sorry sir,

my english is weak. i'm trying to say potting the sparking circuitury near the fuel will protect from triggerring the combustion by isolating the explosive vapour from the circuitury. ciruitury would not put off that much ammount of heat that starts the reaction, it needs very high tempratue, what can trigger the reaction is an spark which has high tempratures in its span. potting is certainly is a solution.

abhishek