Areal Location Of Hazardous Atmospheres Research Articles

Model and Analysis of Economic- and Risk-Based Objective Optimization Problem for Plant Location within Industrial Estates Using Epsilon-Constraint Algorithms

In many countries, a number of industrial estates have been established to support the growth of the industrial sector, which is an essential strategy to drive economic growth. Planning for the location of industrial factories within an industrial estate, however, becomes complex, given the various types of industrial plants and the requirements of utilities to support operations within an industrial park. In this research, we model and analyze bi-objective optimization for locating plants within an industrial estate by considering economic- and risk-based cost objectives. Whereas economic objectives are associated with utility distances between plant locations, risk-based cost is a surrogate criterion derived from safety considerations. Next, risk-based data are further generated from Areal Locations of Hazardous Atmospheres (ALOHA), the hazard modeling program, and solutions to the bi-objective model are obtained from the Epsilon-constraint algorithm. Finally, the model is applied to a regional case study in a Thailand industrial estate, and the Pareto frontier is evaluated to demonstrate the trade-off between objectives.

Determination of emergency assembly point for industrial accidents with AHP analysis

Major industrial accidents, which are a type of technological disaster, are very important due to the security risks and financial damages that threaten the environment and human health in today's industrialization. In this study, it was aimed to propose an approach that will guide the decision makers to choose the emergency assembly point that should be in the distance or shelter where the employees will be not affected by the negative consequences of emergencies within the scope of the obligation of industrial establishments preparing an internal emergency plan for major industrial accidents. For this purpose, in the first stage, modelling studies were carried out with ALOHA (Areal Locations of Hazardous Atmospheres) Software over possible accident scenarios in an industrial establishment containing different types and amounts of hazardous chemicals. As a result of modelling studies, possible toxic emissions, fire and explosion effect distances and threat zones for the industrial establishment were obtained. In the second stage, the weights of the main and sub-selection criteria to be used in determining the assembly point were calculated. This stage was carried out based on the comparison data obtained as a result of the questionnaire applied to professionals with the help of AHP (Analytic Hierarchy Process) method, which is one of the multi-criteria decision making methods. In the last stage, three candidate points were selected considering the physical effect areas determined in the first stage in the boundaries of the establishment, where the employees were evaluated to be affected the minimum from the negative consequences of industrial accidents. These candidate points were evaluated again with the AHP method on the basis of the sub-criteria whose relative weights were determined in the second stage and a selection was made. As a result, an approach that provides the solution of our problem was obtained.

Influence of Evacuation Policy on Clearance Time under Large-Scale Chemical Accident: An Agent-Based Modeling.

Large-scale chemical accidents that occur near areas with large populations can cause significant damage not only to employees in a workplace but also to residents near the accident site. Despite the increasing frequency and severity of chemical accidents, few researchers have argued for the necessity of developing scenarios and simulation models for these accidents. Combining the TRANSIMS (Transportation Analysis and Simulation System) agent-based model with the ALOHA (Areal Location of Hazardous Atmospheres) dispersion model, this study aims to develop a modeling framework for simulating emergency evacuations in response to large-scale chemical accidents. The baseline accident scenario assumed the simultaneous leakage of toxic chemicals from industrial complexes near residential areas. The ALOHA model results showed that approximately 60% of residents in the scenario’s city were required to evacuate their homes. The majority of evacuees completed their evacuations within 5 h in the baseline scenario (evacuating maximum number of private vehicles without any intervention), while the distribution of the population and street network density caused geographical variability in clearance time. Clearance time can be significantly reduced by changing both the evacuees’ behaviors and the evacuation policy, which suggests the necessity for proper public intervention when the mass evacuation of residents is required due to chemical accidents.

HAZOP and ALOHA Analysis of Acetone

A potential hazard can happen because of a technical and personal failures, natural disasters, terrorist attacks, and fires. The potential hazards can be dangerous for human health and environment, also cause economic losses. In an industrial plant, prevention and control of these consequences have an importancy. Hazard and Operability Analysis (HAZOP) is a technique for a system evaluation and determination of risk management of hazards. In particular, HAZOP is used in order to determine potential hazards in a system and operability problems. Moreover, Areal Location of Hazardous Atmosphere (ALOHA) is the potential hazard modelling programme, which is used to plan chemical emergencies. Acetone, a colorless liquid also known as propanone, is a solvent used in manufacture of plastics and other industrial products. The most hazardous property of acetone is its flammability. Acetone is a solvent widely used in the chemical industries and stored in large volumes, therefore, acetone is an important source of danger for chemical processes.  In this study, acetone was investigated to be a hazardous chemical using HAZOP and ALOHA software in order to prevent and control a big hazardous event in an industrial plant. 

