Safety Health and Occupational Hazards - Essay Example

Safety Health and Occupational Hazards Occupational safety and heath is concerned with protecting the health and safety of people at their workplace. At a secondary level, it also deals with the health and welfare of the families of the workers. The International Labour Organisation (ILO) and the World Health Organisation (WHO) unitedly define Occupational Health as, "Occupational health should aim at: the promotion and maintenance of the highest degree of physical, mental and social well-being of workers in all occupations; the prevention amongst workers of departures from health caused by their working conditions; the protection of workers in their employment from risks resulting from factors adverse to health; the placing and maintenance of the worker in an occupational environment adapted to his physiological and psychological capabilities; and, to summarize, the adaptation of work to man and of each man to his job." There are several industrial processes which pose extreme risks to its workers. Welding, a major industrial process is concerned with joining metals by using a filler material. This filler material, known as the consumable is usually a coated electrode or wire. The process of melting this and the parent metal releases particulate fumes and gases, majority of which is produced from the consumable. The four most common welds are the tungsten inert gas (TIG), metal inert gas (MIG), metal active gas (MAG), and manual metal arc (MMA). (Pires et al, 2006) Some of these emissions are toxic in nature which can prove hazardous on prolonged exposure. Presently, 1-2% of workers from different professional backgrounds (some 3 million persons) are subjected to welding fume and gas action (Pires, 1996). In confined spaces, welding can be deadly, as without proper ventilation, toxic fumes and gases can be much more intense, and possibly over the respective limits for toxic substances. . In the recent years, occupational health hazards have formed the locus of intense academic study and research. The harmful effects of welding fumes have also been studied in great detail. The potency of the gas emissions depends on a number of factors like the nature of electrodes employed, the type of welding, filter metals, and also the ventilation facilities in the welding area. The emissions include metal oxide particles, gases, solvents, coatings and residues. Most of these are air borne and thus are constantly inhaled by workers. Harmful Effects of different Metals Compounds The welding fumes also contain compounds of metals like hexavalent chromium, nickel, manganese, zinc etc. It is difficult to find out the respective effects of different metals as most of tem are interrelated. (Hilton & Plumridge, 1991). But technological advancements have made it possible to draw a rough idea about each element's effect on the human body. It has been medically proven than nickel and chromium cause nausea, headaches, dizziness, thirst, fever, muscle ache, chest soreness and respiratory illnesses on short term exposure. Short term usually implies 12-24 hours, and these short term effects are generic for nearly all emissions. These effects also include gastrointestinal ailments, such as appetite loss, vomiting, cramps, and slow digestion. Nickel and Chromium fumes can also cause skin rashness and dermatitis. Nickel is also known to cause asthma, while chromium may cause sinusitis. The chronic, long term effects of fumes containing nickel and chromium still remain ambiguous, but there are vague indications that they might be carcinogenic in nature i.e. they might act as cancer causing agents. The National Institute for Occupational Safety and Health has declared that some forms of hexavalent chromium, nickel and their inorganic compounds be considered carcinogenic.(American Welding Society, 2003) As a matter of fact, the long term effects of welding smoke in general remain disputes. Though there are reasons to believe that prolonged exposure might lead to immunosuppression, lung cancer development, neurotoxicity, skin damage, reproductive disorders, studies still haven't been able to medically prove this hypothesis. Some metal compounds can be especially dangerous in short term durations. Cadmium is one such metal, which can prove fatal even on short term exposure. Cadmium is employed as an alloying element and as a rust preventive coating on steel. High levels of this metal can cause acute lung irritation and pulmonary oedema, and in extreme cases, death. Its long term effects are equally dangerous- it can cause emphysema- a disease that reduces the oxygen absorbing capacity of the lungs, usually associated with chronic smoking (HSE, 2004). Cadmium exposure can also lead to kidney ailments in the long run. Besides that, Cadmium is classified by OSHA, NIOSH, and EPA as a potential human carcinogen. Manganese is another metal compound which is extensively used in welding to produce steel. Studies have shown that exposure to higher levels of airborne manganese can have grave consequences. Under healthy circumstances, manganese is present as an essential nutrient in the body. Excess of dietary manganese can be excreted by a functional excretory system. But inhaled manganese poses greater threat as it bypasses the normal regulating mechanism of the body. Inhaled manganese gets accumulated in the body and can adversely affect the kidneys, lung and the central nervous system. In males, excess of manganese can also lead to infertility. Exposure to lower levels of manganese (1 mg/m3) can lead to a form of disease