## 5 Related Work  
Emergency situations pose a grave danger to human life and well-being. For this reason, developing technology to support responders in these situations has a high priority. In particular, distributed sensor actuator systems with wireless communication technologies have been researched in various modalities for support of first responders [10]. The cumulative result of this research is the discovery that there is a correlation between the ability of emergency responders to achieve their goal and the level of aid provided by the technical systems supporting them. One approach to evaluating supporting technology is to simulate the emergency situations, the environment, and the response team, and evaluate how certain types of technology would affect the outcome [11]. Here the difficulty is efficiently simulating all parameters, including the interactive human aspects, in such a way as to realistically depict the effect of a novel technological advantage. For example, such simulations have been used to demonstrate the effectiveness of novel communication technologies [12]. In this work opportunistic communication using low-cost 802.15.4 mobile nodes is explored to evacuate individuals safely outside a hazardous zone. The result is that novel robust communication technologies can improve outcomes for emergency situations such as building evacuations, due to the fact that communication is critical for avoiding catastrophic outcomes [12]. While the research previously reviewed is generally applicable for emergency situations and responses, different requirements and goals apply specifically when it comes to the problem of firefighters and related technology. Thus, in the following we restrict our review to publications investigating communication and interaction in frontline firefighting or systems touching especially on the issues described in the previous sections. [PERSON] _et al._[13] present an analysis of firefighter work practices isolating three major activity patterns: rigid structures, independent units and monitoring. The authors report from behaviors that match well with our observations, identifying communications as stressful though essential aspect of the work. [PERSON] [14] identifies the accurate and timely monitoring of and feedback to attacking troop as one of the major goals of a firefighter support system [14]. [PERSON] _et al._[15] conducted an HCI-based investigation with firefighter ICs and found that the automation of routine tasks could yield the biggest improvement of firefighter work. As the frequent sending of status information of a firemen to an IC can be seen as such a routine task, this can be seen as in conformity to our analysis. A well-established tool to support relocation of lost firefighters is the Personal Alert Safety System (PASS) [16]. The PASS monitors the movement of the firefighter and creates a high volume sound signal if no motion is detected after some time (typically in the order of 30 s). Further commercially available systems that focus on (re)localization are the ultrasound-based SummitSafety Pathfinder system [17] and the radio-based Draeger FRS1000 system [18]. Both systems provide a handheld directional tracking device with which a missing firefighter or a beacon can be located. Other researchers have investigated effects of the IDHL on wireless networks. [PERSON] _et al._ studied the performance of various IEEE 802.x wireless technologies under the impact of fire, smoke and vapour [19]. A similar study was conducted by [PERSON] _et al._[20], which additionally investigated the influence of firefighter equipment on radio signals. Opposed to [PERSON] _et al._, they reported no influence on radio reception due to vapour. [PERSON] _et al._[21] investigated the creation of a robust ad-hoc network when the nodes are automatically deployed. They present an algorithm to deploy nodes based on signal strength measurements to ensure a 90% connectivity even if nodes of the consecutive network fail.