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Regularly handling heavy units can present significant risks of developing musculoskeletal problems. This page tells you how to control this risk and why. You also need to be aware of the general information on manual handling. Pay particular attention to the following things: It can also involve twisting, stooping or reaching upwards. Also consider job demands or time pressure. Workers are particularly at risk if they are repetitively handling blocks heavier than 20 kg. Follow the control steps below. In addition, you should also consider the issues below. Control the risk by following the information below. Use pallet trucks, trolleys etc where possible if you need to move blocks around the site. Do not carry them up ladders. Workers laying in this range should typically be able to safely lay blocks under 20kg at a rate of between 20-30 blocks an hour. Reduce the weight of the block or the laying frequency if you are working outside this range. Widen foundation trenches so that you can lay blocks within it rather than stooping below foot level. Relying on two people to handle blocks heavier than 20kg is not usually a suitable solution to the risk. Keep routes free of obstructions to prevent slips and trips. The injuries usually arise from ongoing repetition of the work and posture during the lifting. These factors can create excessive stresses and strains on the body, which can cause damage to muscles and tendons. For ages people have been building shelters and houses using bricks and blocks bound together by mortar. As a result, the trade of bricklayer gradually evolved into what it is today. However, working methods, materials, tools, equipment, and workplaces may vary between workers, construction projects,1 and countries, leading to differences in health and safety risks. In the Netherlands, codes of practice are developed for various professions in the construction industry aimed at reducing health and safety risks. http://eclearusa.com/images/brother-mfc-5840cn-manual.xml

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These codes are based on consensus between health and safety experts, employers, and employee organisations. Recently, such a code of practice was developed for bricklayers.2 The facts presented here are based on that document or other sources as research studies, expert opinions, questionnaires, and interviews conducted with employers and employees. The risk assessments are compared with international standards and scientific literature. The aim of this paper is to give an overview of the tasks, health and safety risks, and control measures to reduce or eliminate hazards of the job and in the workplaces of bricklayers and their assistants. Bricklayers are engaged in building and renovating houses, offices, and industrial complexes using bricks, blocks, and mortar. The bricklayers’ assistant is responsible for the preparation and the transportation of materials and equipment to the actual workplaces. The bricklayer builds the walls by adding mortar and placing the bricks (one handed) or blocks (two handed) in their correct position. In general, one assistant works for two to five bricklayers. Download full-text PDF Spotlight on the construction industry F or ages people have been building shelters and houses using bricks and blocks bound together by mor- tar. However, working methods, materials, tools, equipment, and workplaces may vary between workers, construction projects, 1 and countries, leading to differences in health and safety risks. Recently, such a code of practice was developed for bricklayers. 2 The facts presented here are based on that document or other sources as research studies, expert opi- nions, questionnaires, and interviews conducted with employers and employ- ees. The risk assessments are compared with international standards and scien- tific literature. TASKS OF THE JOB Bricklayers are engaged in building and renovating houses, offices, and indus- trial complexes using bricks, blocks, and mortar. http://sgd42.ru/userfiles/brother-mfc-5840cn-printer-manual.xml

The bricklayers’ assistant is responsible for the preparation and the transportation of materials and equip- ment to the actual workplaces. In general, one assis- tant works for two to five bricklayers. Over the years, bricklaying, transporting materials and equipment, and block laying have developed into three specia- lised professions, but combinations of them frequently occur. Verstraten and colleagues 10 reported an energetic workload index (V. O 2 max is thought to be acceptable. 11 Worldwide, bricklayers and brick- layers’ assistants experience musculo- skeletal symptoms in one or more body regions more often than other construc- tion workers. 12 13 Table 2 shows the 12 month prevalences of musculoskeletal complaints among Dutch bricklayers and bricklayers’ assistants. This dust may contain quartz. The highest dust concentrations will occur when working indoors. Moreover, quartz dust is considered to cause lung cancer in humans. 