Are aircraft unique?
It seems outrageous that detection systems have not been mandated on all public transport aircraft, assuming that suitable technology is available.
However, how can any air conditioning system be totally immune from the probability of finite quantities of lubricant contaminating the supplied air? This cannot be a problem unique to airborne systems supplied by jet-engine compressor bleed-air. The types of lubricants, of course, are another matter, but I would wager that offices and hotels throughout the world must also be susceptible to comparable pollution mechanisms - not to mention trains and buses.