Health and Safety management in quarries industry. Ioannis Aspirtakis Mechanical Engineer, MSc, ErgoProlipsis - Health & Safety Services, Greece Michael Galetakis Assistant Professor, Dept. of Mineral Resources Engineering, Technical University of Crete, Greece 1. INTRODUCTION Mining and quarrying industry is an important economic sector in Greece and includes production of mineral fuels (lignite), metal and non metal minerals (bauxite, nickel, bentonite, etc), ornamental rocks (marble, slate, etc) and aggregates (natural and crushed). The estimated value of minerals (fuel minerals and aggregates are excluded) extracted in Greece during 2006 was 1145 million and the exports were 845.6 million (Association of Greek Mining Enterprises, 2007). Aggregates, extracted via quarrying operations, are essential for the development of any modern economy since they are used extensively for all construction applications. More than 240 quarries operate in Greece with an annual production of 60 million tones of crushed aggregates (Institute for the Economy of Constructions, 2002). While quarrying is critical in the supply of raw materials, which are essentials for the economic development, quarries remains hazardous environment to work within. According to statistics of the Mines Inspection Agency of Greece (MIAG), the average fatality rate (number of fatal accidents per 100,000 workers) for the overall mining and quarrying sector was 37.7 for the period 1988-2002. This value is significant higher to those of the three following hazardous working environments which are: constructions (14.7), agriculture (14.0) and transportations (13.7) (Georgoulakis and Grigoroglou, 2000). The variation of the fatality rate in mining and quarrying sector, shown in figure 1, indicates a slightly decreasing trend during 1987-2002. Further statistical analysis of data conducted by MIAG (Figure 2) indicates that the fatality rate for aggregates quarrying, ornamental rocks quarrying and mining was 107.5, 76.5 and 16.5 respectively. According to MIAG the extremely high fatality rate of quarrying in Greece is close related to the small size of these enterprises (ten workers in each, on average) that it a limiting factor in developing an effective safety management system. In order to improve occupational safety and health in quarrying, systematic planning of appropriate safety programs and measures are required. The safety management decisions which must be made to select and prioritize problem areas and safety system weaknesses must be based on the recognition of hazards encountered in each activity of the quarrying process. For this purpose, a systematic application of the risk assessment and management concept may provide needed support.
Figure 1. Variation of fatality rate (number of fatal accidents per 100000 employees) for the mining and quarrying sector in Greece, during 1987-2002 (the thick line shows the trend). 70,0 fatality rate (per 100000 employees) 60,0 50,0 40,0 30,0 20,0 10,0 0,0 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 Year Figure 2. Fatal accidents, fatality rate and number of workers per mine type, during 1987-2002 (MIAG, 2002). 120 100 Number of fatal injuries Fatality rate Number of workers 12000 10000 80 60 40 8000 6000 4000 Number of workers 20 2000 0 Quarries (aggregates) Mines Quarries (ornamental stones) 0
2. HEALTH AND SAFETY MANAGEMENT Health and Safety management is a systematic way to control all possible hazards that might lead to unsafe conditions for employees, facilities or equipment of a company. For maximum efficiency Health and Safety management can be applied in 6 steps (Kiritopoulos et al, 2004 - Drivas et al, 1997): 1) Hazard identification 2) Involved employees or equipment 3) Quantitative risk assessment 4) Risk control through preventive or corrective actions 5) Risk monitoring 6) Process review Hazard identification, is one of the most important aspects of Health and Safety management. During this identification, an analytical list of hazards is applied through all working places and involved parties including employees, visitors or subcontractors (EKA - ELINYAE, 2004 - Greek Ministry of Development, 2007). Risk assessment is the procedure of consequences evaluation, through qualitative or quantitative methods, depending on the complexity of the operation that is being examined. According to risk assessment results, appropriate preventive or corrective actions are applied. Additionally risk monitoring and process review, are necessary steps in order to ensure continues improvement among working places. 3. HEALTH AND SAFETY MANAGEMENT IN QUARRIES INDUSTRY 3.1 Hazard identification and involved employees. Hazards in quarries are mainly linked with heavy moving vehicles, working equipment, use of explosives, dust in working places, high noise levels and lack of ergonomical design. Heavy moving vehicles such as dump trucks, loaders, excavators, backhoes, dozers or graders are likely to present health and safety hazards such as: Vehicle overturn (mostly because of road design and stability) Lack of visibility Inadequate maintenance Inappropriate use Working equipment is also one of the agents that are possible to present health and safety hazards. Crushers, vibrating screens and conveyor belts can lead to serious accidents if moving parts are not covered and the equipment is not well maintained. Unprotected electric panels, unsigned electrical circuits, overhead power lines and unprotected power cables are some of the most electrical hazards, linked with quarrying. Dust and inadequate housekeeping usually make the conditions even worse. Use of explosives is a high hazard occupation in quarry industry. Employees might be in risk because of inadequate training, lack of blasting procedure, flyrock effect, explosive handling, misfires or site nonevacuation while blasting.
