have halted the firm's work on all other projects in order to conduct safety inspections. 

 

Whoever made the choice of protective window panels may have chosen low cost over safety.  In any event, that choice directly contributed to the fire perhaps more than anything else, although final conclusions will have to await a thorough investigation.  The use of nylon for safety netting and bamboo for scaffolding are also questionable, although China has a centuries-old tradition of bamboo scaffolding that has only recently come into question as metal scaffolding gradually supplants it.  Photos of the scene after the disaster seem to indicate that the scaffolding largely stayed in place, but was charred to the point of being structurally unsound.

 

As soon as I learned of this fire, I thought of the 2017 Grenfell Tower fire in London.  In that disaster, a refrigerator caught fire in a lower apartment and the flames spread to flammable exterior insulating sheathing that had been installed in an upgrade some years before.  The fire propagated behind the sheathing and was difficult to extinguish, and before it was all over, 72 people died and many more were injured.  Again, negligent planning and a failure to take account of the flammability of exterior sheathing was at fault, just as it appears to be in the Wang Fuk Court fire.

 

Engineering ethics requires imagination of a particularly informed type:  imagination bolstered by in-depth technical knowledge.  Engineers sometimes have a reputation for being dour pessimists who always jump to the worst-case scenario of a given situation.  But in the case of the Hong Kong fire, engineers were not pessimistic enough.  Nobody apparently imagined what would happen if one of the plastic window-sheathing panels caught fire, especially if it was on a lower floor of a building that happened to be upwind of most of the others on a blustery day. 

 

It's possible that workers were instructed not to smoke or to engage in operations that might lead to a fire.  That's all very well, but not everybody follows instructions. And even the best-intentioned workers can be using equipment that shorts out or otherwise becomes a source of ignition.  Good safety practitioners imagine that something statistically unlikely will nevertheless go wrong, and then draw conclusions from that premise. 

 

Judging from the number of residents listed and the casualty list, it's possible that about 5% of the listed residents died in the fire.  That means that 95% escaped either with no injuries or non-life-threatening ones, while however losing most of their worldly possessions.  No one I know would like to go through an unplanned experience that will strip you of your things and lead to a one-in-twenty chance of death.  So while fire escapes and other built-in safety features allowed most residents to escape the flames, over a hundred didn't.

 

Major renovation projects are routinely inspected by civil authorities, and I can't imagine that this project was an exception.  If a construction firm neglects to take due safety precautions, it is the civil authority's responsibility to step in and halt work if necessary in order for safety hazards to be addressed.  This obviously wasn't done. 

 

I don't know the nature of safety inspection services in Hong Kong, but among those to be held accountable should be whoever permitted the work to proceed.  Such officials can be subject to corruption pressures, and until a tragedy like this occurs, no light is shed on the fact that corners are being cut by paying off inspectors.  I have no reason to believe that this was the case here, but it is certainly an avenue worth investigating.

 

Disasters like this one can have the silver lining of making future safety regulations and inspections much more rigorous.  As the investigations proceed and the chain of causation is revealed, Hong Kong engineers, construction firms, and officials can all learn valuable lessons that are driven home by the horrible example of what can go wrong if safety measures are neglected.  My sympathy is with those who lost loved ones in the fire.  And my hope is that nobody anywhere in the world puts flammable sheathing on high-rises ever again.

 

Sources:  I referred to a BBC report at https://www.bbc.com/news/articles/cdxe9r7wjgro, a report from the news outlet livemint.com at https://www.livemint.com/news/world/hong-kong-apartment-fire-death-toll-climbs-to-146-probe-reveals-fire-code-violations-11764496767266.html, and the Wikipedia article "Grenfell Tower fire.

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.

Sources:  I referred to news reports about the Grenfell Towers fire carried by the Australian Broadcasting Company on June 17 at http://www.abc.net.au/news/2017-06-17/grenfell-tower-panels-not-suitable-for-tall-buildings/8627790, the Canadian Global News at http://globalnews.ca/news/3536188/grenfell-tower-fire-death-toll/, and the Wikipedia articles "Grenfell Tower fire" and "Triangle Shirtwaist Factory fire."  My blog on the Address Hotel fire in Dubai appeared on Jan. 4, 2016.