Wednesday, October 23, 2019

Wood is an important worldwide renewable natural resource.

Chapter 1: Introduction1.0 IntroductionWood is an of import worldwide renewable natural resource. Forests comprise about one-third of the Earth ‘s entire land mass ( 3.4 million km? ) . There are an estimated 12,000 species of trees, each bring forthing a characteristic type of wood. ( International Agency for Research on Cancer, 1995 ) Wood based industry in Malaysia comprises four major bomber sectors. There are sawn timber veneer and panel merchandises, which include plyboard, and other reconstituted panel merchandises such as particleboard, hardboard, or fibreboards, moldings, builders joinery and woodworking, furniture and furniture constituents. The industry is preponderantly owned by Malayan and it is estimated that 80 per cent to 90 per cent of the companies comprise little and average sized constitutions. In Malaysia, furniture makers produce a broad scope of furniture from dining room, sleeping room, kitchen, office, occasional, living room, upholstered furniture or couch, outdoor and garden furniture. In Malaysia wood based industry for furniture and fixtures public presentation, furniture industry is extremely export-oriented with over 90 per cent of its production exported. Malaysia presently ranked as the ten percent largest exporter of furniture in the universe and 2nd in Asia after the People ‘s Republic of China, with exports to more than 160 states. In 2008, exports of wooden furniture amounted to RM 6.8 billion. The chief export finishs were the United States of America, Japan and Australia. The export value is expected to make RM 10 billion by 2010.More than 80 per cent of the furniture exported from kitchen furniture, sleeping room furniture, upholstered with wooden frame, and office furniture are made from gum elastic wood, or Hevea Brasiliensis which is a light colored, medium hardwood popularly called â€Å"Malaysian Oak.† As the demand for exports of furniture additions, so does the production rate additions, and in Malaysia furniture industry, the wellness jeopardy associated with wood dust have yet receive coverage particularly with concern to the wellness of its workers and to the environmental air quality environing it. Wood dust is defined as any wood atoms originating from the processing or handling of forests. Wood dust is generated when lumber is processed, such as when it is chipped, sawed, turned, drilled, or sanded. ( Occupational Safety Health Administration, 1989 ) . Wood dust is normally measured as air-borne atom dust concentration, by atom size distribution, by type of wood, and by other features of wood ( International Agency Research Cancer 1995 ) . Wood dust is used to fix wood coal, as an absorbent for glyceryl trinitrate, as a filler in plastics, and in linoleum and poster board ( Radian. , 1991 ) . Another commercial usage for wood dust is in wood composts ( Weber et al. , 1993 ) .Wood dust occurs in the environment in countries where machinery or tools are used to cut or determine wood. No flash-point informations are available for wood dust. However, wood dust is flammable and will light in the environment. It may show a strong to severe detonation jeopardy if a dust cloud contacts an ignition beginning. Wood dust is stable under normal laboratory conditions. Exposure to wood dust occurs to persons utilize machineries to cut or determine wood. Deposition within the air passages depend on the size, form, and the denseness of the dust atoms and the turbulency and speed of the air flow. ( International Agency Research Cancer 1981 ) . Use of manus held electric smoothers are identified as a peculiarly dusty, which would take to exposure to wood dust. Wood dust concentrations vary with type of dust extraction, sum of wood removed and type of smoother. ( Thorpe and Brown, 1994 ) . Different type of wood will besides bring forth different sum of dust. Hardwood and deal are different in the physical chemical belongingss that leads to the different in the sum of wood produced.1.1 Significance of surveyThe significances of this survey are:To detect the degree of safety and wellness consciousness among the workers of wood working to wood dust.To propose a extenuation attack to minimise the exposure to wood dust through technology control and good ho use maintaining.1.2 Aims of the surveyTo measure the exposure of wood dust concentrations on sanding and routing wood procedures in a Rubber wood furniture mill.To suggest appropriate steps to cut down wood dust emanation in the furniture mill.1.3 Problem statementWood dust is known to be a human carcinogens based on surveies done by Research workers from the Department of Health and Human Services in United States and American Conference of Governmental Industrial Hygienists ( ACGIH ) proposed 1 mg/m? of eight hr Time Weighted Average value for all wood dust species. In general, exposure to inordinate sum of wood dust is considered to hold an irritant consequence on eyes, nose, and pharynx in add-on to pneumonic map damage. Therefore, the intent of holding a monitoring plan is to measure and supervise the degree of exposure of wood dust to the environing environment and particularly on workers that have historical background or old record of holding any related wellness jeopardies to wood dust.1.4 HypothesissThe hypotheses in this survey are:Entire wood dust concentration and Respirable dust concentration on sanding and routing procedures in furniture industry falls into the standard bound as proposed in Occupational Safety and Health Act 1994 by Department of Occupational Safety and Health Malaysia ( DOSH Malaysia ) which is 1 mg/m3.Furniture mill have their ain safety steps taken to cut down the sum of dust emitted by the usage of cyclones and Personal Protective Equipment wore on workers.1.5 Case survey backgroundThe location for this survey is in Muar, Malaysia one of the most concentrated part for furniture fabrication industry and production of Rubberwood furniture ‘s. The mill is situated a t the 4th Lot in Industrial Zone Parit Jamil, where Rubber wood furniture merchandises such as table leg, bed stations, light base are made. The mill itself has 100 workers, chiefly are from Nepal, Bangladesh and Myanmar.1.6 Limitation of surveyQuestionnaire signifiers that have been distributed are chiefly done in Bahasa Malaysia due to linguistic communication restraint among workers from foreign states such as Bangladesh, Myanmar, Vietnam and Nepal workers in the mill.Chapter 2: LITERATURE REVIEW2.0 IntroductionForests cover about tierce of the universe the Earth ‘s entire land country, about 3.4 million km2.There are 3.5 thousand million M3 of the tree biomass is harvested, about half which is used as fuel, the remainder as sawn wood, pulpwood, and more. ( Gichner. , 1995 ) . There are an estimated 12, 000 species of trees, each bring forthing a characteristic types of wood.2.1 Definition of wood dustOccupational Safety