Feasibility Evaluation of Designated Quantities for Chemicals Requiring Preparation for Accidents in the Korean Chemical Accident Prevention System.

To prevent chemical accidents, the United States (US), the European Union (EU), and the Republic of Korea operate legal systems, such as risk management plans (RMP) and process safety management (PSM), to prevent chemical accidents inside and outside the workplace. The duty to implement chemical accident prevention systems and the criteria for being a target workplace are dependent on the designated quantities of chemicals handled. A chemical accident prevention system is obligatory for storage and handling of legally declared chemicals in the workplace. Benzene, toluene, xylene, methyl ethyl ketone, and ethyl acetate are all flammable materials that are commonly used as solvents in the chemical industry. These substances are grouped into flammable substances groups in the US and the EU, and are managed with the same designated quantities. However, in Korea, the designated quantities are: benzene, 10,000 kg; toluene, xylene, and methyl ethyl ketone, 200,000 kg; and ethyl acetate, 20,000 kg. In order to evaluate the validity of the chemical quantities, fire explosion scenarios during chemical accidents were modeled using two modeling programs, Areal Location of Hazardous Atmosphere (ALOHA) and Korea Off-Site Risk Assessment Supporting Tool (KORA) software, under the same conditions. Similar damage radii were found for the five flammable materials with both pool fires and vapor cloud explosions (VCE). Based on these damage radii, the designated quantities of five substances were calculated and included in the range (10,000 to 13,500 kg). The results show that current designated quantities underestimate chemical substances, and for the prevention of accidents and post-management after chemical accidents, it is necessary to manage flammable substances under one grouping.

Influence of monsoon seasons on accidental chlorine leak and dispersion around Gebeng industrial area

This paper presents the prediction of hypothetical chlorine leak dispersion around Gebeng industrial area using Areal Location of Hazardous Atmosphere (ALOHA) software. The effect of the different wind speed and direction to chlorine dispersion in the meteorological microscale area was investigated. The wind speed ranging from 1.32 to 10.7 m/s obtained from a local weather station was considered. Heavy gas dispersion model was used to determine the concentration of chlorine plume within the area of concern. The leakage rate was set to correspond to a leakage from the chlorine tank at 792 kg/h. The result showed that the residential areas R1 and R2 are affected by the plume dispersed by southwest and northern winds, respectively. A greater hazard area was found when the wind speed is below 2.3 m/s. Meanwhile, the hazard zone reduced to nearly half when the wind speed is above 5.4 m/s. The appropriate evacuation routes were developed to reduce risk of exposure to toxic gas. Finding from this work is useful to understand the risk of noxious gas dispersion around Gebeng industrial area.

Designing an effective mitigation system based on the physical barrier for hazardous chemical leakage accidents

An evaluation module based on the liquid discharge trajectory equation was developed to improve the safety as a result of chemical leakage accidents. An evaluation was performed on leakage based on changes in the vessel pressure and discharge height during a leakage accident involving a vertical storage tank containing 35% hydrochloric acid (HCl). In addition, areal locations of hazardous atmospheres (ALOHA) and the Phast program were used to evaluate the impact and dispersion range of the discharged hazardous chemicals. The evaluation results showed that installing the mitigation system resulted in a maximum 72.8% reduction in the damage impact range in the emergency response planning guideline (ERPG)-2 distance. It was also confirmed by the Phast analysis that the dispersion range and pattern were changed according to the presence of a dike. The dispersion range decreased by up to 40% depending on the presence of the dike. It was concluded that the dispersion range is related to the physical and chemical characteristics of hazardous chemicals.