20 In the Nordic countries an increased standardised incidence ratio of lung cancer (119; 95 CI 112 to 127) was found in bricklayers compared with a reference population of 53 occupa- tional groups. 21 The dust generated when handling insulation materials contains mineral fibres. In general, the applicable threshold limit value for the mineral fibres is not exceeded. Mortar contains cement. Cement is alkaline and regular prolonged skin contact can result in skin complaints. Allergens that are present in the cement can cause allergic contact eczema. The European action limit of 80 dB(A) 24 WORLD AT WORK 89 www.occenvmed.com This difference in exposure level may be due to different tasks performed by bricklayers in the two countries (for example, the use of a grinder or air hammer when cutting joints between bricks). Climate The work is conducted outdoors and partly indoors. Working outdoors involves exposure to cold or heat, wind, and rain. Indoors, exposure to cold and draughts may occur if the rooms are not fully glazed yet. https://www.thebiketube.com/acros-3jh4e-service-manual

This may lead to musculoskeletal complaints 28 and colds. During the summer, and during sunny weather in particular, there is exposure to ultraviolet radiation, which may result in sunburn or eye irritation. Years of exposure may lead to skin cancer later in life. There is the risk of falling from floors or scaffolding, caused by missing railings or floor jambs not being closed up or sealed off, or as a result of slipping off a ladder. There is also the risk of being injured when handling stones or blocks or when using power tools. Inadequate lighting hampers work and increases the chance of accidents. In 2002 a total of 2380 work related accidents affected the 31 500 Dutch bricklayers. An estimated 59 of these occurred at the work site. 32 Most acci- dents involving construction workers were caused by falling, sprains and strains, or hits by falling materials. Of all work related accidents, almost two thirds of those caused (temporal) dis- ability for work. Psychosocial work demands Economic factors like recession, piece- work payment, scheduling, and produc- tion demands may tend to increase the pressure of work on construction work- ers. 33 Time pressure (34), insufficient involvement in work planning (17), and poor day to day management (16) are the main psychosocial demands perceived by Dutch bricklayers, 22 and may therefore, represent a risk for health complaints or increase the chance of injuries. MEASURES TO PROTECT WORKERS Many consensus based recommenda- tions have been reported in the litera- ture to reduce or eliminate health and safety risks. However, the effects of these recommendations often remain unclear and controlled studies on inter- vention measures are scarce, particularly those on combinations of work demands and workload. Moreover, the knowledge about the effects of imple- mentation strategies for the adoption of preventive measures at the workplaces is even scarcer. https://www.hf-u4.com/images/bri-mar-dump-trailer-manual.pdf

Devices can be used to supply bricks and mortar in an elevated position (see fig 2) to reduce bending by the bricklayer. To ensure that the predicted lumbar load during bricklaying remains below com- puted strength values, Ja ?ger and collea- gues 7 advise that the brick supply be stacked higher than 50 cm. Meijer and colleagues 38 found that greater working heights (30 and 50 cm) for picking up the bricks and mortar significantly reduced oxygen uptake up to 20 from the twelfth layer ( ? 75 cm height of bricklaying) compared with a situation in which there was no adaptation in the storage height of bricks and mortar. Table 3 lists all technical measures aimed at reducing the physical work demands of bricklayers. Most Dutch bricklayers are well aware of these measures, but the degree of use varies considerably throughout the Netherlands. Some measures are not widely used, such as an elevation for bricks and mortar tubs (26), the electric wheelbarrow (15), mechanical transportation of mortar (11), and mechanical height adjustable scaffold- ing (4), while mechanical transporta- tion and mechanical positioning of blocks (see fig 3) are reported to occur frequently or always by 58 and 47 respectively. Measures to reduce exposure to toxic substances A combination of three measures— using gloves, good hygiene, and skin care—reduces the risk of skin damage caused by cement. Close fitting clothing prevents the skin being exposed to the material. When carrying out work at eye level or above head level, facial exposure to mortar and glue can be avoided by wearing a cap and a face shield. Exposure to quartz can be reduced in various ways: use of materials contain- ing little or no quartz, limiting the amount of sawing work by having the blocks supplied already cut to size, or using tools with water supply or local exhaust ventilation. When these mea- sures are insufficient the use of respira- tory protection may be necessary. https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/162871d059f9a5---cae-wah-manual.pdf