and Health 1989 stated that wood dust is defined as a ny wood atoms originating from the processing or handling of forests. Wood dust is generated when lumber is processed such as when it is chipped, sawed, turned, drilled or sanded. Harmonizing to IARC 1995, Wood dust is known as a light brown or tan hempen pulverization. It has a specific gravitation of 0.56. Most tree species are deciduous tree, hardwood chiefly angiosperms. Merely about 800 species known as deal are Gymnosperms, or cone-bearing species, . ( Bauch. , 1975 )Type of woodThe footings â€Å"hardwood† and â€Å"softwood† does non needfully mention to the hardness of the wood, but to the species. Hardwood is by and large denser compared to softwood, where the denseness varies well within each group. The scientific and common names of some deal and hardwood are compiled in table 1 ( Vaucher. , 1986 ) . Wood dust is besides characterized by its wet content: Dry wood ( moisture content less than approximately 15-20 % ) is less elastic than moist ( green ) wood, and woodworking operations with dry wood consequence in a larger volume of entire dust and a higher per centum of inhalable dust atoms ( Hinds. , 1988 ) .2.2 Occupational exposure to wood dust.Dust exposure occurs in a big figure of woodworking industries, where dust arises from scratch, grinding, screening or blending. Traditionally, wood dust is considered as a nuisance dust, and its inauspicious effects on open workers have merely received attending. ( W.K.Liu et al. , 1985 ) . Harmonizing to Jones and Smith 1986, in this century, veneer- and plastic covered hardboard and fiber-board panels have been used intensively for the industry of cabinets, table tops and similar and hardwood merchandises. Solid hardwoods and hardwood-veneered panels are used for high-quality furniture because of the attractive form formed by their grains. Wood dust exposure occurs in chiefly as an occupational exposure in some industries and businesss. The partial list of open workers includes lumbermans ; sawmill workers, workers involved in the industry of plyboard and other boards, wooden furniture workers and cabinet shapers, workers in the industry of other wood merchandises, and carpenters and joiners in the building industry. Exposure to wood dust has long been associated with a assortment of inauspicious wellness effects, including dermatitis, allergic respiratory effects, mucosal and non allergic respiratory effects, and malignant neoplastic disease. Other symptoms associated with wood dust exposure include oculus annoyance, rhinal waterlessness and obstructor, prolonged colds, and frequent concerns. The type and degree of exposure to wood dust can be described in several ways. A first of import feature is the type of wood ( hardwood, deal ) and tropical wood, or other wood species. Hardwoods are deciduous trees such as oak, beech, calcium hydroxide, ash, birch, poplar, elm, or cherry trees. Softwood is cone-bearing trees, such as fir, spruce or pine. Wood is besides characterized by its wet content, which depends both on the species and on the freshness of the wood. The concentration of airborne dust is by and large measured in mg/m? with standard methods. ( IARC, 1995 ) The atom size is besides an of import parametric quantity, because the deposition form in human upper and lower air-ways partially depends on the atom size. Large atoms ( & gt ; 10 µm ) are about wholly deposited in the olfactory organ. Researchs on wood dust believe that comparatively that few atoms larger than 5 µm, which form most of the wood dust, yesteryear into the lungs every bit far as the clearance mechanism of the olfactory organ is non impaired. The inquiries on whether wood dust or dust from one or several forests contains carcinogens have been raised. There is no clear reply to this inquiry. A really big figure of chemical constituent are present in wood. Cellulose, polyoses, lignin, terpene, terpenoids, fats, waxes and phenolic compounds such as tannic acids, but none is a known carcinogen. ( Leclerc and Luce. , 1998 ) Types of business are straight related to the sum of exposure to wood dust. Lumbermans and sawmill workers are exposed to comparatively big atoms of fresh wood. The average degree of wood dust is by and large lower than 1mg/m3. Wooden furniture industry and cabinet devising involves a big figure of woodworking procedures, such as sawing, planning, come offing, sanding and usage of milling machines that produce wood dust ( Nylander et al. , 1993 ) A assortment of species are used, with predomination of hardwood for high quality furniture manufactured by cabinet shapers, for illustration in Asiatic states. The average size of the atoms may be particularly little, because the forests need to be really dry, which produces really finer atoms and the sanding, is much finer for furniture industries, for aesthetic grounds. There is some grounds that sanding of hardwood can bring forth finer smaller atoms. ( Acheson. , 1976 )2.3 Sanding of wood.Sandpapering is smoothing the surface of wood â €Å"an scratchy procedure in which borders of little, difficult, crystalline atoms are quickly drawn across the surface of the wood, with force per unit area being applied perpendicular to the surface† ( Holliday et al. , 1986 ) . The smaller the scratchy atoms, the finer the dust produced, and the faster the smoother, the greater the sum of dust produced. Sandpapering is the normally used come uping method continuing wood coating ( Williams and Morris. , 1998 ) . The chief aim of sanding is to do surfaces free of seeable defects every bit good as to makes surfaces uniformly absorbent for coatings ( Richter et al. , 1995 ) Sandpapering is done in many wood industries, with little, handheld smoothers to big membranophones or belts for smoothing a full panel. There are few different ways in sanding of wood. The most common are the belt smoother, where a uninterrupted strip of emery paper rotated between two rollers, the disc smoother, where a round piece of emery paper fastened to a revolving disc, the membranophone smoother, where a uninterrupted strap of emery paper rotated on a membranophone, and the orbital smoother, which operates with an egg-shaped, vibrating gesture. Use of manus held electric smoothers has been identified as a peculiarly dust-covered procedure, which would take to exposure to dust. Wood dust concentrations vary with type of dust extraction, sum of wood removed, and type of smoother ( Thorpe and Brown et al. , 1995 ) . For electrical orbital smoothers without built-in dust extraction, entire inhalable or inspirable dust concentrations ranged from 0.42 to 8.01 mg/m3, dust concentrations were reduced 84.3 % to 97.97 % when the smoothers were used with fitted bags. For electric belt smoothers, entire inhalable dust concentrations ranged from 10.2 to 19.8 mg/m3 without built-in dust extraction and were reduced 66.1 % to 93.5 % with bags. For electric orbital smoothers with external dust