Home networks and the interconnection of home appliances is a classical theme in pervasive computing research. Security is usually addressed through the use of encryption and authentication, but there is a lack of awareness of safety: preventing the computerized house from harming the inhabitants, even in a worst-case scenario where an unauthorized user gains remote control of the facilities. We address this safety issue at the programming language level by restricting the operations that can be performed on devices according to the physical location of the user initiating the request. Operations that pose a potential safety hazard can only be performed within a physical proximity that ensures the safety of the operation. And also study the performance of smart home hardware implementations.