However, in the case of handheld tools such as drills and saws, the amount of reduction is lim- ited. It is even more difficult to reduce impulse noises caused by handling or hitting bricks. Therefore, the action limit for harmful noise (80 dB(A) for an eight hour working day) may be exceeded and hearing protection should be worn. Figure 1 Mechanical transportation of bricks. Figure 2 Adjusting working height.Moreover, lighting, views and ventilation could be improved. 42 Measures to increase safety To prevent unsafe work situations, a safety plan and prescriptions are thought to be conditional. Table 4 lists the measures, technical and otherwise, for improving safety at the work site. These measures should be part of the safety plan adopted by the bricklaying companies. On a national scale, these measures are best promoted industry- wide, for instance, through labour- management organisations. 29 Schneider and colleagues 33 argued in favour of supplementary legislation in this respect. Labour inspectorate (USA) or covenants (the Netherlands) are exam- ples of supplementary legislation to assure widespread adoption of safer and less risky work practices. Measures to reduce psychosocial work demands Certain trends and developments in the construction industry (for example, improved logistics, multifunctional teams, educational programmes, and certification 43 ) may help to reduce time pressure and to improve the perceived or actual involvement of bricklayers and their assistants in work planning. Amsterdam: Arbouw, 1997. 4 van der Molen HF, Grouwstra R, Kuijer PPFM, et al. Efficacy of adjusting work ing height and mechanising of transportation on physical work demands and local discomfort in construction work. Submitted. 5 van der Molen HF, Grouwstra R, Kuijer PPFM, et al. Effect of working height adjustment on the physical work demands during construction work. In: IEA 2003. Ergonomics in the digital age. cousinsconstructionservices.com/app/webroot/files/computer-organization-and-architecture-8th-edition-solution-manual.pdf

Proceedings of the 15th Tr iennial Congress of the International Ergonomics Association (CD-ROM). Seoul, 2003. 6 van der Molen HF, Grouwstra R, Kuijer PPFM, et al. Effect of mechanisi ng transpo rt of mater ials on the physical task demands during construction work. Seoul, 2003. 7 Ja ? ger M, Luttmann A, Laurig W. Lumbar load during one-handed bricklayi ng. Construction work and low back disorder. Figure 3 Mechanical lifting of blocks. Table 4 Safety measures (consensus based) to prevent accidents Use approved scaffolding, ladders, lifts, and cranes Use above mentioned equipment in accordance with instructions and avoid overloading Secure floor jambs and edges Adopt safe working practices Use the required protective equipment (i.e. head, feet, skin, ear, facial, and respirat ory protection) Avoid situations in which people can trip over rubbish and equipmen t Ensure that the workplace is tidied up Use the prescribed signals when hoisting Ensure that the crane driver has a hoisting certificate and is well trained and highly experienced Ensure that silos are set up on a stable, sound base so that they cannot tip over Ensure that the electrical equipment complies with all requirements and is well maintained Work carefully Ensure that there is good lighting Ensure that work instruction and training is given, especially if equipment is being used 92 WORLD AT WORK www.occenvmed.com De fysiologische belasting en belastbaarheid van metselaars in de bouwnijverheid (The physiological stress and strain of bricklayers in construction industry). Nijmegen: Department of Physiology, University of Nijmegen, Netherlands, 1987. 11 A ? strand PO, Rodahl K. Textbo ok of work physiology: physiological bases of exercise, 3rd edn. Lund: Department of Physical Therapy, Lund University, Sweden, 1992. 13 Goldsheyder D, Nordin M, Weiner SS, et al. Musculoskeletal symptom survey among mason tenders. Part 1: relati onship to low back pain. Part 2: relati onship to neck and shoulder pain. {-Variable.fc_1_url-

