However
If the batteries, though inside a fireproof enclosure go off line, there is no starting the APU. Isn't the APU a requirement for ETOPS? Difficult to shrug off the EMER battery system due to merely mitigating risk of onboard fire? FAA quantifies an onboard fire as a one in a billion ? The box is an acknowledgement of an increased risk of fire? No resolution of what caused the battery issue? Though contained, is it not yet a fire? Has FAA altered the language in the rule? To make an exception for "well contained fire"?