Stepping forward for challenges in Health, Safety and Environment in GIS perspective 7. Adoption inevitable Case study I--------Dr. John Snow's paradigmatic analysis of the 1854 cholera outbreak in Soho, London This first case has been taken for discussion as it is the most referred case in text book and its advantages as a structured teaching case are numerous. The presentation of this case is therefore not only necessary for medical cartographers but also for GIS developers in Health & Safety sector to portray breakdown of events and its explanation in a spatial context. Hand made maps of disease outbreaks in both Europe and North America are a precedence to Dr. Snow's case(Jarco 1970; Stevenson 1965). Dr. Snow gathered data on deaths from the General Register Office-the office charged with collecting such data-from other physicians, and in a survey of affected houses that he personally conducted (Snow 1855a, 39). In his own investigations he attempted to ascertain from relatives of the deceased where they had gotten their drinking water. Technical Issues--------John Snow (1855b) is often said to be the first person to use what today are called Thiessen or Voronoi polygons to map one source of locational data upon another, a fundamental contribution to analytic mapping (McLeod 2000; Brody 2000). This basic form of proximity analysis creates catchment areas based on the proximity of point-based data attributes, in this case the location of the water sources (McLeod 2000, 133; Brody 2000, 4). The intent of this case study was to introduce the paradigmatic case of early epidemiology and public health & safety to GIS users carrying out data analysis using GIS(Whitehead 1855, 96-97).. In this simple, localized study the GIS approach provides a number of advantages. First and foremost it is relatively fast. Snow took days to calculate his polygon around the Broad Street pump, something the GIS program does in seconds. Secondly, it provides an array of potent techniques-like nearest neighbor analysis and the spatial (or weighted mean) unavailable to Snow and his contemporaries. Third, the ability of the GIS database to summarize and analyze data at a range of scales-local, regional, national and international-is an enormous boon. Discussion & Results He carried out a buffer analysis, nearest neighbor analysis and carried out the mapping. In effect, buffering around individual deaths gives us Snow's perspective, one of apparent centrality. Buffering of the pumps permits a first attempt at quantifying that centrality. While using Snow's general insight as a hypothesis, GIS provides critical tools that permit to go beyond Snow's general approach. Nearest neighbor analysis in GIS permits the elements of two distinct data sets to be analyzed based, in this case, upon the distance between each member of the first set and the nearest member of the second set. Figure 1 shows the percentages of deaths that were being observed and marked by Dr Snow as a part of his initial GIS. This graph has been compiled by taking into consideration the number of deaths in the close vicinity of the wells from where the water has been consumed. This shows a clearer picture of the effect of distance on the deaths. This is also one way of representation along with a map of deaths that were made by marking the location of each death. This could of great help to EHPs for decision making and planning.  Figure 1: Percentages of death in relation to distance Source: Values derived from Dr. John Snow's paradigmatic analysis of the 1854 cholera outbreak in Soho, London This analysis was particularly in a GIS context how ever for an EHP the following points may be of concern for Health & Safety Inspection in the same scenario: Spatial--------Identification of source (location) to cause the disease. Sample Details--------Sample locations to overlap the buffers. Risk Factor Analysis--------As in this case the outbreak of cholera and the deaths resulting from it has been observed more in the areas nearer the well and 87 % deaths were of those who have directly taken water from these wells. An EHP can carryout this analysis through a customized GIS for Health & Safety by plotting the individual deaths, area of residence, source of contamination and the latest health & safety standards for periodical checks. Inspection, Visits and Actions--------All these activities are interlinked. The sites are identified and after an inspection it is given a category and the further action is dependent upon the nature of threat. As in this case the well had to be closed and people were warned. Case Study II--------Sea Impress oil spill On the 15th February 1996 the massive oil tanker Sea Empress was grounded at the entrance to Milford Haven, Wales. As a result of this about 72,000 tonnes of Forties Blend crude oil (FBCO) and 360 tonnes of heavy fuel oil (HFO) was released over several days. The Countryside Council for Wales (CCW) methods was simply to record visible oil affecting a range of habitat categories based on Ordnance Survey 1:10000 mapping (sand/mud flats and beaches, shingle, saltmarsh and rocky shores). The total length of coastline was standardised at the 1:10,000 digital Ordnance Survey High Water Mark (HWM). Oiling was classified as sheen, medium oiling, heavy oiling and thick mousse. Oiling Using rasterised Ordnance Survey 1:10000 maps displayed on screen each area affected by oiling was identified and a polygon defining the area created. Each polygon was labeled according to the type of oiling. The date of survey was recorded, as the maps only reflect the state of the shore on that time. It may be that areas covered in light oil one day may have been heavily oiled the next. The most recent surveys have been joined into a single coverage (called OIL_COV) using the arc command IDENTITY. This creates a set of polygons and lines (high and low water marks) coded to show the degree of oiling. The high and low water marks have been derived from OS 1:10000 boundary line data. Habitats The habitat information was captured from 1:10000 OS maps. Five different categories were used. The inter-tidal zone has been attributed using these definitions. Where no polygon exists in the OS data for the inter-tidal zone one was created. Map production Maps of the survey were produced using ARC/INFO. The maps show the type of oiling, protected sites and nature reserves on an Ordnance Survey 1:10000 background map. The coastline was divided into a series of segments This unique code was subsequently used to attach the digitized segments to the information on a Shoreline Cleanup Assessment Team (SCAT) form. This information included the shoreline habitat, nature of oiling, and weather conditions. This was subsequently entered into CCW's SCAT database. The GIS data was captured using the same method as for the initial survey. Polygons