Trade specific trends in self-reported musculoskeletal symptoms and job factor perceptions among unionized construction workers. In: Seppa ?l a ? P, Luopaja ? rvi T, Nyga ? rd CH, et al. eds. IEA 1997. From experience to innovation. Proceedings of the 13th Triennial Congress of the Inte rnational Ergonomics Association. Wageningen, Netherlands: University of Wageningen, 2000. 19 Rappaport SM, Goldberg M, Susi P, et al. Excessive exposure to silica in the US construction industry.Occupational lung cancer risk for men in Germany: results from a pooled case-control study. Work- related cancer in the Nordic countries. Amsterdam: Arbouw, 2001. 23 Kanerva L, Jolanki R, Estlande r T, et al. Incidence rates of occupational allergic contact dermatitis caused by metals. Construction noise in Ontario. Prevalence and pattern of occupational exposure to hand transmitted vibration in Great Britain: findings from a na tional survey. The influence of climatic factors on non-specific back and neck-shoulder disease. Why construction is different. In: Ringen K, Englund A, Welch L, et al. eds. Constr uction Safety and Health. Use of a national hospitalisation register to identify industrial sectors carrying high risk of severe injuries: a three-year cohort study of more than 900,000 Danish men. Ergonomics, applying what we know. Bricklaying: a step by step approach to better work. Evaluatie van nieuwe werkmethoden voor de metselploeg: opgehoogd metselen en mechanisch opperen (Evaluation of new working methods for a team of bricklayer s: heightened bricklaying and mechan isation of transport). Hoofddorp: TNO Arbeid, 2001. 37 Vink P, Miedema M, Koningsveld EAP, et al. Physical effects of new devices for bricklaye rs. https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/162871d2a3b86f---cadworx-2014-manual-pdf.pdf

De belasting van de metselaar; de invloed van het verhoogd plaatsen van speciekuip en stenentas en de invloed van het metseltempo op de fysiologische en ervaren belasting van de metselaar (The load on bricklayers; the influence of heightening bricks and mortar and the influence of work pace on physiological and perceived load on the bricklayer). Nijmegen: Department of Physiology, University of Nijmegen, Netherlands, 1988. 39 Wat ers TR, Putz-Anderson V, Garg A, et al. Revised NIOSH equation for the design and evaluation of manual lifting tasks. Weight and frequency effect on spinal loading in a bricklaying task.Amsterdam: Arbouw, 1999. 43 Konin gsveld EAP, Van der Molen HF. History and future of ergonomics in building and construction. WORLD AT WORK 93 www.occenvmed.com A recent review showed that bricklayers have an increased risk of developing MSD, including LBP and pain in the upper and lower extremities (87), with bricklayers experiencing even more MSD than other construction workers (88) (step 1). The risk factors for MSD among bricklayers have been well documented from several workplace studies (step 2), with manual materials handling being the most prominent (87, 88). These studies showed that for bricklaying assistants, manual materials handling needed for transportation of bricks, blocks and mortar is the most physically demanding task... Using this etiological hypothesis, several (consensus-based) preventive interventions have been developed (step 4) (88), in which the most important interventions can be categorized into: (i) adjusting working height of bricks, blocks and mortar, (ii) mechanization of block laying, and (iii) mechanization of the transportation of materials. The efficacy of these interventions has been investigated in field studies that showed mixed results (step 5), ranging from a substantial reduction of trunk flexion and local musculoskeletal discomfort (88) to no effects on physical risk factors among workers using gypsum blocks (90).. www.corwell.co.uk/userfiles/files/computer-organisation-lab-manual.pdf

A research framework for the development and implementation of interventions preventing work-related musculoskeletal disorders Article Sep 2017 SCAND J WORK ENV HEA Allard J van der Beek Jack Tigh Dennerlein Maaike Huysmans Pieter Coenen Objectives: Work-related musculoskeletal disorders (MSD) are highly prevalent and put a large burden on (working) society. Primary prevention of work-related MSD focuses often on physical risk factors (such as manual lifting and awkward postures) but has not been too successful in reducing the MSD burden. A research framework could link research disciplines thereby strengthening the development and implementation of preventive interventions. Our objective was to define and describe such a framework for multi-disciplinary research on work-related MSD prevention. Methods: We described a framework for MSD prevention research, partly based on frameworks from other research fields (ie, sports injury prevention and public health). Results: The framework is composed of a repeated sequence of six steps comprising the assessment of (i) incidence and severity of MSD, (ii) risk factors for MSD, and (iii) underlying mechanisms; and the (iv) development, (v) evaluation, and (vi) implementation of preventive intervention(s). Conclusions: In the present framework for optimal work-related MSD prevention, research disciplines are linked. This framework can thereby help to improve theories and strengthen the development and implementation of prevention strategies for work-related MSD. View Show abstract. There is strong evidence that MSDs and injuries are a major problem for