dangerous electrical equipment used by some passengers
on long flights, pax often sleep, some have sleep apnea so need a CPAP machine for restful sleep, also to prevent loud and legendary snoring, gasping, etc which of course isnt appreciated by nearby pax
some airlines allow approved CPAPs to be used, and to be plugged into an approved powerpoint. If their seat doesnt have one, than an approved battery pack is sometimes allowed. Qantas for example is CPAP friendly and gave me a very cheap seat that had a suitable powerpoint
this is all supposed to ba arranged via the net with the airlines special handling section, once reservations have been made
CPAPs are now more common and cabin crew are usually familiar with them so some adventurous CPAP users set up and use their CPAPs without asking anyone, plugging it into any nearby powerpoint, regardless of whether it was only meant for a lower powered laptop. If no nearby powerpoint their battery pack is used which may be an ordinary lead acid car battery., in a disguising container
there are obviously several dangers, including damage to a planes electrical equipment by a non approved CPAP thats plugged in.some batterys can explode or leak acid
cabin crew should always check whether any CPAP user is mentioned on their pax list as being approved, IMO