1.0 Ensuring Worker Safety during Sustainable Woodworking, Furniture Making and Carpentry
1.1 Introduction
Furniture building, cabinet making and carpentry in construction projects put workers at risk due to inhaling “finely divided” wood dust; in fact, wood dust is “a known human carcinogen” (Yuan et al. 2014; NTP 2014). “Small solid particles . . . below 75 μm (micrometer) in diameter, which settle out under their own weight but which may remain suspended for some time” are hazardous (WHO 1999). The Occupational Safety and Health Agency (OSHA) Permissible Exposure Limit (PEL) based on volume for inhalable wood dust is 5 mg/m3 while the National Institute for Occupational Safety and Health (NIOSH) sets the Recommended Exposure Limit (REL) at one mg/m3 (NTP 2014:414) The problem is serious, approximately 13,000 deaths from lung disease and cancer reported in 2015 were blamed on dust and chemicals inhaled at UK workplaces (UKHSE 2015).
1.1.1 Morphology
Gomez-Yepes and Cremades (2011) measured microscopic dust to learn the aerodynamic equivalent diameter, chemical composition and shapes. A range of morphologies were found; some of the dust particles were spherical while others were cone-shaped or shaped like rectangular prisms whereas the aerodynamic diameters ranged from 2.09 to 72.9 micrometers (Gomez-Yepes and Cremades 2011). The size and type of the particles need to be identified for best elimination of wood dust using LEV and for best protection from wearing dust masks (Hasan et al. 2012; Pocock 2012).
1.2 Management controls: Cost Hierarchy and Cost
Management are judged along a control hierarchy (OSHA n.d.). The hierarchy starts with the most effective at the top of the inverted pyramid; blue is the most effective (remove the hazard) to red, the least effective (PPE) for protection of nasal cavity and lungs (Chalupka 2010).). (See fig. 2) The lowest level of the cost hierarchy is to implement use of masks, safety glasses or other PPEs (OSHA n.d.). After implementing engineering controls the use of PPEs is usually not be necessary (OSHA n.d.).
Figure 2 Control Hierarchy Steps (NIOSH 2015)
Cost Benefit Analysis (CBA) considers the wood dust and the chemicals that are airborne and places a monetary amount on the risk (Oka, 2003). The efficiency of safety mechanisms are embedded into public policy programmes using CBA (Oka, 2003). Oka (2013:413) points out that Cost Effective Analysis (CEA) is a more reliable tool for assessing toxic chemicals risk because “CEA using loss of life-expectancy (LLE) as an index of effectiveness has its own value.” Registration for ISO 14001 is prohibitively expensive for many SMEs even to the point of exceeding a small enterprise’s annual profit margin (Yiridoe and Marett 2004).
1.2 Regulations
Employers are required by law to reduce health hazards by eliminating the hazard or taking practical and adequate precautions (UK HSE 1974; UK HSE 1999; UKHSE 2013). Occupational asthma, rhinitis and allergies; with symptoms of “fever, cough, and worsening breathlessness and weight loss” are health risks and so is cancer caused by toxic woods that are “respiratory sensitizers” (UKSHSE 2013, pg. 1). Risk is high for pulmonary diseases; because the dust passes from the lungs through the body and can cause liver diseases (UK HSE 2012).
Inhalable dust is defined by BS EN 481 1993 as “airborne material which is capable of entering the nose and mouth” (UK HSE 2002, p, 3).Formaldehyde-based resins are airborne during sawing and sanding (HSE 2012). Substance Hazardous to Health (COSHH) Regulations 2002 apply to hazardous chemicals and the danger of “dust and sparks from (an) abrasive wheel” when resins are present (UK HSE 2012, pg. 5).Wood dust exposure causes nasopharngeal cancers and the closure of the nasal cavity (Binazzi et al. 2015; Siew et al. 2015). In factories the design of the building and types of projects; endangerment includes explosions and fires when wood dust ignites from sparking especially from circular saws (Hedlund et al. 2014).