carpenters, plumbers, electricians, and blocklayers (Goldsheyder et al, 2002). Blocklayers, according to Van der Molen et al (2004), report the highest level of absenteeism and ill health retirement due to MSDs when compared with other trades. Anton et al (2005) found blocklayers were three times more at risk of low back disorders compared to non-construction workers, and have the second highest rate for strains and sprains when compared with other occupational groups... Initial EMG and QEC results demonstrate that blocklayers are at risk of contracting MSDs. The body parts that are mostly at risk include the wrists, lower back, shoulder, and neck confirming previous studies findings Van der Molen et al, 2004, Anton et al, 2005and Goldsheyder et al, 2002 Research is ongoing and further EMG and QEC assessments are planned to evaluate lifting and non-lifting tasks and postural assessment at a range of different course heights. Initial assessments were carried out on the ground level, it is proposed to further expand the research by carrying out biomechanical, and physiological analysis on subjects while blocklaying on scaffolding systems for comparison between groundwork and scaffolding work.. An ergonomic study of blocklaying Conference Paper Apr 2007 Rachel Nugent Enda F Fallon Sarah Hegarty Construction workers are a high-risk group for work related musculoskeletal disorders (MSDs) with Blocklayers being among one of the highest risk trades. The increasing prevalence of such disorders is extremely disturbing for affected individuals in terms of pain and suffering, and in the significant financial losses experienced by them, employees, and the economy. This research project involves an ergonomic risk assessment to investigate MSDs in the Irish blocklaying industry. Initial results, using the Quick Exposure Check, demonstrates that blocklayers have a high probability of contracting MSDs of the wrists, back, shoulder, and neck. Higher activity levels were recorded for the dominant and non-dominant erector spinae and trapezius muscles during lifting tasks when compares to non-lifting tasks using Electromyography analysis. One such intervention is the substitution of heavy building materials (e.g. , Concrete Masonry Unit (CMU) block) with lighter weight alternatives, e.g., light-weight CMU block (LWB).. Prevention strategies for musculoskeletal disorders among high-risk occupational groups Article Full-text available May 2010 Rose Alysha Alysha Meyers The objective of the three studies in this dissertation was to improve methods to prevent musculoskeletal disorders among workers in high-risk occupations. The SI combines measures of several biomechanical risk factors into a single value (SI score). Strain Index scores are usually categorized into four ordinal SI “risk categories.” In Strain Index Study I, multivariate survival analysis models were compared to evaluate the predictive validity of the original SI risk category cut-points to a new set of empirically derived cut-point values among 276 manufacturing workers. The results from this prospective study indicated that the empirically derived cut-points were a better predictor of incident hand-arm symptoms than the original cut-points, especially among women. In Strain Index Study II, Aim 1, exposures to forceful exertions, repetition and non-neutral wrist posture estimated with SI methods were compared to analogous exposures estimated with alternate methods. Statistically significant associations between separate methods designed to assess specific risk factors were observed only for those measuring non-neutral wrist posture. In Aim 2, a multivariate survival analysis model examining associations between incident hand-arm symptoms and biomechanical exposures estimated with the SI was compared to a model examining associations between incident hand-arm symptoms and biomechanical exposures estimated with separate estimates of biomechanical risk factors. Results favored the SI risk category metric to characterize biomechanical exposures compared to separate measures of exposure. The third study, light-weight block (LWB) Intervention Study, was a repeated measures laboratory study of 25 bricklayers performed to estimate the effect of block weight (LWB vs.Bricklaying at ankle or chest heights was generally associated with higher exposure to risk factors than bricklaying at knuckle height. Masonry work involves significant physical demands (Hess et al. 2010;Entzel et al. 2007). Van der Molen et al. (2004) found that the most demanding task of masons was one-handed repetitive lifting of bricks and two-handed lifting of blocks. This case study analyzes 141 masonry incidents that occurred over a period of three years in a large masonry company. Incident analysis and interviews with the safety director and production managers identified the masonry tasks with high frequency and severity of incidents, the task factors that