Recently, I had to go to London for a meeting. Beforehand, I watched the news about the volcano in Iceland to see whether it would affect my trip. To be safe, I took out an insurance policy that covered delays, in case the volcanic ash prevented me from returning home on time.
Fortunately, everything went smoothly and I could have saved the money I spent on insurance.
The BBC reported that the threshold for airlines to fly safely was 0.002 grams of ash concentration per cubic metre of air. Scientists and engineers were convinced that, below the threshold, no damage would be done to the engines. Concentration in British airspace was about 0.0001 grams per cubic metre.
But previously, regulators had taken a zero-tolerance approach to volcanic ash, as set out by the International Civil Aviation Organisation.
The reason for this, according to the BBC report, was that it was previously not possible to detect ash at the very low concentrations that modern equipment is capable of measuring. So the policy was simply to avoid flying.
Theoretically, it could have been business as usual amid such a low concentration of ash - just one-twentieth of the threshold - and the inconvenience to so many passengers could have been significantly reduced.
Regulators, more comfortable with the status quo than risk-taking, might think differently.
As an engineer, I understand the need for a safety margin, or a margin for any foreseeable error. But the issue is whether an excessive margin could do more harm than good to the industry.
If the threshold has wide support, regulators should consider revising the current restrictions. It may be a case of unnecessarily strict rules that are obsolete in the modern age.
Hong Kong's ban on private cars that run on diesel - because their emissions were deemed greater than cars using petrol - is another example. The latest Euro 5-compliant diesel engines emit fewer particulates and one-third less carbon dioxide than petrol units with the same volume. Perhaps it is time for this outdated 1990s legislation to be revised.