Opinion | Behavioural design for safer public spaces4 min read . Updated: 24 Sep 2018, 09:14 PM IST
It could go a long way towards designing safer buildings, machines and systems, reducing human errors
Recently, it was reported that a Jet Airways 9W 697 Mumbai-Jaipur flight was routed back to Mumbai after take-off as, during the climb, the crew forgot to select the bleed switch to maintain cabin pressure. This resulted in the oxygen masks dropping. Thirty out of 166 passengers experienced nose and ear bleeding; some also complained of headaches.
Aviation safety experts said such an incident was “extremely rare" as turning on the bleed switch is part of a mandatory checklist for pilots. If turning on a switch that regulates cabin pressure is part of the standard protocol, how could the pilots make such a simple, commonsensical error? And more importantly, how can such errors be avoided in the future?
Traditional thinking suggests increasing better training of the pilots so that it makes them less prone to committing errors. But training is not a foolproof method of ensuring human errors don’t get repeated. That’s because as long as humans need to rely on their memory to ensure something as fundamental as turning on the cabin pressure switch, errors are bound to happen. Sure, checklists work. But that’s still a manual method of ensuring that the switch is turned on. And after repeatedly performing the tasks on the checklists over multiple flights, checklists themselves become routine, habitual tasks done without much thinking. Also, given that there are multiple tasks pilots need to perform in the 3-4 minutes after taking off, the chances of errors happening during those critical moments increase.
So, instead of the pilot having to rely on their memory or routine checklists, the answer to avoid such human errors lies in implementing simple behavioural design nudges. For example, if there was a continuous audio-visual reminder that the bleed switch had not been turned on, it would have drawn the pilot’s attention and it would be much likelier that they would have turned it on. Such an audio-visual reminder was not present in this kind of an older generation aircraft, thus amplifying the chance for human errors .
The Japanese have a term for such error-proofing—poka yoke. This Japanese word means mistake-proofing of equipment or processes to make them safe and reliable. These are simple yet effective behavioural design features that make it almost impossible for errors to occur. The aim of error-proofing is to remove the need for people to think about the products or processes they are using. Some examples of behaviourally-designed products used in everyday life are the washing machines that start only when the door is shut and remain shut till the cycle is over. Elevator doors now have sensors that cause them to not close when there is an obstruction. This prevents injury to the people trying to enter as the doors are closing.
Humans cannot be trusted to be as precise as machines. In fact, human behaviour is far from perfect. Yes, the people who operate expensive and complicated machinery may be the best trained, but human errors in the form of simple error, lapse of judgment, or failure to exercise due diligence are inevitable. According to Boeing, in the early days of flight, approximately 80% of accidents were caused by the machine and 20% were caused by human error. Today, that statistic has reversed. Approximately 80% of flight accidents are due to human error (pilots, air traffic controllers, mechanics etc.) and 20% are due to machine (equipment) failures. That’s why behavioural design needs to be relied upon more than human judgment.
Another instance of how systems could be made safe by applying behavioural design is of flight emergency evacuations. During the emergency landing of the Emirates flight EK521 at the Dubai airport in 2016, passengers ran to get their bags from the overhead cabins instead of evacuating the plane. Only when the cabin crew yelled at them to leave their bags and run did the passengers finally pay heed to their calls and evacuate. Just a few minutes after the evacuation, the plane caught fire. Had even a few passengers waited to get their bags from the overhead cabins, many of them would have gotten engulfed in the fire. Again, the natural instinct to correct such a situation would be to train people to evacuate and get them to listen to the flight’s safety instructions. But behavioural science studies have proven that such efforts are time-consuming, unscalable and most importantly, ineffective at changing human behaviour. In such an emergency situation, if the overhead cabins were automatically locked, with a label “Locked due to emergency", passengers would not waste time trying to open them. That would in turn get passengers to behave in the desired manner and evacuate faster.
Sometimes, behavioural design nudges are intuitive. Other times, they are counter-intuitive. In a fire-drill experiment by behavioural scientist Daniel Pink, he found that placing an obstacle-like pillar in the middle of a doorway got people to exit a hall 18% faster than without the pillar. The pillar was an obstacle, but it split up people into two streams at the exit. That got people to use each side of the door, which in turn made the flow of people exiting the hall a lot smoother and faster. When the pillar wasn’t there to separate them at the exit, people bottle-necked at the door making the exit slower. Likewise, behavioural design could go a long way towards designing safer buildings, machines and systems, reducing human errors.
Anand Damani is a partner at Briefcase Communication and Behavioural Design Consultancy. Comments are welcome at firstname.lastname@example.org.