were used to divide the high and low water marks into a series of coded segments. Discussion & Results The use of GIS in this case has brought following benefits: Spatial--------Although a complete organization was set up to look into the matter as it was beyond the control of Health & Safety Department of the Council. However the base line remains the same. CCW was required to produce maps of the impacted coastline to check the extent of damage to environment and nature. GIS provides the ideal storage and retrieval system for this data. Health & Safety Details--------One of the main advantages was the ability to overlay data with other data sets, such as health & safety details of protected sites information. The information system can be further embellished as other data sets become available. Keeping in view these datasets a better picture can be drawn for good planning and HACCP formulation. Risk Factor Analysis--------The risk analysis of the sample that has been obtained by the ground surveyors was carried out. As is done previously the hand drawn maps would have made the data difficult to retrieve making comparisons between surveys extremely difficult. Furthermore analysis of the data would have been time consuming. This would have limited the degree of analysis. A GIS integrated with Health & Safety information provides scope for more detailed interrogation of the data using procedures that can be standardized amongst several different organizations. Sample Details--------The Samples were collected by keeping in view the spatial dimensions. During the spill GIS was used to calculate lengths of coastline affected, and was able to accurately pin point the protected sites in the impacted area. Without GIS it would have been very difficult and time consuming, to calculate the lengths of coastline and the component habitats. GIS was also used to project protected sites information onto Admiralty Charts. The sites were provided as an overlay as the Charts were not in a format readily available for GIS. The movement of the spill was then plotted daily onto the chart. Without GIS this information would have been plotted against the OS National Grid and then transformed to Mercator projection to fit the Admiralty Charts. GIS Methodology--------The coastline affected by the oil spill was mapped at 1:10000 scale. This data was then captured digitally using ESRI's ARC/INFO GIS software. It was then combined with other information stored in the GIS, e.g. protected sites, to produce maps of the affected area. Habitat information for the affected coastline was also captured showing the extent of affected habitats.The GIS is also being used to store other spill-related information, such as the locations of environmental samples taken by all the various agencies involved in the response. 8. Recommendations Health & Safety market of UK is an ever growing market. The lack of relevant data at macro level regarding health & safety inspections for health & safety at work needs more deliberation and an addition of spatial context for future analysis is required. Although statistics at larger spectrum are available but for a GIS analysis the missing links are the interlinking of the data to a known geography with the environmental health expenditure. This includes the capital expenditures and services through flexible resourcing companies. The lack of information in private & public sector does make this analysis difficult for prediction of the exact market analysis of Health & Safety sector. There is also need to educate the Environmental Health Practitioners to learn the use of GIS for Health & Safety. Point data is an essential tool to pinpoint the individual location or entity and is essential to maximize the benefits of GIS for public health research in health & safety sector. In the case of health related data, point data could consist of individual patients' home or occupational addresses, or where individuals came into contact with disease vectors, outbreaks or any Health & Safety risks. The recording and presentation of point data does not present any special problems in the traditional domains of GIS, where the data involved generally refer to objects like industries, work places etc. In contrast, point data are generally not available for social and health & safety applications of GIS where datasets consist of information about human beings, due to ethical, ideological and legal considerations for the maintenance of personal privacy. For some research applications, such as the definition of disease prevalence, it is sufficient to use aggregated data about groups of people. But, for more sophisticated research aimed at determining possible causal relationships or for longitudinal studies, data relating to identifiable individuals are essential. The important point here is that the most commonly used way of protecting confidentiality of individuals or small group is the aggregation of point data to area data. Pakistan being a developing country needs to strengthen its base in terms of technology and data acquisition in the fields of health, safety and environmental protection to make utilization of this technology. 10. Conclusion The health & Safety market is not as regulated in Pakistan as in case of UK, it requires quality tools for monitoring and optimizing networks. There is a need to customize GIS setup for Health & Safety sector. GIS is still largely uncharted territory for most public health researchers and EHPs and the association with GIS can be overwhelming. Those promoting GIS for health and safety research and health & safety at work must emphasize the importance of the spatial component to researchers from various disciplines. Otherwise there is a real risk that many health and safety researchers and EHPs may only use GIS for its mapping functions, not realizing that to gain maximum benefit from the technology their project must exploit its sophisticated spatial (as distinct from statistical) analytical capacity. The need to understand space, location and distribution, particularly of environmental and social phenomena, highlights the role of geographers and other spatial analysts in health and safety research using GIS. In the increasingly information-intensive environment of tomorrow's health and safety, the role of GIS will have greater importance due to its abilities to integrate a wide range of data sources, from legacy systems to image data, and to make complex data more quickly and easily understood. The breakdown of Health & safety inspection in a GIS perspective is just one aspect of Environmental Protection and Health & Safety. This needs to be looked in detail of how the things shall be implemented at National level so that the benefits can be reaped at an individual level. References
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