Características de los servicios de urgencias en los hospitales

The 2003 HSE (2003b) study concluded that the number one situation where accidents occur in the construction site is during the movement of workers within the site. There could have been further conditions that lead to these accidents such as falling from heights or tripping over materials, which was not cited in the HSE report. Nevertheless, it is pertinent to this study to note that movement of workers within the construction site can lead to accidents. This study considers if knowing the location of workers within the construction site can enable the superintendent in making safety decisions.

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The same HSE (2003b) report also cited poor supervision as one of the reasons for accidents occurring on the construction site. Research presented earlier indicates that one of the duties of superintendent is to physically monitor the work occurring on the construction site. It may be concluded that it would be difficult if not impossible for the superintendent to monitor all workers at a given time on the construction site. Therefore any means that can allow the superintendent to know the location of workers within the construction site can be beneficial. Use cases of tracking construction workers within the site, from a safety perspective have been found in the construction industry news. The Ekahau (2009) company demonstrated the use of wireless tags and readers combination to track workers in the construction of tunnels in Spain. Similarly, Northern Light Technologies implemented the use of active and passive RFID tags in the construction of a 4.8km tunnel in Brisbane, Australia (Friedlos, 2008). DPR Construction Company used passive RFID tags and readers at key locations to track the movement of workers, to automate the head count process at a 900,000 SqFt construction site in California (Abaffy, 2013). In the case of DPR construction, they used a vendor who was also able to integrate the tag information into the project building information model. Grunley Construction in the US used an RFID based solution to track its workers on their university construction projects (Constructech, 2012). In all of the use cases of tracking construction workers on site, implementation details were not discussed in detail as these were found in news and magazine articles. However, these news articles suggest that the use of technological tools to track construction workers for safety purposes is being investigated in the construction industry.

Proposals pushing the use of technology to track construction workers on a site are not new in construction research. The use of tracking technologies for maintaining site safety on construction sites has been proposed by academic researchers (Carbonari et al., 2011; Teizer et al., 2013; Wu et al., 2010b). Carbonari et al. (2011) suggest that construction projects should take advantage of advancements in sensing technologies to locate workers who enter hazardous areas. They demonstrated an RFID based safety management tool that tracks and alerts a construction worker when they enter a predefined dangerous area. Jiang et al. (2014, p. 2) encourage the use of real time location based monitoring of construction workers for conducting safety risk assessments, as evidenced by the

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statement “Overall, the development of automatic monitoring technology, especially the real-time location technology for individuals, provides great feasibility for implementation of real-time safety risk assessment”. Teizer et al. (2013) similarly argue

that location information of workers can be used in safety training applications. Construction workers were tracked in a real-time simulated environment to demonstrate how workers can be warned when their proximity is too close to a hazardous area. Wu et al. (2010b) propose the use of real-time tracking technologies be used to study precursors to accidents and near miss accidents to prevent real accidents from occurring in the future.

Lu et al. (2011, p. 105) suggest “By using RFID technology, an affordable employee tracking system can be developed to provide real-time information, which is critical for construction safety”. An investigation of accident data suggests that 25% of all

construction fatalities are related to proximity of workers to construction equipment (Teizer et al., 2010a). Ultra wide band technology was successfully used in a large open construction site to track location of resources within the site, including equipment and workers (Cheng et al., 2011). RFID tags were used in association with Zigbee networks, another radio frequency based sensing technology, to check if construction workers were wearing their personal protection equipment (PPE) (Barro-Torres et al., 2012). The PPE's themselves were tagged with the RFID equipment and thus enabled the contractors to verify that all the necessary PPE's were present as they passed through check points where RFID readers were placed (Barro-Torres et al., 2012). Vision based tracking technologies (i.e., video cameras) can be used to identify the presence of construction workers. However, this is not practical to use inside a building under construction as it is a ‘line of sight’ based technology and moreover cannot be used to identify individual construction workers (Brilakis et al., 2011). Furthermore, since the environmental conditions on a construction site are constantly shifting, physical obstacles may hinder ‘line of sight’ based technologies for worker tracking.

Locating workers in areas where they are not trained to be present or when dangerous conditions exist in an area are addressed by the studies that have considered location

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literature has shown that the accidents on construction sites occur due to several factors including inadequate design considerations, poor safety culture within the company, in- effective training provided to workers, lacking supervision on site, attitude of individual workers on site, etc. In the consideration of unsafe acts by workers, location monitoring allows the safety manager or superintendent to consider a situation where a safety incident might occur. Specifically, what the worker is doing at that location has not beet addressed in the studies found in the literature. Several studies suggest that safety must be considered from a comprehensive lens (Coble, 2000; Hislop, 1999; HSE, 2003a; McDonald et al., 2009). Therefore the role of location monitoring in maintaining site safety has to be considered a small part of the overall strategy to maintain a safe work environment.

An analysis of the literature suggests that experts agree that knowing the location of construction workers on site, in real time is important for successful safety management. Use cases of tracking the location of workers for safety purposes have been found in various types of construction projects. The use of RFID and similar wireless technological tools was proposed and demonstrated for safety management systems. The issue of location tracking for safety purposes is further examined in Section 2.9 of this thesis.