Modeling of Ammonia Emission in the Petrochemical Industry

Background: Ammonia is a commonly used chemical in the process industries. Chemical leakage is one of the main problems threatening the staff, facilities, and the environment in the process industries. Objectives: The aim of this study was to model the emission of ammonia and its consequences in the petrochemical industry. Methods: In this study, three accident scenarios of the most probable ones were chosen, including toxic vapor cloud, jet fire, and boiling liquid expanding vapor explosion (BLEVE). Then, the scenario modeling was done using areal locations of hazardous atmospheres (ALOHA) software. Results: In the first scenario, the total released ammonia is 81,316 kg. The concentration of ammonia toxic vapor is greater than 1,100 ppm (AEGL-3 region) at a distance of 1 km, which might cause death in 60 seconds. The overpressure never exceeds 3.5 psi; thus, there is no possibility of serious injury or destruction of buildings. In the third scenario, the thermal radiation of BLEVE is greater than 10 kW/m2 at a distance of 376 m, which is potentially lethal within 60 seconds. Conclusions: One of the main risks in petrochemical companies is the leakage of ammonia. The toxicity of ammonia is the most significant threat to people. The overpressure of vapor cloud explosion does not cause serious injury or of building destruction. The thermal radiation from jet fire and fireball has no effect on the city while it may cause death to the staff within 60 seconds. Thus, safety precautions should be considered to prevent the consequences of leakage accidents.

Odor impact zones around landfills: Delineation based on atmospheric conditions and land use characteristics

Odors emitted from landfills can result in complaints by the residents living near the landfills. The aim of this study was to develop an assessment and delineation tool to identify the areas which can be impacted by the odors released from landfills based on land use characteristics and atmospheric conditions; and estimate the number of people who may be impacted. Odor emissions and dispersion analyses were conducted for three case study landfills under different atmospheric conditions in view of the land use characteristics around each landfill. Odor emissions and odor intensity levels were estimated based on the total gas production and the level of odorous compounds present in the landfill gas using the Landfill Gas Emissions Model (LandGEM) software. To delineate the odor impact zones, air dispersion characteristics of the odorous gases were analyzed using the dispersion modeling software, Areal Locations of Hazardous Atmospheres (ALOHA), and mapped using ArcGIS. Impact zone analyses were conducted based on the odor perception thresholds. The methodology developed involved coupling landfill gas emissions model (LandGEM), dispersions model (ALOHA) and mapping software for land use and population density (ArcGIS) allows visualization of the potential impact zones for preliminary delineation of the buffer zones around landfills, developing appropriate mitigation measures in view of the changing land use characteristics and population density around the existing and planned landfills. The odor impact zone delineation methodology was named Land-OZ (short for Landfill Odor Impact Zone). Results of using the odor impact zone tool showed that atmospheric stability could increase the odor impact radius around the three landfills evaluated between 340 and 1100 percent depending on the land use characteristics of the surrounding areas.

Assessment of an ammonia incident in the industrial area of Matanzas

This study describe and quantifier the effects of a virtual ammonia release accident from tanks in the industrial area of Matanzas on the population and the environment. Climate data of the study area were characterized using the Areal Locations of Hazardous Atmospheres (ALOHA) software which entails different scenarios. Predictions for three of them include: “Toxic Vapor Cloud”, “Flammable Area” and “Vapor Cloud Explosion”. The results show that the worse scenario is the toxic cloud of ammonia affecting a vast area with a dense population and causing environmental damage. Under this scenario 294 casualties should be expected.

Flammable Substances in Korea Considering the Domino Effect: Assessment of Safety Distance.

Benzene, toluene, and xylene (BTX) are flammable substances used in a wide range of raw materials and products. Chemical accidents caused by flammable substances are different from leakage accidents of toxic materials. Initial explosions and fires may cause secondary or tertiary explosions, or fires with nearby flammable materials. This is called the domino effect. In cases of leakage accidents, it is possible to prevent accidents through early control of the leakage to the outside or by bypassing, but it is difficult to cope with explosions because they occur instantaneously. To prevent explosions due to the domino effect, a safety distance must be set. Safety distances vary widely by country. In the case of the United States (US) or the European Union (EU), safety distances are set in various ways depending on the chemical industry and the amount of flammable substances being handled. However, countries such as Korea, Taiwan, and Dubai have comprehensive regulation, and the safety distances are small. In this study, we simulated the range of overpressure at which other chemical equipment could explode when an explosion occurs in a flammable BTX storage tank. There are three types of analysis methods of vapor cloud explosion. PHAST (Process Hazard Analysis Software Tool) and ALOHA (Areal Location of Hazardous Atmosphere) were selected to model explosions using three methods (trinitrotoluene equivalence method, the Netherlands Organization multi-energy method, and Baker-Strehlow-Tang method). The results indicated that the safety distances in the US and EU showed low probability of a domino effect, but those in Korea, Dubai, and Taiwan could lead to a secondary explosions. Therefore, it is necessary to propose a reasonable method to determine safety distances considering the amount and physicochemical characteristics of the flammable substances being used.