By its nature quarrying has the potential to create dust and that s the reason why dust is an agent for serious health hazards. Respiratory diseases are common among quarrying employees while special actions should be taken for crystalline silica exposure. Toxic fumes after blasting can also be a health hazard especially because of CO and NOx high concentration level (Sapko et al., 1999). Heavy moving and installed working equipment creates high noise level, which is one of the most common health hazards among quarries. Additionally, high vibrating levels is now proved that can lead to chronic serious diseases such as Hand-Arm Vibration Syndrome (HAVS) or other musculoskeletal disorders (Wolcott, 2004, ELINYAE, 2003). For effective hazard identification, quarry processes were classified as in Table 1, using appropriate checklists. Involved employees are listed in Table 2. In Table 3, a list of the identified hazards is presented. Table 1. Quarrying processes ID D1 D2 D3 D4 D5 D6 D7 Process Drilling and blasting Loading, uploading, haulage Crushing Screening Maintenance Other quarrying activities Management, accounting Table 2. Involved employees ID P10 P11 P20 P30 P40 P50 P51 P52 P60 P70 P80 Involved employees Drilling operator Shotfirers Dump truck-loader operator Crusher operator Screening operator Electrical technicians Mechanical technicians Welders Workers Clerks, management Visitors, customers, subcontractors 4. RISK ASSESSMENT AND RISK CONTROL 4.1 Risk assessment According to Greek legislation (PD 159/99, article 2, paragraph 6) for an effective risk assessment, the probability of hazard occurrence, the mishap consequence and the probability (frequency) of the employee exposure to hazard, should be taken into consideration. According to above, for risk evaluation the following quantitative model was applied: where, R = P H F (1) R is the risk level (it takes values from 1 to 1000), P is the probability of hazard occurrence (rating from 1 to 10), H is the harm factor (rating from 1 to 10), showing the severity of the mishap, and F is the frequency factor (rating from 1 to 10), expressing the probability of employee exposure to hazard.
Table 3. Example of hazard identification procedure ID Hazard Process Involved employees Α1 Moving vehicles D2-D6 P20-P60 Α5 Lack of maintenance D1-D2-D3-D4-D6 P10-P11-P20-P30-P40-P60 Α6 Rotating or moving parts of working equipment D1-D3-D4-D5-D6 P10-P11-P30-P40-P50- P51-P52-P60 Α8 Explosive handling D1-D6 P10-P11-P60 Α9 Electric circuits D3-D4-D5-D6 P30-P40-P51-P52-P60 H1 Dust ALL ALL H3 Vibration from moving vehicles or working equipment D1-D2- D3-D4 P10-P20-P30-P40 H4 High noise level D1-D2-D3-D4-D5-D6 ALL except P70 By sorting risk list according to risk factor (R), we can classify risks in acceptable (R<200) and unacceptable (R>200) for each company. For the unacceptable risks appropriate preventive or corrective actions are applied. 4.2 Best practices Following recognized best practices, better performance can be achieved and risk factor can be reduced significantly. In order to avoid accidents while operating moving vehicles in quarries, the operator, the road and the vehicle itself should be considered as strong related agents, which should be combined in a safe way (NIOSH, 2002). Operators should be well trained, roads well designed and vehicles systematically maintained in order to avoid unsafe conditions. According to legislation, working equipment should be used only from trained employees. Dangerous areas (e.g. rotating parts) should be isolated or signed and emergency stop should be installed. Working environment is very important for the Health and Safety of employees. Emergency exits should be present and all working places should be stable and robust. Mezzanines and stairs should have protective handrail and floors should be clear without holes and gaps. First aid equipment should be available and an appropriate room for rest. Explosives handling is a very risky procedure and best practices should be applied in order to avoid accidents. Transportation, storage and use of explosives should be a standard business procedure, well monitored and executed only by authorized employees (Papadionisiou, 2001). Smoking should be forbidden and all equipment should be made by non-sparking materials. Appropriate blasting plan should be prepared and all the dangerous area should be evacuated and guarded (Bajpayee et al., 2000). In order to
