In the near future, first responders such as firefighters might be supported by sensor nodes, both installed before the incident and placed by the responders themselves. To communicate with these sensor nodes, the first responders could be equipped with hand held devices, e.g. PDAs with wireless LAN, additionally equipped with a radio module of the same type as used by the sensor nodes. This scenario enables the usage of the PDAs as mobile communication backbone by the sensor nodes, as well as allowing the first responders to access nodes in the sensor network in an efficient way, both near and far. This paper presents a weighted routing protocol for heterogeneous networks, which could be used in such a scenario.