The furniture and fixtures industry covers about 24 percent of total dangerous global dust incidents due to wood dust (Khan and Buiyan 2013). The airborne dust concentrations caused by sawing, coating or assembling products in plywood mills showed a concentration range of 0.1 to 2.2 mg/m3, in particle-board mills (0.4 to 3.4 mg/m3) and in furniture factories (0.1 to 1.5 mg/m3) (IARC 1995:228-229). Using electric circular saws exposes workers to inhalable wood dust and silica (Garcia et al. 2014). The use of hardwood produces airborne dusts that are considered toxic and regulated under the Control of Substances Hazardous to Health Regulations (COSHH) (UK HSE 2002). COSHH Regulations 2000 assigned softwoods and hardwoods Workplace Exposure Limits (WELs) of not more than 5 mg/m3 per eight hour work shift (HSE 2002).
1.4.1 Workplace Examples
Research of two furniture factories showed that wood dust exposure was reduced by a factor of two indicating that managers focused on reduction of “the highest exposures” and found that factory size does not influence dust exposure management (Schlunssen et al. 2001, p. 167). The average of the dust particle diameters in 54 Danish furniture factories were found to be very low; the “mean was equal to 1.17 ±0.62 mg/m3” within the “range of 0.17 to e.44 mg/m3” (Schlunssen et al. 2002: 23). After only four to seven hours breathing was allowed in order to protect the nasal cavity of workers (Schlunssen et al. 2002).
LEV cleans the air by collection and containing dust and also cleans the air by filtering if needed (UK HSE 2011; Pocock 2012). Ducts are encased in hoods and use fans to suck the contaminated air carried away from the worker’s environment with LEV (Hasan et al. 2012). Regular maintenance and monitoring of LEV systems are required to ensure optimum air flow and performance (Hasan et al. 2012). The air extracted is cleaned by filters and discharged back into the work environment (UK HSE 2011). LEV can remove exposure by more than 90 percent with the appropriate “vacuum extraction source.”
One survey learned that managers for big companies because (a) the supply chain vendors do not understand the needs, (2) face-fitted masks are compulsory for “direct employees” but “does not apply to a lot of the work force because they are supplied by agencies” (IOSH 2014:30). Costs were cited as the main factor for decision-making when purchasing any kind of PPE including fit-to-face maps, leading workers to comment that the least expensive not the most effective masks were supplied (IOSH 2014:30). Therefore employers need to determine if the training and oversight of masks for safety is a savings when compared to engineering controls. Inadequate protection with PPEs is not a good solution. Importantly PPE cannot stop sparking fires, which endanger employees and the building.
1.4.5 Engineering Controls vs. PPE
Inthavong, Tian and Tu (2009, pg. 125) found that ventilation design for woodturning with circular saws, a high exposure activity, is best addressed when ventilation originates at the “roof and had an angled outlet provided greatest total particle clearance and a low number of particles in the breathing plan.”
Collecting dust in a central repository is an engineering control system and workers do not need to wear PPE, which can inhibit their work (Khan and Bhuiyan 2013). The disadvantage is the initial cost of a new safety system, but the correct system chosen is cost effective and decreases the injuries and damage caused by fire or explosions (Khan and Bhuiyan 2013). Khan and Bhuiyan (2013) observed that faulty hood and ducting arrangements caused many problems in dust collects that have been installed, but when the design and installation is done properly the systems work very well. Khalaji et al. (2011) recommend a centrally positioned dust collection system in order to save money.
NIOSH (2015) acknowledges that the initial costs of engineering controls are expensive but state that overtime safety and environmental performance are higher. On the other hand PPE strategies are assumed to be less costly, but oversight on correct use is lacking because PPE is rarely checked on construction sites (Kelm et al. 2013).
Grinders fitted with a shroud decreased inhalable dust concentrations and respirable crystalline silica significantly (Healy et al. 2014). The amount of protection with the shrouds was dependent on the size and style of the grinding tip being used (Healy et al. 2014). The researchers concluded that coupled with PPE for the workers, commercial shrouds on the grinders protected workers’ safety well, but PPE alone was not a good safety strategy (Healy et al. 2014).
