>This kind of failure (high voltage parts close to low voltage ones, close to liquid damage prone areas, without any underfilling) is documented by Louis Rossma

>This kind of failure (high voltage parts close to low voltage ones, close to liquid damage prone areas, without any underfilling) is documented by Louis Rossmann. It is, however, not always feasible or possible to entirely prevent. Why not feasible or possible? Laptops are not even used in any harsh conditions at all, they die off on the most minuscule water ingress. Take a washing machine - full of electronics with proper power lines and microprocessors - lots and lots of vibration and humidity. While washing machine PCBs tend to be silicone potted for instance, yet conformal coating goes a very long way compared to bare copper and solder joints. Putting high voltage power lines next to lower one is a rookie mistake, every single wall charger has an air gap between primary and secondary (or at least it should) and decent creepage distance. Alternatively they could have added protection devices (e.g. MOVs, diodes) to clamp down the voltages.