extraction, entire dust concentrations ranged from 0.022 to 0.739 mg/m3, and respirable dust concentrations ranged from 0.003 to 0.936 mg/m3. Rotary smoothers with external dust extraction produced entire dust concentrations ranged from 0.002 to 0.699 mg/m3, and respirable dust ranged from 0.001 to 0.088 mg/m3. A survey carried out on the dust coevals features of hardwoods during sanding procedure reveals that sum of wood removed during the sanding procedure predetermined dust-generation, although the wood denseness and scratchy grit used played a function. Consequently, low denseness wood species produced higher dust-concentration due o its comparative easiness of sanding, and vice-versa. Different sanding operations will bring forth different sum of dust concentration ( Graham and Ratnasingam.,2007 ) . This is proven by a survey carried on six hardwood species stand foring commercially of import hardwoods use in Malayan wood merchandises fabricating industry selected based on hardness and denseness as in Table 2.1.Hardwood speciesAverage denseness ( kg/m3 )Average hardness ( N )Resak ( Vatica sp. )8707040Balau ( Shorea sp. )8206980Kelat ( Syzygium sp. )6705140Merawan ( Hopea sp. )6405080Rubberwood ( Hevea sp. )5403440Meranti ( Shorea sp. )5303610Table 2.1: Malayan Hardwood species used in wood merchandises fabricating industry. ( Taken from Dust-generation features of hardwoods during sanding procedures ) Ratnasingam et al. , 2009. From the survey conducted, it is shown that the sum of wood removed is the most of import factor finding dust-generation during wood sanding processes. Machine sanding utilizing belt-sanding procedure yielded the highest dust concentrations compared to manus sanding. This is shown by the important alteration in dust concentration shown in Table 2.2 below. .ProcedureDust concentrations ( mg/m3 )Average wood remotion ( gms )Hand sanding197Orbital sanding269Wide belt-sanding4318Edge sanding166.5Stroke sanding3111Brush sanding115.5Table 2.2: Dust concentration at different sanding procedures: Taken from dust-generation features of hardwoods during sanding procedures. by Ratnasingam et al. , 2009. Based on the consequences, about all sanding operations produced dust concentration higher than the standard allowable dust exposure degree of 5mg/m3, proposing that sanding dust control is of import in the furniture fabrication industry, if wellness and safety criterions are traveling to be met ( Graham and Ratnasingam et al. , 2007 ) .2.4 Properties and Toxicity of wood dustWood dust is one of the most common organic dusts workers are exposed to in the furniture fabrication industry. ( Ratnasingam et al. , 2009 ) . Surveies have found that exposure to wood dust can do wellness effects like rhinal mucosa harm, annoyance and Sino-nasal malignant neoplastic disease, while deep lung deposition can take to lung malignant neoplastic disease and impaired respiratory map ( Shamssain. , 1992 ) and ( Mikkelsen. , 2002 ) . Therefore a survey was undertaken to measure air-borne wood dust concentration and its atom size distribution in the Malayan Rubberwood furniture industry, one of the large st wood industry in South East Asia. Sampling periods of 8 hours were undertaken at the routing and hand-sanding work Stationss to find the Time-weighted mean value of wood dust concentration. The mean air-borne dust concentration recorded for routing work station ( 63mg/m3 ) was lower than the sanding work station ( 89 mg/m3 ) . This value was higher than the standard eight hr Time Weighted Average Maximum Exposure Limit for wood dust of 5mg/m3 ( FMR1989, HSE1999 ) , and hence the high air-borne wood dust concentration in the mills poses respiratory-related wellness hazards.In footings of atom size distribution, this survey revealed that less than 25 % of the air-borne dust by weight at the two work Stationss were less than 10 µm. Hence, the emanation during consequences indicate that merely a little part of the air-borne wood dust atom is capable of perforating into the lower parts of respiratory system to do serious wellness jobs. However, this survey besides show that it is due to air-borne wood dust concentration, and non the wood dust atom size distribution that posses serious menaces to the respiratory system of workers in the Rubberwood furniture fabricating mill s. Another survey did carried out was to measure air borne dust emanation ( 0.1-10 µm ) during the routing operation of Rubberwood ( Hevea Brasiliensis ) in the furniture industry in South East Asia. ( Ratnasingam et al. , 2009 ) . The emanation of airborne wood dust during the machining of Rubberwood ( Hevea Brasiliensis ) consequences in increased incidence of respiratory jobs and rhinal malignant neoplastic disease among workers in the South East Asiatic furniture industry ( Anon. , 2008 ) .Rubberwood ( Hevea Brasiliensis ) being the most of import natural stuff for the wooden furniture industry in the South East Asia part, therefore the survey on the consequence of dust emanation during its machining are of import as to set up a benchmark for industrial wellness guideline for the Rubberwood processing industry in this part. The consequences showed airborne dust in the scope of 0.1-10 µm had the most terrible consequence on the wellness of workers. 68 % of the workers confirmed as agony from some respiratory-related jobs after five old ages of drawn-out exposure. The experiments showed that the mean bit thickness has the greatest influence on dust coevals during the routing operation followed by wood wet content and rake angle. It is shown that airborne dust emanation during the routing procedure of Rubberwood could be minimized by aiming an mean bit thickness of 0.1mm, while maintaining the wet content in 12-14 % scope. These should remain as guidelines to minimise the airborne dust emanation, which in bend will cut down the wellness jeopardy posed by airborne dust to workers in Rubberwood furniture mills in South East Asia ( Ratnasingam et al. , 2009 ) .2.5 Human malignant neoplastic disease surveies of wood dustRecent surveies of wood dustIn December 2000, a study by U.S Department of Health and Hum an Services National Toxicity Program entitled â€Å"Report on Carcinogen for Wood Dust† stated in its drumhead statement that Wood dust is known to be a human carcinogen, based on sufficient grounds of carcinogenicity from surveies in worlds. It has been demonstrated through human epidemiologic surveies that exposure to wood dust increases the happening of malignant neoplastic disease of the olfactory organ ( rhinal pits and paranasal fistulas ) . Strong and consistent associations with malignant neoplastic disease of the rhinal pits and paranasal pits were observed both for businesss associated with wood dust exposure and for straight estimated wood dust exposure. Hazards were highest for glandular cancer, and other types of nasal malignant neoplastic diseases ( squamous cell carcinoma of the rhinal pit ) and malignant