Investigation of an Explosion at a Styrene Plant with Alkylation Reactor Feed Furnace

To prevent and mitigate chemical risks in the petrochemical industry, such as fires and spillage, process safety management (PSM), is essential, especially where flammable, corrosive, explosive, toxic, or otherwise dangerous chemicals are used. We investigated process safety (PS) between man–machine (material equipment) and environmental interfaces by using process hazard analysis (PHA) and fault tree analysis (FTA). By analyzing the data obtained through machinery and mechanical integrity (MI), pre-startup safety review (PSSR), current operating modes, and areal locations of hazardous atmospheres (ALOHA) simulations of the disaster’s aftermath, the cause of the styrene plant accident was found to be the fuel furnace (F101) switching process. Although the furnace had been extinguished, fuel continued to enter the furnace, and it was exposed to a high-temperature surface, resulting in the flashing ignition of the C4 fuel. The plan-do-check-act (PDCA) management model can be used to forestall the system from accident, and it is used to improve the proposal and develop countermeasures that would increase PSM performance and substantially lessen the impact of the thermal hazard. Disasters are often attributable to the unsafe state of machinery, equipment, or the environment, dangerous behaviors of the operator, and the lack of a thorough management system. It is anticipated that the investigation and analysis of the accident would not only find the real cause of the disaster but also lead to the establishment of better effective solutions for common safety problems.

ANALYZING DOMINO EFFECTS OCCURRING ON GASOLINE STORAGE TANKS AT THE BULK OIL STORAGE AND TRANSPORTATION (BOST) DEPOT

Since processed crude oil products are very vulnerable (susceptible) and highly flammable to cause massive catastrophes, such as fire and explosion, which are frequent and can create a chain reaction (Domino effects). This research was carried out at the Bulk Oil Storage and Transportation LTD depot on the Accra plain in Ghana where gasoline and Gasoil are stored. The research was conducted on a flammable gasoline area subjected to a vapor cloud explosion and the hazardous zone. Analyzing domino effects, propagation of a gasoline flammable vapor cloud caused by the explosion, ALOHA (Areal Location of Hazardous Atmospheres) software was used to find out how to apply effective safety measures to prevent future risks at any BOST facilities across the country. After the analysis, it was realized that 5.0 miles to the west-south-west the fuel concentration in the air was 2100 ppm lower than the explosive limit (LEL), and could not be as severe as that at 2.3 miles distance from the source point (12600 ppm LEL) with a greater fuel concentration in the atmosphere. The results made available would be useful in maximizing (improving) safety at the facility, residential area, and as well as minimizing future incidents.

Sensitivity Analysis of Weather Variables on Offsite Consequence Analysis Tools in South Korea and the United States.

We studied sensitive weather variables for consequence analysis, in the case of chemical leaks on the user side of offsite consequence analysis (OCA) tools. We used OCA tools Korea Offsite Risk Assessment (KORA) and Areal Location of Hazardous Atmospheres (ALOHA) in South Korea and the United States, respectively. The chemicals used for this analysis were 28% ammonia (NH3), 35% hydrogen chloride (HCl), 50% hydrofluoric acid (HF), and 69% nitric acid (HNO3). The accident scenarios were based on leakage accidents in storage tanks. The weather variables were air temperature, wind speed, humidity, and atmospheric stability. Sensitivity analysis was performed using the Statistical Package for the Social Sciences (SPSS) program for dummy regression analysis. Sensitivity analysis showed that impact distance was not sensitive to humidity. Impact distance was most sensitive to atmospheric stability, and was also more sensitive to air temperature than wind speed, according to both the KORA and ALOHA tools. Moreover, the weather variables were more sensitive in rural conditions than in urban conditions, with the ALOHA tool being more influenced by weather variables than the KORA tool. Therefore, if using the ALOHA tool instead of the KORA tool in rural conditions, users should be careful not to cause any differences in impact distance due to input errors of weather variables, with the most sensitive one being atmospheric stability.

