Posted By Tabs I would highlight this as a potential issue in my fire risk assessment, if the stairs are used during evacuation. Chargers can be a source of fire, and having combustibles under stairs is an unhealthy thing if the stairs are an escape route. Ventilation may be another issue depending on the products and the ventilation arrangements.

Posted By Merv Newman Under-stairs storage is a constant niggle. I try to stop it whenever I can. The usuals are combustibles/flammables and cleaning or stationary stores. Even if "non-combustibles" are specified it usually turns into inch/mile practices. And you usually have to climb over/through all the junk to get to what you want. While banging your unprotected head on the stairs. And as for recharging batteries, what was that about "well ventilated/no smoking/no naked lights" ? Merv