neoplastic diseases at other sites, including the nasopharynx, the voice box, and Hodgin ‘s disease have been associated with wood dust exposure in several epidemiologic surveies. The function of specific chemical constituents of the wood ( of course happening or exogenously added compounds ) in wood dust-induced carcinogenesis is ill-defined. The particulate nature of wood dust may besides lend to wood dust-associated carcinogenesis since dust generated by wood working typically consists of a high proportion of atoms that are deposited in the nasal cavity.Chronic exposure to wood dust particulates is associated with reduced mucociliary clearance and enhanced inflammatory reactions in the rhinal pit in some surveies in worlds. Additionally, cellular alterations ( metaplasia and dysplasia ) observed in the rhinal mucous membrane of wood workers and laboratory animate beings may stand for preneoplastic provinces. A survey on 4247 adult females employed in a Norse mush and paper factory for at least one twelvemonth between 1920 and 1993, supervising their malignant neoplastic disease incidence from 1953 to 1993, supervising their malignant neoplastic disease incidence from 1952 to 1993. Compared with the national female population, adult females employed for at least three old ages in mush and paper work showed an ovarian malignant neoplastic disease standardized incidence ratio ( SIR ) of 1.6 ( 95 % CI = 1.1 to 2.3, 3.1 instances ) . Elevated SIRs were seen for lung malignant neoplastic disease and multiple myeloma in adult females with less than three old ages exposure, but non for longer exposures. No rhinal malignant neoplastic disease instances occured in the population. Wood dust exposure was non estimated straight, doing dose response hard to measure, and the survey ‘s size limited its power for most results ( Langseth and Anderson et al. , 1999 ) ( Imos et al. , 2000 ) studied 3723 male and 3063 female workers employed at two furniture mills in Estonia from 1946 onward, followed through 1995 for incidence of malignant neoplastic disease. Workers were classified as holding low, medium, , or high strength of exposure based on employment records. Nasal consonant malignant neoplastic diseases were twice every bit common as expected, compared with the national population, but this was based on merely three instances ( all of which occured among extremely open workers. ) The lone significantly elevated hazard rose with strength of exposure among adult females, but non among work forces ; incorporation of a 20-year latency premise stengthened the association. The usage of totl incidence alternatively of mortality, every bit good as consideration of strength of exposure and slowdown effects, were strenghts of this survey. However, the sample size limited the ability to observe elevated hazards of rarer malignant neoplastic diseases. In a survey conducted on genotoxicity of wood dust in a human embryologic lung cell line, utilizing cell civilization technique, a survey on comparative genotoxic activities of two difficult forests ( beech and oak ) and a soft wood ( pine ) a cell civilization with human lung cells. It is learn that among the untreated forests processed in furniture industries, difficult forests, peculiarly beech and oak have been often suspected to incorporate carcinogenic belongingss in their natural components. It has been shown that beech wood infusions induce weak mutants in bacteriums ( McGregor 1982 ; Mothashamipur et al. , 1986 ) , an enhanced figure of atomic abbreations in duodenal crypts of mice ( Mothashamipur and Norpoth. , 1989 ) , micronuclei in rhinal epithelial tissue of rats ( Nelson et al. , 1993 ) , and malignant tumours on mouse tegument ( Mothashamipur et al. , 1989 ) . Although occupational exposure to wood dust is encountered during all phases of wood processing, the comparatively higher hazard of developing malignant neoplastic disease is associated with the increased degree of wood dust in the ambiance ( Mothashamipur et al. , 1989b ) . However, the strongest associations of exposure to wood dust and malignant neoplastic disease development is observed in businesss where merely difficult forests but no additives are used ( Nylander and Dement. , 1993 ) . The consequences of the survey show that extracts of untreated difficult forests cost important chromosomal and chromatid interruptions in embryologic lung cells, but such a phenomenon was non observed with the deal. A farther comparative survey on DNA-strand interrupting effects of hardwoods ( beech, oak ) and a deal ( spruce ) has been done in vitro utilizing rat hepatocytes ( Schmezer et al. , 1994 ) .2.6 Surveies of malignant neoplastic disease in Experimental animate beingsCarcinogenicity o f wood dust and wood additives in rates exposed by long term inspiration.In 1965, Macbeth reported on 20 patients with rhinal glandular cancers in the country of High Wycombe in England, of whom 15 had worked in the furniture industries. Between 1967 and 1972, more elaborate information was provided and in 1969, the tumours were recognized as occupational disease. Numerous epidemiological and toxicological surveies of the carcinogenic consequence of wood dusts were published, which fundamentally confirmed the consequences obtained in England. In 1985, oak and beech wood dusts were classified as carcinogenic to worlds by Senate committee of the German Society for the promotion of Scientific Research ( Deutsche Forschungsgemeinschaft ) in Germany, and other wood dusts as suspected carcinogens. In 1999, hardwood dusts were classified as carcinogenic agents by the Commission of the European Union, on the footing of the IARC categorization of the carcinogenic potency of wood dusts in 199 5. A research undertaking was initiated to measure exposures happening in the wood industry consistently, and to understand better the manner of formation of glandular cancer of the olfactory organ. Epidemiologic surveies were excluded, as the figure of noxious agents was excessively great, and neither employers nor workers know precisely what type of agents were used, although the type and additives such as varnish, discolorations, gums and wood preservatives that are used are known, frequently the pretreatment of the wood is unknown Long-run experiments in which animate beings were exposed to inspiration seemed to be a suited method, provided that the malignant neoplastic diseases observed in worlds could be induced in research lab animate beings under comparable conditions. As the Numberss of agents was excessively big for systematic proving in such experiments, short-run surveies of toxicity and genotoxicity were carried out to function as a footing for the design of long term exper iments. Material used in the survey include Oakwood dust, because it is the most genotoxic of the wood tested ; the genotoxicity was tested with cyclohexane infusions. Wood preservatives incorporating lindane and pentachlorophenol ( PCP ) , because