Hazards of Aluminium Welding Fumes - Research Paper Example

 OCCUPATIONAL HEALTH AND SAFETY MONITORING, ANALYSIS AND CONTROL OF TOXIC SUBSTANCE IN THE WORKPLACE HAZARDS OF ALUMINIUM WELDING FUME INTRODUCTION More than 65,000 chemicals are currently in use in U.K with which human beings come into constant contact. Many of these chemicals are harmful and pose a serious health hazard. Numerous chemicals have been designated as hazardous to biological system and these chemicals pose an occupational health hazard to workers who are constantly in contact with them. These chemicals are often toxic, mutagenic/carcinogenic, causing serious diseases like Cancer and disabilities of various kinds. Even children born to women working in nickel refinery have been found to have Genital malformations. This offers understanding of the seriousness of occupational hazards due to chemicals (Vaktskjold, 2006). The biggest problem here is that the diseases do not develop immediately but appear after a few years of exposure. The impact of pollution at workplace on productivity has been well investigated. Studies on the impact of pollution at work environment in productivity reveal a tendency of reduction in the economic activity (Marrewijk, 2005). “Sick building Syndrome” (SBS) and ‘Building related illness’ (BRI) gives rise to employee complaints such as headaches, dizziness, disorientation, fatigue, ear, eye and throat irritations. ALUMINIUM WELDING FUME The world demand for high-speed ferries and LNG tanks is being met with an increase in Aluminium welding and casting production. This has introduced a new health hazard to the Aluminium welders and ways are being probed to protect the welders against the Aluminium fumes. In the U.K, the Control of Substances Hazardous to Health (COSHH) regulations stipulates that the occupational expose limit for Aluminium fume should not exceed 5mg\m exp 3 of air. Aluminium fumes during welding also generate quantities of ozone gas, which can cause nausea (Rabin, 1997) and unconsciousness. Welding is a process in which metal or other thermoplastic materials are joined together by the application of heat or pore sure or both. Electric welding was introduced in 1940s. Aluminium welding has been in prominence since 1970. There are several types of welding like Arc welding and Manual metal arc is a common process where the workers are exposed to the fumes. Carbon arc, Cold welding, Electron beam welding, Flux core arc welding, Gas welding, Gas metal arc welding, Gas tungsten arc welding, Shielded metal arc welding, Plasma arc welding, Laser beam welding are the other welding processes where workers are exposed to metal fumes. The welding workers have a high exposure of metal fumes and the exposure depends on place, confined space, workshop or open air. The metal fumes depend on not only the Aluminium but also the process involved, which may produce gases like acetylene, carbon monoxide, oxides of nitrogen, ozone, phosgene and tungsten. The metal fumes primarily enter the human system by inhalation route namely Respiration.. The deposition of these inhaled metallic particles is influenced by its physical and chemical properties and a variety of host factors. In the lungs, these particles produce a variety of reactions depending on the concentration, duration of the exposure of the particles, and degree of exposure. All Metallic particles greater than 10 are deposited on the Mucous membrane in the nose and pharynx. Particles between 3m and 10 m are deposited throughout the trachea of the lungs. Particles less than 3m are deposited in the alveoli and cause serious hazards. These particles have a fair chance of being carried into the blood stream and cause Hepatotoxicity and Nephrotoxicity. SAMPLING METHODS Hazards of Aluminium fumes have been well documented in various scientific journals. The health hazard assessment is done by sampling and analysis. Sampling has been well prescribed by the Draft British Standard (DD54) for breathing zone and background samples. Chemical analysis techniques for milligram amounts of fume obtained are outlined in DD54; part I.(Moreton,1982).The metallic particles are classified as inhalable, respirable, sub-micron, thoracic and fractionates according to the size of the particles. The sampling technique and devise depends on thus, the size of the particles. For sampling and assessing inhalable particles, a flow rate of 4 litres of air per minute with a 25 mm filter is recommended. For assessing respirable particles, a flow rate of 2 litres per minute with 25mm filter is recommended. For sub-micron particulate assessment, a flow rate of 1.7 litres per minute with 37 mm filter is recommended. For the assessment of thoracic and fractionates a 9 litre flow rate with 37 mm filter is ideal. The sample can be assessed by gravimetric analysis. Passive- diffusive air samplers provide a simple, reliable, and economical method for air sampling for personal sampling. Mandatory surveillance programmes of the working atmosphere, measurements of fluorides and particulates are annually carried out in the aluminium industry. Potroom workers are randomly selected