avoid flyrock effect, protecting shelters should be constructed for the shotfirers (Bajpayee et al., 2003). While working with or near to electrical circuits, special care should be given and appropriate actions should be applied. Only authorized personnel can work with electric panels which also should be signed. Groundings should be periodically inspected and all electric cables should be safety covered and signed. Overhead or no-signed buried power lines should be avoided. Because of the dust in quarries, electric panels need systematic maintenance and inspection. 4.3 Risk control through corrective or protective actions In order to achieve more safe working conditions, appropriate actions should be applied. Listing all risks in declined risk factor, preventive or protective actions can be proposed, for unacceptable situations (R>200). In Table 4, risk control is applied for some non acceptable risks of a quarry. 5. RISK MONITORING AND PROCESS REVIEW In order to ensure that the risk control is effective, continuous monitoring is necessary. Systematic measurements of hazard agents (e.g. noise level, dust concentration) safety audits, performance indexes monitoring and medical tests are some methods that can provide signs of improvement. Additionally all process of Health and Safety management, should be evaluated in intervals. Risk assessment and effectiveness of risk control should be reviewed at least annually and new objectives should be applied, in order to achieve continuous improvement of working environment. 5. CONCLUSION Health and Safety management in quarries industry seems to be quite serious nowadays. However, robust methodology for risk control has not been applied and only individual actions are applied in some companies. Table 4. Example of risk control procedure Risk Ρ Η F R Risk Control Respiratory illness after crystalline silica exposure Hearing loss because of high noise levels Accident in the rotating parts of conveyor belts Accident while blasting (insufficient area evacuation Electrocution while working in electric circuits 6 9 8 432 Personal protective equipment, air filters, water spray sheeting 6 7 8 336 Noise insulation, personal protective equipment, health monitoring 5 9 6 270 Protective covers, signs 5 10 5 250 Safety guards, warning signs, sound signals before blasting 4 10 6 240 Authorized electricians, locked electric panels, personal protective equipment Fall of mezzanines 4 9 6 216 Robust construction, handrails, antislip floor, safety shoes
In this paper, a new procedure is proposed in order to achieve better working conditions. Analytical hazard identification through appropriate checklists, quantitative risk assessment and reactive risk monitoring is some of the main proposals. Through this methodology is getting obvious that heavy moving equipment, working machinery, electric circuits, explosive handling, noise and dust levels are the most critical hazards for Health and Safety of employees. However, best working practices can reveal solutions, reducing the risk for the personnel. Training, safety guarding, systematic maintenance and well design are some of the agents that can ensure risk control. Following the proposed methodology, Health and Safety management in quarries can be controlled and reviewed effectively, helping to achieve continuous improvement among this tough working environment. REFERENCES Association of Greek Mining Enterprises (2008). Information Bulletin of the activities Greek Mining Enterprises during 2007, Athens. Bajpayee, T. Rehak, T. Mowrey, G. Ingram, D. (2000). A Summary of Fatal Accidents Due to Flyrock and Lack of Blast Area Security in Surface Mining, 1989 to 1999, NIOSH Institute for the Economy of Constructions of Greece, 2002. Aggregates production in Greece, Weekly Bulletin of the Technical Chamber of Greece 2203, 136. NIOSH, Committee on Surface Workings US Department of State, (2002). Guidance to ensure safe use of large vehicles and earthmoving equipment in quarries, NIOSH Sapko, Μ. Rowland, J. Mainiero, R. Zlochower, I. (1999). «Chemical and physical factors that influence NOx production during blasting - exploratory study», NIOSH Wolcott, C. (2004). Bad Vibrations, Hand- Arm Vibration Exposure and HAVS Prevention, Quest Technologies INC Drivas, S. Zorba, K. Koukoulaki T. (1997). «Manual for risk assessment and risk control», ELINYAE, Athens ΕΚΑ- ELINYAE, (2004). «Manual for Occupational Health and Safety», Εκδόσεις E;LINYAE, Athens ELINYAE, (2003). «Hands in danger, HAV Syndrome», ELINYAE, Athens Kiritopoulos, K. Diamantas, B. (2004). «Risk management in projects», HSDM-E, Issue 378 Papadionisiou, N. (2001). «Safety in blasting», Athens SEPE, (2006). «Occupational accidents in Greece, 2000-2005», Athens Mines Inspection Agency of Greek Ministry of Development, www.ypan.gr Bajpayee, T. et al (2003). «Blasting Injuries in Surface Mining with Emphasis on Fly-rock and Blast Area Security», NIOSH Georgoulakis, K., Grigoroglou K. (2000). Occupational accidents in Mines and Quarries, Proced. of 3 rd Congress for the Mineral Wealth, 22-24 Nov. Athens, pp. 367-375.