lindane was genotoxic in human nasal cells. Chromate is besides used, which is genotoxic, includes drawn-out rhinal clearance and, when used in wood preservatives, may take to dysplasia. Chromate has often been used in the wood-processing industry, peculiarly as K bichromate in discolorations but besides as a repair agent in wood preservatives A group exposed to N-nitrosodimethylamine ( NDMA ) served as positive controls, because rats exposed to certain nitrosamines are known to develop tumours of the rhinal pit. Exposure and animate being handling were performed harmonizing to the German Law on the Protection of Animals. The exposure tracts of rats to wood dusts and wood preservatives are such that all the coops of all seven experimental groups were rotated daily within their exposure boxes, harmonizing to a strategy documented for each group and twenty-four hours. When all exposed animate beings are considered together, the consequences go even more pronounced. Fatal respiratory piece of land tumours occurred in the five of 155 animate beings exposed to oak wood ( P = 0.08, Fischer trial, when compared with the negative control ) , in five of 102 animate beings exposed to chromate ( P = 0.03 ) and in two of 101 animate beings exposed to lindane and PCP ( P = 0.17 ) while such tumours were non seen in the 96 negative cont rols. These measurings in the terminal do non allow a decision about the extent to which chromate histories for the effects associated with exposure to oak and beech wood dust or for the epidemiologically ascertained regional fluctuations in tumorigenesis. More wood types from different parts will hold to be analyzed for chromate and compared.2.7 Minimizing dust emanation by the usage of tool geometry.Dust created in the machining of wood is a major job in the on the job environment. Minute wood atoms carried through the air make a serious wellness jeopardy, in utmost instances even taking to malignant neoplastic disease. In wood working industries, it has proved a jeopardy to workers wellness, particularly in the signifier of malignant neoplastic disease of the nasal and paranasal fistulas. A sum-up of probes of wood dust and the hazard of malignant neoplastic disease can be found in Nylander and Dement ( 1993 ) , where the writers states that secret agents in the wood working industry face a higher hazard of developing rhinal malignant neoplastic disease, particularly those working with machines that generate wood dust. An experimental survey did by J. Palmqvist et al. , 1999 on the influence of cutting informations and tool geometry in cut downing dust emanations at the beginning, that is at the tip of the tool. Method used on three different wood stuffs such as, pine, beech and fiberboard ( MDF ) . Specimens were processed in a miling machines where it was possible to change the film editing informations. The dust emanations from the tool ( defined here as atoms with a diameter less than 10 µm ) were measured. The parametric quantities altered in the experiments were moisture content of the wood, mean bit thickness, way of provender ( up or down ) and rake angle of the tool. The experiments showed that the mean bit thickness had the greatest influence on the sum of dust created when machining wood and wet content of the wood, a reasonably great influence, and while the way of the provender and and the profligate angle had small or no influence. The consequences show that dust emanations increase quickly when making a certain mean bit thickness. It is hence of import to cipher and command the mean bit thickness in order to minimise the dust emanation between the three wood tested.2.8 Routers and Sanders safety jeopardiesRouters are used for such intents such as cutting and determining cosmetic pieces, doing frame and panel doors, and miling moldings.. The tool-spindle axis is normally perpendicular, but it may be tilted. The operator lowers the caput for machining, and the caput automatically returns to its original place after the cut is made. Operators may be injured from accidental contact with the routing tool when managing stock or taking bit from the tabular array. Kickback is another common beginning of hurt among routers operators. Projections of tools can badly wound or kill router operators. Tools can be flung from the cutter caput if they are ill fastened in the tool holder, if the incorrect tool is used, or if th e tool velocity is excessively high ( A usher for protecting workers from woodworking jeopardies, 1999 ) Router with Adjustable Tool Guard should be used to protect the routers from serious hurt that is caused by crisp instrument in knife vesica. Other that it, equip routers with a spindle braking system that bit by bit engages. In the average clip, some tips on safe work patterns such as properly attach and secure toolsto the holder, and label cutting tool and holders with the maximal allowable spindle velocity. Drum sanders are people who finish stock by utilizing a coated scratchy surface to take stuff. A belt smoother uses a systems of blocks to travel scratchy stuff accross the stock. Either the wood is fed manually or automatically into the machine or the sanding belt is pressed toward the wood, which is located on a working tabular array ( A usher for protecting workers from woodworking jeopardies, 1999 ) . Drum sanders produce quite a considerable measure of all right wood dust. All smoothers should be carefully ventilated. The primary safety jeopardies of belt smoothers us that workers may catch their custodies, vesture or jewellery in the running axial rotations. Safety work patterns should be to replace lacerate, frayed, or exessively worn belts or membranophones. A raddled belt, disc or membranophone can do a monolithic heat buildup, which can do the belt, disc or membranophone to rupture or interrupt and bombard the environing country with its projected spots. It is besides of import to maintain custodies off from scratchy surfaces and sand on the downward-moving side of the disc or belt. . ( A usher for protecting workers from woodworking jeopardies, 1999 ) .Chapter 3: Methodology3.0 Entire dust aggregation utilizing MiniVol Portable Air Sampler.The MiniVol Air Sampler is an ambient air sampling station for particulate affair and non-reactive gas. The patented low flow engineerin g used in MiniVol was developed jointly by the U.S Environmental Protection Agency ( EPA ) and the Lane Regional Air Pollution Authority in an attempt to turn to the demand for portable air pollution trying engineering. MiniVol gives consequences near about as in mention air quality informations. Both precise and accurate, the battery operated, lightweight MiniVol is ideal for trying at distant countries or station web. The MiniVol can be configured to try for a similar mention station web. In the particulate affair ( PM ) trying manner, air is drawn through a atom size centrifuge and so through a filter medium. Particle size separation is achieved by impaction. Actual volumetric flow must be 5 litres per minute ( 5 L/m ) at ambient conditions. Impactors are available with a 10-micron cut -point ( PM10 ) and a 2.5-micron cut-point ( PM2.5 ) . Operating the sampling station without an impactor allows for aggregation of entire suspended affair ( TSP ) . 