to wear personal samplers for 8hour shifts at different intervals. Usually 10-20 measurements are carried out in a year. Time weighted mean estimates of exposure to total fluorides and particulates in selected job categories are calculated representing the exposure during the past years. Various analytical methods have been developed to determine aluminium in biological samples. Graphite furnace atomic-absorption spectrometry (GF-AAS) and inductively coupled plasma - atomic-emission spectrometry (ICP-AES) have been the most frequently used methods. Contamination of the samples with aluminium from air, vessels or reagents during sampling and preparation could cause errors in assessment. HEALTH HAZARDS OF ALUMINIUM FUMES Aluminium work related Asthma has been established by characteristic patterns of repeated peak flow measurements supported by changes in methacholine responsiveness in workers with work related asthma (Konyerud, 1994). A recent study by keith Harrison of the Queens land Fertility group, Australia has proved the testicular toxicity of such Chemicals in male workers. Studies have also proved that exposure of workers to these metal fumes aged between 20-64, admitted to 11 hospitals in England during the period between 1996-1999, caused health hazards and is a classic case of occupational hazard of metal fume exposure (Palmer, 2003). Further studies on 27 welders with long-term exposure to these metal fumes revealed a reversible increase in the risk of Pneumonia. In the sputum, cell counts, soluble levels of the metal, levels of Interleukin-8, tumour necrosis factor-, myeloperoxidase, metalloproteinase –9, Immunoglobulin (Ig)A,  2-macroglobulin and unsaturated metal binding capacity were analyzed and in the blood samples, evidence of neutrophil activation and IgG pneumococcal antibodies were analyzed. The studies concluded that the local inflammatory response was affected by chronic exposure (Palmer,2006). All welding workers thus, are exposed to acute or chronic respiratory disease. Welding fumes cause lung function impairment, obstructive and restrictive lung disease, cough, dyspnea, rhinitis, asthma and even carcinoma of the lungs. These welding workers also suffer from eye irritation, photo keratitis, cataract, skin irritation, erythema, pterygium, non-melanocytic skin cancer and infertility (sultan A, 2003). In a recent study of seven Swedish foundries where workers were exposed to strong Aluminium fumes, the exposure and concentration of the Aluminium in vapours were determined as daily, time-weighted averages (TWAs). The Geometric mean (GM) of the total dust was 5.1mg\m3 But a few high exposure levels of GM 8mg\m3 was reported in furnace workers. The role of Aluminium fumes in causing occupational asthma was convincingly substantiated by Vendenplas.et.al,(1998).The case report was of a 32 year old man who welded aluminium pieces. After 4 years of intermittent exposure, he developed tight chest with wheezing on days he welded aluminium . Asthmatic symptoms started 1-4 hours after getting exposed to the aluminium fumes. Baseline spiromertic measurements showed a forced expiratory volume of 4.38L (Vendenplas, 1998). Further studies proved that aluminium fumes stimulated an asthmatic reaction in chronically exposed cases. Incidentally, a severe form of clinical asthma or bronchial hyper responsiveness has been reported in workers exposed to soldering aluminium (Hjortsberg,1986). The recent studies on thyroid functions of the welders exposed to metal fumes have thrown light on the seriousness of the exposure hazard. (Zaidi,2001).Studies were conducted on 20 healthy male workers with an average occupational exposure of 13-18 years .Serum analysis for serum thyrotropin (TSH) was done by solid phase immunoradiometric assay( TSH/IRMA ). Serum total T3 and T4 were measured by radioimmunoassay( RIA ). Statistical analysis was done using student’s ‘t’ test. The levels of TSH 7.34 ( against the normal 0.81-3.2 IU/ml) and 6.56 respectively indicated thyroid disorders. The prevalence of Muscloskeletal symptoms has been reported in workers in aluminium industry Kezunovic,2004). A prevalence of one year of the symptoms in aluminium potroom workers was studied in correlation with exposure. The findings asserted a positive correlation of the exposure and Muscloskeletal symptoms in workers. Increased nitric oxide in exhaled air has been investigated as an early marker of asthma in non-smoking Aluminium potroom workers recently( Lund et.al,2000). RISK ASSESSMENT OF THE HAZARD BASED ON LEGISLATIONS COSHH classifies a group of substances, which on Breathing in, causes occupational Asthma and other respiratory disorders. There are called ‘Respiratory Sensitizers’ at work. The COSHH guidelines tell about the symptoms and the legal duties of the employers to protect their employers. As discussed, more than 65,000 chemicals are currently in use in U.K with which human beings come into constant contact. Many of these chemicals are harmful and pose a serious health hazard. Numerous chemicals have been designated as hazardous to biological system and these chemicals pose an occupational health