Extra care is necessary after opening a battery compartment, which has been sealed. Because hydrogen is colorless, odorless and tasteless, such compartments should always be thoroughly ventilated before they are entered. To avoid the possibility of an explosion, no light switches should be turned on and no electrical connections should be made or broken in the compartment until it has been well ventilated. When preparing to recharge a battery located in a battery compartment, verify that the ventilating system is operating properly before starting the charge. Stop the charge if the ventilation is interrupted.