2 unit of Minivol is used in this undertaking. Both theoretical account is taken to site and operated at 5 litres per minute. First theoretical account of Minivol is situated sanding country where there were two sanding maestro machine and random orbital sanding procedure is taking topographic point. Second theoretical account of Minivol is situated at country of where routing of wood is taking topographic point. This research was carried out in three hebdomads in the month of November and December 2009. Total suspended atom ( TSP ) was collected in this two station. The location to put the Minivol unit was chosen based on the work processes which produce more dust. First station, in routing procedures, dust produced by the routing machines are coarser and more dust are collected by the pump. In the 2nd station, wood sanding procedure by machines and manus is the work processes that were assessed. Sandpapering utilizing machines are done to smoothen the portion of furniture which is non even or to do the furniture finer in quality which make it a better market value.EquipmentSampler:47-mm PVC, 2-5 µm pore size membrane or tantamount membrane filter and back uping tablet in 47mm cassette filter holder.Minivol Air sampling stationMicrobalance, capable of weighing to 0.001mg.Forceps ( sooner nylon )Preparation of filters.Equilibrate the filters in an environmentally controlled weighing country or chamber for at least 2 hours.Number the backup pads with a ballpen pen and topographic point them, numbered side down, in filter cassette bottom subdivisions.Weight the filters in an environmentally controlled country or chamber. The filter tare weight are record, W1 ( milligram ) .Zero the balance before weighing.Manage the filters with forceps.Assemble the filter in the filter cassettes and close firmly so that the escape around the filter will non happen.SamplingCalibrate each Minivol unit with a representative sampling station in line.Sample at 5 L/min for a entire sample of 10 L. Do non transcend a entire filter burden of about 2 milligrams entire dust.Sample readyingWipe dust from the external surface of the filter cassette with a damp paper towel to minimise taint. Discard the paper towel.Remove the top and bottom stoppers from the filter gently to avoid loss of dust.Calibration and Quality ControlZero the microbalance for weighing. Use the same microbalance for weighing filters before and after sample aggregation.MeasurementWeigh each filter. Record the station sampling weight, W2 ( milligram ) , in the air volume sampled. Record anything singular about the filter paper ( e.g. , overload, escape, wet torn, etc. )Calculations:Calculate the concentration of Entire dust particulate, C ( mg/m3 ) , in the air volume sampled, V ( L ) :C = ( W2-W1 ) ( milligram ) Volt: ( F1 + F2 ) x T V ( L )Time Leaden Average, TWA:Net dust weight ( milligram )=milligramFlow rate ( L/min ) x 0.001 ( m3/L ) ten clip ( min )M33.1 Respirable dust aggregation utilizing Personal Air Sampling Pump ( PASP )Respirable dust is the fraction of the entire dust that enters the gas exchange part of the lungs. 2 unit of personal sampling pump used on two specific workers that have lasting work displacement. The trying pump is worn on the neckband of the workers shirt, and is fastened by a limiter. Sampling pump that was used in this research is from the theoretical account Apex HB 3294-04. It uses an efficient stop pump whose flow rate is exactly maintained utilizing an automatic flow control circuit. The pump draws contaminated air through a sampling caput at a rate determined by the caput design or trying scheme. The Apex was developed to supply trying capablenesss between 5 ml/min and 5 l/min, suited for a broad scope of applications including solvent exhausts, asbestos clearance and personal sampling of dusts. Apex pumps are ideally suited to many of the Total and Respirable dust trying techniques detailed in U.K Health and Safety Executive publication MDHS14, and in other mention methods. The trying pump is operated at 2.2 L/min for Higgins-Dewell cyclone, for 8 hr daily for three hebdomads, from 8am to 5pm, working clip in the mill. The workers are chosen based on the wood processes that they do. The mill does non give its workers revolving occupation mundane, therefore it is easier to try on one individual for the whole twenty-four hours making the same work for an norm of 8 hours. Respirable dust is more of the sum of dust that enters the gas exchange part of the lung, therefore it is a really of import index of how the lung system can be affected by utilizing this instrument.EquipmentSampling station:Filter: 5.0  µm pore size, polyvinyl chloride filter or tantamount hydrophobic membrane filter supported by a cassette filter holderCyclone: 10-mm nylon, Higgins-Dewell ( BGI Inc. , 58 Guinan St. Waltham, MA 02153 ) ( 7 ) or tantamount.Personal Sampling pump, 2.2 L/min + 5 % for HD cyclone with flexible linking tube.Balance, analytical with sensitiveness of 0.001mg.Forceps ( sooner nylon )Environmental chamber or room for balance.Preparation of filters.Equilibrate the filters in an environmentally controlled weighing country or chamber for at least 2 hours.Number the backup pads with a ballpen pen and topographic point them, numbered side down, in filter cassette bottom subdivisions.Weight the filters in an environmentally controlled country or chamber. The fil ter tare weight are record, W1 ( milligram ) .Zero the balance before weighing.Manage the filters with forceps.Assemble the filter in the filter cassettes and close firmly so that the escape around the filter will non happen.Remove the cyclone ‘s grit cap before usage and inspect the cyclone inside. If the interior is visibly scored, fling this cyclone since the dust separation features of the cyclone may be altered. Clean the inside of the cyclone to forestall entrainment of big atoms.Assemble the sampling station caput. Check alliance of filter holder and cyclone in the trying caput to forestall escape.SamplingCalibrate each personal sampling pump to the appropriate flow rate with a representative sampling station in line.Sample 45 min to 8 hr. Make non transcend 5 mg dust lading on the filter.Sample readyingRemove the top and bottom stoppers from the filter cassette. Equilibrate 2 hr in an environment controlled country or chamber.Calibration and Quality ControlWeigh each f ilter. Record this post-sampling weight, W2 ( milligram ) .Calculations:Calculate the concentration of Entire dust particulate, C ( mg/m3 ) , in the air volume sampled, V ( L ) : C = ( W2-W1 ) ( milligram ) Volt: ( F1 + F2 ) x T V ( L )Time Leaden Average, TWA:Net dust weight ( milligram )=milligramFlow rate ( L/min ) x 0.001 ( m3/L ) ten clip ( min )M33.2 Data Analysis.The consequences is analysed utilizing Independent samples T-test on both Total dust value and Respirable dust value. The consequences informations collected for Entire dust and respirable dust in station 1 and station 2 concentration is besides analyzed utilizing Mann-Kendall Trend analysis. Mann-Kendall tendency analysis is a non-parametric trial for indentifying tendency in clip series informations. The trial compares the comparative magnitudes of sample informations instead than the informations values themselves. ( Gilbert. , 1987 ) . One benefit of this trial is that the informations need non conform to any peculiar distribution. Furthermore, informations reported as non-detects can be included by delegating them a common value that is smaller than the smallest mensural value in the information set. The procedurethat will be described i n the subsequent paragraphs assumes that there exists merely one informations valueper clip period. When multiple informations points exist for a individual clip period, the average value is used.3.3 Questionnaire on Occupational exposure to wood dust.The degree of exposure to wood dust is observed through a list of questionnaire to the estimated 30 % of entire workers in the mill. The study was distributed to 30 workers who work for full displacement of 8 working hours for the same everyday work procedures in the mill. Due to linguistic communication barrier among the workers from foreign states such as Bangladesh, Nepal, Vietnam and Indonesia, the questionnaire can merely be used through Bahasa Malaysia as the chief medium. The questionnaire distributed consisted of 3 parts, where first portion covers the personal information ( butir-butir peribadi ) of the workers such as the gender, age, weight, tallness, race and on the job clip. It besides covers on the past business of workers, how long have they work in the current mill and in the yesteryear as good. Separate 2 screens on the past work topographic point status, the environmental scene in which they work, and besides the erosion of Personal Protective Equipment such as mask, safety boots, suited working dress, safety goggles. Part 3 screens their on the job status in their current work topographic point. Same inquiry as proposed to portion 2, but an add-on smoke wont during work clip, and besides current industrial pattern on the cleanliness of dust emanation. A sum of 30 questionnaire were distributed to the workers involved in the mill chosen by choosing workers that are straight involved in this survey, that is routing and sanding procedures. Consequences from respondent are utilizing an analytical tool called Statistical Package for Social Sciences ( SPSS ) version 17.0.3.4 Location of surveyThis survey is carried out in Muar which is The town of Muar is located at 2 °3?N102 °34?E, at the oral cavity of the Muar River. The town is about 150 kilometers ( 93 stat mis ) sou'-east of Malaysia ‘s capitalKuala Lumpur, and about the same distance ( 179 kilometer ) northwest ofSingapore. It is 45km south ofMalacca Town. It is besides 50 kilometers north ofBatu Pahat. Beginning: www.maps.google.com.my Figure 3.1: Location of Muar, Johor. The mill is located at Parit Jamil industrial zone, Muar. There are 100 workers in production line based in the mill, where 60 % are foreign workers coming from Vietnam, Nepal, Bangladesh, Indonesia, Myanmar and local Malaysian. The mill operates from Monday to Saturday except for public vacations and Sunday. There are 5 section including Management squad where all the wood is process by modeling, determining, routing to finally do out a all right quality furniture. Below are some of the figures of wood procedures that are done in the mill.Chapter 4: Consequence AND DISCUSSION4.0 Independent samples T-test on Total dust for sanding and routing.The sum suspended atoms informations collected for routing and sanding procedures in the two Stationss was analyzed utilizing SPSS for independent samples T-test on Total dust for the two independent variables, sanding and routing. The chief intent of running the information utilizing T-test is tests the significance of the difference between t he two sample agencies. Hypothesiss: Nothing: the mean of two group are non significantly different Surrogate: the agencies of the two group are significantly different T-Test Based on Table 4.1, the average value of 1.6645mg/m3 for sanding procedures is higher than 1.5051mg/m3 from routing procedures. This means that on norm, sanding procedure output higher entire dust concentration than routing procedure in 17 workers from both Stationss. Therefore based on the average consequences, the void hypotheses is accepted. Table 4.1: Group statistics for Total Suspended Particles in sanding and routing.StationNitrogenMeanStandard DeviationStandard Error MeanSum Suspended AtomsRouting171.5051.92566.22451Sandpapering171.6645.74017.17952T-Test for Total suspended atoms. Premises: 1: Sanding and routing procedures have about equal discrepancy on the dependent variables. 2: Sanding and routing procedures are independent on one another. Based on Table 4.2: The consequences for Levene ‘s trial for equality of discrepancy is that we accept our first premise that is sanding and routing procedures have about equal discrepancy because the value of significance is 0.557 which is greater than 0.05. Therefore the two discrepancy value is non significantly different. Table 4.2: Levene ‘s Test for equality of discrepancies for Total Suspended Particles.Levene ‘s Test for Equality of DiscrepanciesFSig.Sum Suspended AtomsEqual discrepancies assumed.353.557Equal discrepancies non assumedFrom the Table 4.3, Independent samples of t-test shown in equal discrepancies assumed from Levene ‘s trial, it can be conclude from the t value of -0.555 with grade of freedom 32, at important degree of 0.05, there is no important difference between the sanding and routing procedures. The sum of Entire dust produced in the sanding procedure is non significantly different from entire dust from routing procedure. Entire dust is collected from the dust that has accumulated in the ambient air, so it can non be measured specifically from which beginning the dust is coming from. Wind way, comparative humidness and different work undertaking done in same station may impact the motion of this all right dust atoms traveling approximately in the air. Table 4.3: Independent samples t-test for Total Suspended Particlest-test for Equality of MeansTdfSig. ( 2-tailed )Average DifferenceSum Suspended AtomsEqual discrepancies assumed-.55532.583-.15941Equal discrepancies non assumed-.55530.523.583-.159414.1 Independent Samples T-test on Respirable dust for sanding and routing.Based on table 4.4, the average value of 4.4865 for sanding procedures is higher than 2.7509 from routing procedures. This mean on norm, repirable dust on workers is higher in the