called Manganism, which is very similar to Parkinson's. Manganism is caused by damage to the basal ganaglia present in the brain. A person suffering from manganism may experience characteristic Parkinsonian symptoms tremors, slowness of movement, muscle rigidity, and poor balance, arm and leg stiffness, difficulty negotiating turns, and sudden freezing spells. Prolonged exposure to high levels of manganese can also lead to progressive Parkinson's (Cook et al, 1974). But unlike the normal Parkinson's, welding induced Parkinson's and manganism do not respond to Levopada, the drug traditionally used to treat Parkinson's. (Huang et al. 1993) Besides Manganism, manganese in higher doses can also cause decreased motor skills, diminishing intellectual capacity, increased tremors, and memory loss. In addition to manganese, zinc is also used extensively in welding purposes. While welding or cutting of metals, zinc can react with the oxygen present in air to form zinc oxide (ZnO). This compound, in higher concentrations is known to cause an ailment called Metal Fume Fever, which is an acute allergic condition. The symptoms of this disease are very non specific in nature and are similar to symptoms of influenza like fever, chills, nausea, headache, fatigue, muscle aches, and joint pains. These symptoms usually surface about 6 to 24 hours after exposure, and the patient recovers within 24 to 48 hours without any sort of medical aid (NIOSH, 2002). A sweet or metallic taste in the mouth coupled with extreme thirst is also experience during metal fume fever. This sensation distorts the taste of food, and might lead to hoarseness in the throat. The symptoms of this fever are more likely to be experienced during a period away from work. After the initial symptoms, the patient is most likely to experience mild fever, which subsides in a few hours. Continuous and prolonged exposure to oxides of zinc leads to repeated attacks of metal fume fever. Though the details about how metal fume fever affects the body are still being researched, the most possible theory is as follows. On inhalation of zinc oxide, an immune reaction occurs in the body, to prevent damage to the cells of the respiratory tract. This leads to modification in the processes of the lungs, which ultimately, through a series of complicated mechanisms, causes flu like symptoms (Kaye et al, 2002). Diagnosis of this sort of fever is extremely difficult as the symptoms are very non specific and also transitory. Chest X- rays also prove inconclusive. It can be confused for a lot of other diseases like acute bronchitis etc. also, after consistent exposure; people might develop a certain level of tolerance to it, though this tolerance is also temporary in nature. If and when diagnosed, the treatment involves mostly bed rest and symptomatic relief. Like other chemical compounds, the long term effects of zinc are still uncertain. Though the metals mentioned above are the major elements present in the emissions, minute quantities of some other chemical compounds like beryllium, lead and mercury are also present. Beryllium, if present in alarmingly high levels can lead to chemical pneumonia. Over a longer period of time, it can also cause shortness of breath, chronic cough, considerable weight loss and perennial fatigue (OSHA, 1996). Mercury is generally used to prevent rust formation. Excess of mercury in welding fumes can lead to digestive problems like stomach pain, diarrhoea, besides causing kidney and respiratory damage. Lead, like zinc, forms its oxides when it combines with the oxygen present in air. This reaction is facilitated by the high temperatures generated by the welding process. Inhalation of lead oxide fumes and other lead compounds can cause lead poisoning. Symptoms of lead poisoning include metallic taste in the mouth, loss of appetite, nausea, abdominal cramps, and insomnia. Over prolonged exposure, lead is known to cause anaemia and muscle fatigue. It also affects the brain, central nervous system, circulatory system, reproductive system and the kidneys (Antonini, 1998) As has been mentioned earlier, the emissions released in the welding process are invariably gaseous in nature. Thus, they also contain a number of lethal gases, which coupled with the other chemical compounds, greatly increase its potency. Toxic gases like ozone, carbon monoxide and nitrogen oxide constitute the gaseous component of these emissions. Carbon monoxide can be fatal as it reduces the oxygen carrying capacity of the blood, excess of both nitrogen oxide and ozone can cause pulmonary oedema among other effects. Preventive Measures Thus, we see that welding fumes can be extremely dangerous in nature. They contain a number of metal and gaseous chemical compounds, which often react with each other to heighten the effect on the human body. Over the recent years, efforts have been made to prevent the occurrence of these occupational hazards by inventing protective equipment and regulating the permissible concentrations of the lethal compounds. In the United Kingdom, these limits are known as Workplace Exposure Limits (WEL's). They are for use with the Control of Substances Hazardous to Health Regulation and are published annually in EH/40 from the Health and Safety Executive. They define the permissible levels of several hazardous emissions. Similarly, every country has its own regulating mechanism (HSE, 1992). In the United States of America, the Occupational Safety and Health Administration (OSHA) negotiates the safety rules pertaining to welding. In addition to the declaring safe limits for emission particles, these