Your landlord must ensure that all appliances, electrical products and the like (including fireplaces) be inspected, cleaned and repaired prior to every new lease/tenancy.  This is because you need to be protected from someone else's harms and the landlord needs to ensure that the right individuals pay for damages if they caused them (think prior tenants).  This does not mean that you don't have any responsibility, however. You need to ensure just like everything else that items are turned off, hazards are minimized. If you clean your oven, you clean what you can of a fireplace. The idea is to mitigate your damages.