sanding processes than routing procedures. Table 4.4: Group statistics for respirable dust on sanding and routing procedure.PersonNitrogenMeanStandard DeviationStandard Error MeanRespirableSandpapering174.48651.83743.44564Routing172.7509.81998.19887Based on table 4.5, for respirable dust, the two groups that is sanding and routing has about equal discrepancy for the two dependent variables. And the consequence shows that the important value is greater than 0.05 which is 0.260 which means that they are non significantly different. Table 4.5: Levene ‘s Test for equality of discrepancies for Respirable dustLevene ‘s Test for Equality of DiscrepanciesFSig.RespirableEqual discrepancies assumed1.316.260Equal discrepancies non assumedIn table 4.6, through Levene ‘s trial that the discrepancies are about equal, t value of 3.557 with 32 grade of freedom, at 0.05 important degree, it shows that there is important different in the sum of repirable dust from routing and sanding procedure. Respirable dust is the sum of dust measured in the take a breathing zone of the workers, which means it can mensurate the sum of dust that is inhaled into the lung by take a breathing the air indoors. This is an of import indicant to demo how much different wood working procedure produces different consequence on workers. Table 4.6: Independent samples t-test for Respirable dustt-test for Equality of MeansTdfSig. ( 2-tailed )Average DifferenceStd. Error DifferenceRespirable dustEqual discrepancies assumed3.55732.0011.73559.48800Equal discrepancies non assumed3.55722.130.0021.73559.488004.2 Mann-Kendall Trend analysis of entire dust.Wood dust informations collected during 3 hebdomads of monitoring is divided into two Stationss of wood procedure, that is wood sanding and routing procedure. The entire dust collected for 3 hebdomads is tested to see the correlativity between the clip puting and variables for sanding and routing procedure. Based on table 4.7, the Mann-Kendall tau correlativity coefficient is 0.603. This positive value show an increasing tendency to Total dust value for sanding station. Table 4.7: Mann Kendall analysis for correlativity trial entire dust station1.Kendall ‘s tau Correlation TestUS Geological Survey, 2005Datas set: Example Totaldust values – Mann-Kendall trial, input type 4The tau correlativity coefficient is 0.603S = 82.omega = 3.337P = 0.0008The relation may be described by the equation:Y = 0.43264 + 0.1206 * TenTo back up this consequence, based on figure 4.1, it can be seen that there is a important addition for the 2nd hebdomad ( 14th Dec to 19th Dec 09 ) during this clip period, the concentration of entire dust rise from 1.995 mg/m3 to 2.175mg/m3 ) . For the undermentioned hebdomad, 21st Dec 09 to 26th Dec 09, there is a crisp addition in twenty-four hours 4 of reading, on the 23rd Dec 09, the value recorded was 3.804 mg/m3. This unusual reading may come as a consequence of the air current velocity, weave way and sum of wood being sanded throughout the twenty-four hours. There is a lessening of 2.286 mg/m3 for the last two twenty-four hours of monitoring. The sums of wood dust concentration have decrease due to alter in air current velocity and comparative humidness in the ambiance. High value of comparative humidness can do the air going more concentrated with the dust atoms and when the air current blows, it carries the dust around the ambient air inside the mill. Another factor that contributes to the high emanation of dust in the sanding procedure at station 1 in the 3rd hebdomad of monitoring is due to the usage of machines particularly the usage of two sanding maestro machine which is operated at different velocity and due to the different sum of dust generated by different wood usage, its difficult to command the emanation of dust manually by utilizing vacuity or brushing the floor. This may therefore even do the work topographic point dustier and difficult to maintain it clean. Based on table 4.8: the Mann-Kendall tau correlativity coefficient is 0.691. This positive value shows an increasing tendency for entire dust in station 2. Meanwhile, at 0.05 assurance interval, chance of 0.0001 which means there is important difference in the value of wood dust in station 2 reading every bit good. Table 4.8: Mann Kendall analysis for correlativity trial on Entire dust station 2Kendall ‘s tau Correlation TestUS Geological Survey, 2005Datas set: Example Totaldust values – Mann-Kendall trial, input type 4The tau correlativity coefficient is 0.691S = 94.omega = 3.831P = 0.0001The relation may be described by the equation:Y = 0.74132 + 0.1287 *TenThe graph shown in Figure 4.2 is monitored in station 2. The graph shows a positive increase in hebdomad 1, hebdomad 2 and hebdomad 3 of monitoring. In hebdomad 1, the value of entire dust does non increase significantly but on hebdomad 2, there were steadily increase over the whole hebdomad and this form continue until hebdomad 3 where the highest reading is on the 22nd Dec 09, 2.270 mg/m3. The lowest value was recorded in 18th Nov 09 where the reading is 0.561 mg/m3.The consequence shown in the graph comparing to Figure 1 is non as important in station 1. This is because at station 2, the entire dust concentration in the ambient air is affected by the usage of operating expense piping system where it is used to hoover out all the dust generated by machines and in each compartment, there are besides less dust accumulated throughout the work topographic point.4.3 Mann-Kendall tendency analysis on respirable dust.Table 4.9 shows the consequence end product for respirable dust on electrical orbital sanding procedure. The tau correlativity coefficient is 0.463 and this suggests that there is a positive increasing tendency shown in orbital sanding. Table 4.9: Mann Kendall analysis for Respirable dust on wood sanding procedure.Kendall ‘s tau Correlation TestEssay Writing Service Fully referenced, delivered on clip, Essay Writing Service.Assignment Writing Service Everything we do is focussed on composing the best possible assignment for your exact demandsTaging Service Our Marking Service will assist you pick out the countries of your work that need betterment.View our servicesFree APA Referencing Tool Create your 6th Edition APA mentions rapidly, easy and for free!Free Harvard Referencing Tool Our free online Harvard Referencing Tool makes citing easy.Free Vancouver Referencing Tool Get aid with your Vancouver referencing with our free online tool.Free Study Guides Everything you need to cognize during your surveiesTopographic point an order now Our experts are waiting to assist you with your essayOur experts can assist you with your essay inquiryGet down your orderNo thanksRequest RemovalIf you are the original author of this essay and no longer wish to hold the essay published on the UK Essays web site so delight chink on the nexus below to bespeak remotion:Request the remotion of this essay

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.