Sensor networks are increasingly being deployed, either randomly or manually, for monitoring ofrnphysical environments subjected to different applications such as medical, military, agriculture,rnindustry, transport etc. One of the most important applications of a wireless sensor network isrncritical conditions monitoring. In cases like critical condition monitoring application, it isrnimportant that information can be sensed from the physical environment, where the sensorrnnetwork is deployed, while the emergency state is in progress.rnFor critical conditions such as fire, leaking of toxic gases and explosions, the system must be fastrnenough to respond for foreseen events (targets) with in a fraction of seconds. A great challengernto these networks is to provide a fast, reliable, and fault tolerant channel for events diffusionrneven in the presence of emergency conditions that can lead to node failures and path disruption,rnlike dust, fire etc, to the sink that receives those events.rnThe main aim of this thesis work is to discuss in detail and evaluate the performance of differentrnrouting protocols selected from wireless sensor network (WSN) and mobile ad hoc networkrn(MANET) for critical conditions monitoring applications with the help of important metrics.rnThe result shows that multi-path and multi-speed (MMSPEED) routing protocol has a very goodrnperformance of events delivery with in a short end-to-end delay and high ratio of packet deliveryrnby creating a reliable path for packets reaching to the destination in case of critical conditionsrnmonitoring applications with the limitation of moderate power dissipation when compared tornother routing protocols Performance evaluation of wireless sensor network routing protocols for critical condition monitoringrnapplications