agencies also certify the welding organization on the basis if certain well defined parameters. These include certifying proper ventilation at the work place, instalment of necessary safety measures, presence of adequate medical aid etc. For example, Occupational Safety and Health Administration (OSHA) recommends the use of engineering or work practice controls to manage or eliminate hazards to the greatest extent possible (OSHA, 2007). Thus, every welding factory has to undergo a rigorous screening process until it is deemed fit and officially recognized by the government of that respective country. Personal Protective Equipment Personal Protective Equipment (PPE) is a set of protective gears required by welders to protect themselves against hazards such as burns, sparks, electric shock and radiation. They are used as a secondary line of safety measures, the primary being engineering and administrative tools to prevent as much danger as is possible. Welding releases a number of harmful radiations besides producing sparks and minor fires. Under such circumstances, there is great danger of a fire breaking out. The PPE are designed to minimize such risks and to protect the workers against them. PPE forms an integral part of the safety mechanisms devised to ensure occupational health and welfare. It is imperative for all welding organizations to have and maintain the necessary levels of PPE. The official standards for these equipments differ from country to country, with their respective labour agencies regulating absolute safety standards (Farhang, 2000). The PPE's for every welding firm are chosen specifically after assessing the different plausible hazards. The most basic form of equipment includes a face shield or a helmet, safety eye wear, filters for protection against harmful radiation, ear protectors, respiratory protective equipment, protective hand gloves and footwear, and safe clothing. The PPE's are chosen according to the specific welding process being carried out. There are strict regulations regarding their production and maintenance. For example, a welding helmet must be opaque to light and resistant to impact, heat and electricity and its outer covering should be made of polycarbonate plastic which protects from UV radiation, impact and scratches. Similarly filters for protection against welding radiation range from 1.2-16, and are chosen depending upon the energy released in a specific process (HSE, 2004). Thus, one can infer that PPE's reduce the risks involved in welding processes. Regulation of levels of hazardous elements in emissions also ensures safety of the welders. The replacement of excessively hazardous substances with less hazardous ones can also help a great deal in preventing any unwanted health complications like, using cadmium-free silver solders and asbestos-free electrodes, gloves, and hot pads, and using welding rods which produces lesser fumes (Balchin, 1983). Exhaust ventilation and air monitoring must be provided at the workplace, which would successfully dispel the toxic emissions. At the same time, it must be ensured that welding is not carried out in a confined space, there must be enough room for ventilation. Further, the workers must be allowed to take frequent breaks from work, to avoid prolonged exposure to the harmful effusions. Regular medical check ups must be arranged for, and if symptoms are detected in any worker, all efforts must be made to endure that he or she does not come in contact with radiation in the near future. If all the aforementioned steps are taken, relative amount of occupational safety can be guaranteed to the workers. Bibliography Antonini, JM. 1998. "How welding fumes affect the welder". Welding Journal ;77:55-59 American Welding Society, 2003. "Fumes and Gases in the Welding Environment " Viewed 04 May, 2009 Balchin, N. 1993. "Health and Safety in Welding and Allied Processes" Welding Institute 198 Cook DG et al. 1974. "Chronic manganese intoxication" Arch Neurol ;30:59-64. Farhang, A. et al, 2000. "Comfort of Personal Protective Equipment" Science Direct, 26-3 Health and Safety Executive, 2004. "Cadmium and You". Viewed 05 May 2009. http://www.hse.gov.uk/pubns/indg391.pdf Health and Safety Executive. " A Short Guide to the Personal Protective Equipment at Work Regulations 1992". Viewed 04 May 2009. < http://www.hse.gov.uk/pubns/indg174.pdf> Hilton DE, Plumridge PN. 1991. "Particulate fume generation during GMAW and GTAW". Welding & Metal Fabrication :62:555-560 Huang CC, et al. 1993. "Progression after chronic manganese exposure". Neurology ;43:1479- 1483. Kaye P et al. 2002. " Metal fume fever: a case report and review of the literature." Emerg Med J; 19:268-269. National Institute for Occupational Safety and Health (NIOSH). 2002. "Criteria for Recommended Standard: Occupational Exposure to Chromium (VI)"), NIOSH 76-129 National Institute for Occupational Safety and Health.2004. "Criteria for a Recommended Standard - Occupational Exposure to Zinc Oxide", NIOSH 76-104 Occupational Safety and Health Administration, 2007. "Personal Protective Equipment Payment Standards". Viewed 05 May 2009. < http://www.osha.gov/Publications/PPE-factsheet- final.pdf> Occupational Safety and Health Administration, 1996. "Welding Health Hazards" Viewed 06 May 2009. < http://www.osha.gov/SLTC/weldingcuttingbrazing/recognition.html> Pires, I. 2006. "Fume Emissions During Gas Metal Arc Welding", Toxicological and Environmental Chemistry 88(3): 385-394 Pires I 1996. " Analysis of the influence of shielding gas mixtures on features of MIG/MAG" MSc Thesis, Lisbon Technical University. Read More