hazard to workers who are constantly in contact with them. These chemicals are often toxic, mutagenic/carcinogenic, causing serious diseases like Cancer and disabilities of various kinds. COSHH standards demand that all chemicals must be labeled with the identity of the contents and have hazard warnings. The labels should be in English and employees must be able to cross-reference the label to the MSDS (Material Safety Data Sheet). Employees should be trained in methods used to detect the presence or release of hazardous chemicals, the physical problems caused by them and the ways to protect themselves by way of protective clothing and masks. The potential danger the chemicals pose on reproductive health, their carcinogenic effect, mutagenic effect makes it important for the Organizations to inform the employees on the chemical hazards. The International Labour Organization’s “International Occupational safety and Health Information Center (CIS)” in its list of chemicals puts Aluminium in hazard list. The hazard includes flammable and explosive properties of the chemical and the property of dispersed particles to be inhaled, ingested and deposited on eyes and skin. The chemical falls in UN hazard class: 4.3. The Occupational exposure limits has been assigned as 5mg/m3. The CIS also gives information about its effect on lungs and nervous system. In a circular numbered 71/2002, The Health and safety Executive (HSE) published revised COSHH (the control of substances hazardous to Health) regulations. This COSHH 2002 regulations came into force from 21 November for hazardous substances and includes control measures for hazardous substances. COSHH 2002 spells out much more clearly on risk assessment than COSHH 1999. The risk assessment includes the properties of the chemical, health effects, the exposure limits, preventive and control measures, health surveillance, monitoring and other additional information needed. The EH40 ,on occupation Exposure limits, published by HSE books, EH54 on Assessment of exposure to fume from welding and allied and processes, EH55 on the control of exposure to fume from welding, provide good data required for risk assessment like occupational exposure limit (OE). The supplement to the control of substance hazardous to Health Regulations 2002 addresses the respiratory hazards in discussion. According to these regulations, every employer should ensure the prevention of employee’s exposure or adequately control where in not practicable reasons to prevent. Personal protective equipment (PPE) must be used only as a last resort, in addition to control measures. When RPE (Respiratory Equipment) is used to control exposure, the correct equipment and training are to be ensured. Appendix I of the supplement gives guidelines on Respiratory protective Equipment selection and training. Health surveillance under COSHH Regulations 2002, Requires Health surveillance programmes where the exposure of the employee to a substance hazardous to health is such that identifiable disease or adverse health affect may be related to the exposure; There is a reasonable likelihood that the disease or effect may occur under the particular conditions of the work and there are valid techniques for detecting indications of the disease or effect .(Regulation 11). University college, London, occupational Health Service (OHS) provides health surveillance for relevant Occupational groups. The Occupational groups currently work with Respiratory Sensitisers and laboratory allergens(LAA). COSHH stipulates that prevention and adequate control of the exposure should be done either by stopping using the sensitiser (Chemical) and replacing it by less harmful substance or segregating the workplace or provide local exhaust Ventilation or by use of Respiratory protective instrument (RPE). That is to say that only where prevention of exposure is not possible , adequately controlled exposure is recommended (www.COSHH.com).Adequate control means Application of the eight principles of good practice as in shedule 2a of COSHH, not exceeding workplace exposure limit (WEL) and for substances Causing Cancer, Asthma and serious damages, reduction in exposure levels to practically reasonable levels (EH40, 2005).Control measures must be put into use by the employees and it is the duty of the employer to see the implementation according to COSHH. Under COSHH, the employers should measure the concentration of hazardous substances in the air breathed in by the workers. As per Shedule 5 of the COSHH, air monitoring should be done in the breathing zone, i.e. at the workplace where the worker is exposed to aluminum fumes. RECOMMENDATIONS BASED ON COSHH GUIDELINES Reducing unsafe conditions is the first component of prevention of occupational hazards. Removal of physical hazards by job designs, identifying hazards by checklist procedures helps reduce unsafe conditions. The remedial measures can be simple like protective clothing, welding masks or designing job properly with hazard watch supervisors and job rotation. . For those indirectly exposed Extraction fans and LEV with filters serve the purpose of protection. For the Welders who are directly exposed P2 - P3 masks, Air Fed masks serve the purpose of protection. Safety glass saved the eye sight of an electric arc flash worker on 13 June 2005. The accident was so serious that the protective glass was covered with molten metal and fuse filler which would have blinded him completely. (www.occupationalhazards.com ) and Safety training programs. Safety Programs The fact that the law demands a safe work environment triggers a ‘Safety Program’ in every Organization. Organizations with Safety Programs implement COSHH Standards by various activities. 