Use and limitations of offsite consequence analysis tools from South Korea and the United States in hydrogen fluoride accidental release.

We investigated the characteristics and limitations in the event of hydrofluoric acid (HF) leakage by comparing and analyzing the offsite consequence analysis (OCA) tools based on the chemical plant operating conditions. We reviewed the tools Korea Offsite Risk Assessment (KORA) from South Korea and Risk Management Plan*Comp (RMP*Comp™) and Areal Location of Hazardous Atmospheres (ALOHA) from the United States. The scenario studied was based on a leak event from a 50% HF aqueous solution storage tank, and the operating conditions taken into consideration were the operating temperature and dike installation conditions. The results from the OCA differed; KORA presented a smaller range of offsite impact than did ALOHA. The offsite impact ranges of KORA and ALOHA increased as the operating temperature and dike installation area increased. However, RMP*Comp differed greatly in its offsite impact range results in the operating temperature range of 25 °C to 30 °C. Moreover, in the alternative scenario, a limitation existed in that the offsite impact range was not changed by the dike installation conditions. The offsite impact range analyzed via KORA and ALOHA reflected the reality of an HF leak accident better than that analyzed via RMP*Comp. Therefore, it is more reasonable to use KORA and ALOHA instead of RMP*Comp in OCA. Moreover, users should realize that ALOHA has a somewhat wider range of offsite impact than KORA does in OCA. The separation distance from the storage tank when installing a dike is effective between 1 and 1.5 m in consideration of securing the minimum workspace for workers. Integr Environ Assess Manag 2018;14:205-211. © 2017 SETAC.

An Atmospheric Dispersion Modeling Microservice for HazMat Transportation

In most hazardous materials (Hazmat for short) transportation systems, the purpose is to reduce the risk-cost from origins to destinations. This makes the hazmat system more complicated when compared to many other transportation systems. There are different models for considering risk in a hazmat transportation, the most broadly used is the so-called “traditional risk model”, through which the risk is defined as the product of two parameters: (a) the probability of an accident; and (b) the consequences of the accident. The consequences depend on other factors such the threat zone, which indicates the geographical area in which an atmospheric release of a substance would affect a given area during a specified time period. Moreover, the dispersion of pollutants within the accident area is a function of weather parameters such as wind direction, wind speed, atmospheric stability, which changes instantly in the real world. Thus, the weather system changes the risk parameters by changing the area impacted by a hazmat accident. Hence, it is difficult to identify and to tell the dispersion of a substance. The aim of this work is to develop the microservice that focuses on the computation of dispersion model and to identify the coverage of the affected area through the simulation software Areal location of Hazardous Atmosphere (ALOHA). The proposed microservice uses emission source, accident location and real-time meteorological data near to the sources, to provide necessary and accurate results rapidly. It can be used to more accurately simulate the atmospheric evolution of the released material in both time and space, for decision making and real-time response to save lives and to evacuate peoples to safety during a disaster release.

Quantitative fire and explosion risk assessment of fuel tanker truck: Preliminary case study at fuel terminal x jakarta

The distributions of fuel using tanker truck have been increasing in terms of complex risks related to the potential of fire and explosion. Various studies and case reports have proven that the level of accidents or fire and explosions of fuel tanker trucks is rising. The objective of this study is to calculate personal and societal risk levels. Preliminary case study was conducted in filling shed of the Fuel Terminal X Jakarta. Data on locations, materials, meteorology hazard identification, activities and process, case reports, and installation were collected from measurements, observations, or interviews processes, as well as provided by the company and from existing literatures. Individual Risk per Annum (IRPA) for individual risk and Potential Loss of Life (PLL) for societal risk were calculated from frequency analysis using Event Tree Analysis (ETA). Furthermore, the consequences were analyzed using Areal Location of Hazardous Atmosphere (ALOHA® 5.4.4) software of fire and explosion based on a worst-case scenario modeling. The individual risk per year for office workers, field workers, society and road users were 4.16E-09; 6.99E-09; 1.73E-08 and 6.59E-13, respectively. The societal risk was 1.49×10−5 per year. Compared to the UK HSE Risk Criteria, the findings showed that the individual and societal risks of each category were still acceptable and tolerable.