contribute to incidents and the events that resulted in incidents and injuries. Furthermore, the study categorizes the incidents according to the injured workers' position such as foreman, masons, laborers, and forklift operators. The findings indicate that three activities—scaffold erection and dismantling, laying block and material handling are responsible for the highest number of incidents and consequences in terms of days away from work and days with modified task. The second finding in this case is that laborers of masonry crews have disproportionately more accidents compared to the masons. The study makes the following contributions to practice: first, it identifies the high-risk activities of masonry operations that require more effective controls to improve workers' safety, and second it distinguishes between the traumatic injuries of laborers and masons, and identifies the population with higher injury risk. The outcomes of such a survey are reported in terms of relative frequency of MSD complaints for the body parts affected and are analyzed through t test, analysis of variance, or logistic regression. The integrated analysis is done for 76 crane operators of a steel plant in India that considers operators, task, and workplace characteristics as predictors of MSD. The relative risk indices for each of the predictor categories compare the risk of prevalence of MSD. The outcomes of CART-based analysis are objective importance scores that quantify the contributions of the predictors toward the occurrence and severity of MSD. A risk priority index is computed to prioritize the predictor variables with categories in terms of their contribution. The study shows that the lower back and neck and shoulder are the most affected and account for 78.75 of the MSD complaints. CART shows that crane height contributes the maximum for MSD occurrences of both lower back and neck and shoulder. However, for MSD severity, while crane height contributes the most for neck and shoulder, cabin feature (static or movable) contributes the maximum for the lower back. Methods For men in selected occupations in the construction sector we calculated smoking-adjusted odds ratios (ORs) and 95 confidence intervals (95 CIs). For bricklayers we estimated the population attributable fraction (PAF) and the attributable community risk (ACR). Conclusions Our findings provide additional evidence of increased lung cancer risk in Italian bricklayers. The association is plausible because they are exposed to several carcinogens, notably crystalline silica. View Show abstract.The penetration and adoption of innovations within the construction industry has been difficult due to a range of issues that. USING A MANUAL TASKS RISK ASSESSMENT TOOL (ManTRA) TO AUDIT THE POTENTIAL BENEFITS OF INNOVATIVE INTERVENTIONS IN THE CONSTRUCTION INDUSTRY Article Full-text available Marek Plawinski Peter Vi Niki Carlan Enzo Garritano The purpose of this research was to evaluate various innovations in the construction industry using a Manual Tasks Risk Assessment Tool (ManTRA) (Burgess-Limerick, 2003). Innovations were identified using multiple sources including a search of the trade publications, on-site observations, union advice, expert opinion by safety consultants, and links with distributors. The ManTRA was used for a quick assessment of the innovative tools, materials, or practices and their effect on MSD-related risk factors. A total of 18 innovations were assessed - with all but one indicating a decrease in risk. Due to the inherent definition of an innovation, however, there were only a limited number of users, resulting in a lack in statistical power. As a result, the ManTRA was primarily used as a source of analysis to help inform the qualitative research. Despite the benefits offered by the MANTRA as a quick- analysis tool, researchers were made aware of its limitations when studying workplace risk factors. View Show abstract Naar een optimale massa voor kalkzandsteenblokken - Productie, taakkenmerken en energetische belasting Article Full-text available Apr 2007 Paul P W Hopmans Arnaud G Houweling Henk F van der Molen David J Robinson Om te bepalen wat gezondheidkundig een verantwoorde massa van kalkzandsteenblokken is, is onderzoek verricht naar het effect van massa’s van 11, 14 en 16 kg op productie, taakkenmerken en energetische belasting bij in totaal vijftien blokkenstellers werkzaam in de praktijk. Systematische observaties leverden informatie op over productie en taakkenmerken. De energetische belasting is gemeten in termen van HRR en zuurstofopname. De blokkenstellers werkten ruim 7 uur per werkdag en 34 van de tijd werd besteed aan blokkenstellen. Daarom kan op basis van deze uitkomstmaten niet worden bepaald welke blokmassa, in de range van 11, 14 of 16 kg, gezondheidkundig de meest verantwoorde massa is. Vervolgonderzoek naar mechanische belasting kan hier mogelijk wel uitsluitsel over geven.