1. Safety Awareness Promotion: Most organizations have a Safety Awareness Programme that includes lectures, commercially produced films, Video shows and pamphlets, which teach employees safe work procedures. They also create an awareness on safety hazards that occur on account of the non-compliance of Safety norms. 2. Proactive Safety Training Program: Safety training programs include, Accident prevention techniques, Hazardous materials awareness and Emergency procedures training. ENFORCING SAFETY RULES Safety rules and regulations are communicated through supervisors, bulletin boards, employee handbooks and signs attached to machines/equipments. Regular safety meetings refer to the use of safety devices, proper work procedures, good housekeeping procedures, complying with accident-injury reporting, safety clothing and avoiding carelessness. It is true that discipline makes employees to work safely. But it is voluntary willingness from the employee that will last for a long period. All the employee safety programs aim at this employee involvement in the safety aspects of the organization. COSHH requirements demand that organizations with eleven or more employees should maintain records of work related occupational hazards. A recordable case is an injury or illness that results in death, days away from duty, restricted work or transfer to another job due to disability, or medical treatment beyond first aid (Bohlander, 2004). CONCLUSION Safety starts with management commitment. For example, Dupont’s accident rate is lower than the other chemical industries as a whole. Its good safety record is due to the organizational commitment to safety. Each morning at the Dupont Polyester and Nylon plant, the directors and his assistants meet at 8.45 to review the past 24 hours. The first matter for discussion is safety and not production. Only after examination of reports of accidents and near misses, they look into production for the day (Dessler, 2003).In U.S.A., Safety program at a Missoure, ABB Business Services plant resulted in 80% reduction of accident cases and $560,000 recorded as profit. Compensation costs for accidents have soared sky high. It should be recognized that effective cost management on compensations starts before the occupational accidents and not after. Occupational Safety and Health Programs are an important component of organizations. Occupational hazards are numerous and expensive to the organizations. There are laws that safeguard the employee’s physical and emotional well-being. As per Herzberg’s theory, working condition which assures safety is a factor of motivation in organizations. A cost-oriented manager understands the importance of avoiding accidents in his organization. Costs associated with leave due to illness, disability compensations and alternate skilled employee placement are huge and have a negative impact on employee morale.75 million working days are lost because of on-job-hazards. $50 billion are given as compensation for injuries and deaths in organizations. $50 billion is spent on indirect costs like replacement, training and so on (Bohlander, 2004). Organizations should ensure a safe work environment which protects employees from physical hazards and unhealthy situations. This can be achieved by Safety and Health Programmes which strives to preserve the physical and emotional well-being of the employees. This is important because employees are the Human Resources of an organization who contribute towards organizational success. REFERENCE Ahmed Zaidi et.al , Preliminary studies on Thyroid Function in Welders; ‘J. Occup. Health, 43:90-91,2001. Bohlander, Snell, Thomson, “Managing Human Resources’, South- western, International Student Edition, 2004. Charles Van Marrewijk, “Geographical economics and the role of pollution on location, journal of Environmental Economics”, Vol.111, No.3, ICFAI university press, India, Aug 2005. Gary Dessler, “Human Resource Management”, 9th editions, Prentice Hall of India, 2004. J. Donald Miller, “Screening and monitoring; Tools of prevention” ,Journal of occupational and environmental medicine.28(8);544-546 Kathlyn Reed, “Concepts of Occupational Therapy”,4th edition, Lippincott Williams-Wilkins,1999 Kongerud. 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William E. et.al ,”Conference on Medical screening and Biological monitoring for the effects of exposure in the work place .Part 2”,Journal of occupational medicine;Volume.28(10);901-1126,Aug1986. www.ccohs.ca www.iosh.co.uk www.occupationalhazards.com www.puresafety.com www.COSHH.com Read More