Areal location of hazardous atmospheres simulation on toxic chemical release: A scenario-based case study from Ray, Iran.

Background and aimChemical accidents cause significant danger for residents living close to chemical facilities. For this reason, this study assessed the impacts of a simulated chemical accident on surrounding residents in the city of Ray, Iran.MethodsIn this scenario-based case study in 2015, the Areal Location of Hazardous Atmospheres (ALOHA) model was applied to simulate a toxic chemical release from a chlorine warehouse in Shourabad, Ray, Iran. The population of the area was calculated based on the latest census in Iran, 2011. The atmospheric variables included were wind speed, air temperature, and relative humidity. We also included data on pollution source such as diameter, length and volume, and condition of chemicals. The simulation was repeated for each seasonal period. The simulated threat zones were mapped using Geographical Information System. The percentage of residents sustaining injuries and death was calculated using probit.ResultsThe maximum and minimum simulated threat zones by chlorine release are during summer and winter at 8.8 and 6.4 kilometers respectively. The total affected population was estimated at approximately 30,000 people. The greater percent of injuries and death was estimated to occur in the winter and autumn, compared to summer and spring, because of greater climatic instability. The number of individuals affected by chlorine release in the spring, summer, autumn and winter at 8.3, 8.8, 7.6 and 6.4 kilometers, are estimated at 22,500, 25,000, 28,100 and 27,500, respectively. Populations located in hot and warm zones of toxic chemical releases should have access to medical resources.ConclusionsThe results showed that relevant factors impact human vulnerability, and these should be examined to mitigate the harmful consequences of chemical accidents. Establishing a multi-level Emergency Response Program is also recommended in the area under study.

Skenario Konsekuensi Analisis Pengangkutan LNG Semarang-Yogyakarta dengan Simulasi ALOHA

Liquefied Natural Gas (LNG) is one of the potential alternative fuels to replace conventional fuels. Using LNG as fuel in Indonesia especially Yogyakarta will give many advantages, for instance, reduced greenhouse gas emissions so that eco-city in Yogyakarta can be realized. Although LNG has many advantages, LNG still contains many hazards whether during storage or distribution, the major hazard is radiant heat. This study aims to analyze and simulate hazard scenarios when transporting LNG such as fire pools, fireballs and vapor clouds and establishing exclusion zone by Areal Location of Hazardous Atmospheres (ALOHA) simulation. This study assumes that the diameter of the tank leak is 1 in and 3 in. The simulation results the exclusion zone from pool fire’s heat radiation from 1 in and 3 in leaks are more than 14 m and 39 m. While the safe distance of the fireball is 799 m. While in the distance vapor clouds that have a possibility of fire for the diameter leakage of 1 and 3 in are 21 m and 59 m.

FIRE AND EXPLOSION CONSEQUENCE ANALYSIS ON LPG (LIQUEFIED PETROLEUM GAS) TANK IN PT SURYA ESA PERKASA TBK PALEMBANG

Background: LPG plant has fires and explosions hazard which can occur due to a processing, storing, or distributing failure. PT Surya Esa Perkasa Tbk is one of LPG plant in Indonesia which has a high risk of fire and explosion due to leakage of the 150 tons capacity tank. Therefore, it is necessary to analyze the consequences of fire and explosion on the LPG tank in PT Surya Esa Perkasa Tbk Palembang. Method: This study was a descriptive research with quantitative approach. The consequence analysis will be made jet fire, fireball/BLEVE, flammable area/flash fire, and vapor cloud explosion (VCE) modeling by using ALOHA (Areal Location of Hazardous Atmosphere) software 5.4.4 version. The farthest threat zone will be analyzed to know the number of population at risk and analysis of emergency response plan (procedures, teams, facilities and infrastructure) which had been applied. Result: Jet fire modeling threat zone reached 150 meters, BLEVE modeling reached 1.3 kilometers, flammable area modeling reached 911 meters, and VCE modeling reached 398 meters. Population at risk was 81 workers. The application of emergency response plan (ERP) from procedure, team, and facilities aspects had been good but there were no ERP intended for surrounding communities. Conclusion: BLEVE modeling has the farthest consequences reaches 1.3 kilometers with 81 people as population at risk and ERP had been well implemented by PT Surya Esa Perkasa Tbk for workers but it still had no ERP for surrounding community. Keywords: working population at risk, emergency response plan.