1.5 Conclusion
Wood dust morphology produces serious health risks; engineering controls reduce health risks and prevent fire and explosions (WHO 1999). Engineering controls are the most effective and affordable results over the long term (COOSH 2016). Management usually chooses PPEs due to the low cost but PPEs are not cost effective Kelm et al. 2013). Wood dust is not eliminated from the environment with the PPE strategy so workers who do not wear PPE or with ill-fitting PPEs are still at risk (Kelm et al. 2013). PPEs do not address the problem of sparking fires. Even in factories with reduced wood dust concentrations and PPE workers can only work half shifts or up to seven hours depending on the dust accumulation in their naval cavities (Schlunssen et al. 2002). Shrouds decrease dust and silica, the hazardous concentrations vary based on grinding tips; PPE only is not able to protect workers (Healy et al. 2014).
Engineering controls are initially costly but over time engineering control interventions are cost effective, other words they pay for themselves (NIOSH 2015). LEV systems collects, contains and filters dust and eliminates the need for PPE (Pocock 2012). PPE inhibits movement and sight whereas engineering control system like a central dust repository (Khan and Bhuiyan 2013).
1.6 References
Binazzi, A., Ferrante, P., Marinaccio, A. (2015) “Occupational Exposure and Sinonasal Cancer: A Systematic Review and Meta-Analysis”, BMC Cancer 15(49). Available at: http://www.biomedcentral.com/1471-2407/15/49
Bornholdt, J., Hansen, J., Steiniche, T., Dictor, M., Antonsen, A., Wolff, Henrik., Schlunssen, V., Holmila, R., Luce, D., Vogel, U., Husgafvel-Pursiainen, K., Wallin, H. (2008) “K-ras Mutations In Sinonasal Cancers In Relation To Wood Dust Exposure”, BMC Cancer 8(53). Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2278146/
COOSH. 2016. Woodworking Machines: Mitre Saws. OSH Answer Fact Sheets. [Online] Available at http://www.ccohs.ca/oshanswers/safety_haz/woodwork/mitre_saw.html []
Chalupka S. 2010. Control banding for risk management of source chemical agents and other occupational hazards. American Association of Occupational Health Nurses, Inc.; 58(9):404. doi:10.3928/08910162-20100826-04.
Dataon, H., Hall, D. and Birch, B. 2012. Validation of a new method for directional dust monitoring. Atmospheric Environment, 50: 1-8. http://dx.doi.org/10.1016/j.atmosenv.2012.01.018
Ducting Express. 2016. Costs for LEV systems. Ducting Express in the UK. [Online] Available at http://www.ducting-express.co.uk/store/index.php?route=product/search&search=LEV&description=true
EUOSHA (European Union Occupational Health and Safety Agency). 2012. Working with substances hazardous to health: A brief guide to COSHH. HSE, UK Government. pp. 1-10. [Online] Available at http://www.hse.gov.uk/pubns/indg136.pdf
EUOSHA (European Union Occupational Health and Safety Agency). 2003. The practical prevention of risks from dangerous substances at work. European Agency for Safety and Health at Work [Online] Available at https://osha.europa.eu/el/tools-and-publications/publications/reports/106 [2 Jan. 2016]
Kelm, A. Lars Laußat, Anica Meins-Becker, Daniel Platz, Mohammad J. Khazaee, Aaron M. Costin, Manfred Helmus, Jochen Teizer, Mobile passive Radio Frequency Identification (RFID) portal for automated and rapid control of Personal Protective Equipment (PPE) on construction sites, Automation in Construction, Volume 36, December 2013, Pages 38-52, ISSN 0926-5805, http://dx.doi.org/10.1016/j.autcon.2013.08.009
Fishwick, D. and Barber, C. 2012. Pneumoconisosis. Review Article. Medicine, 40(6): 310-313. [Online] Available at http://www.sciencedirect.com/science/article/pii/S1357303912000631 [22 Jan2016]
Gioffre. A., Marramao. A. and Ianno. A. (2012) “Airborne Microorganisms, Endotoxin, and Dust Concentration in Wood Factories in Italy”, Annals of Occupational Hygiene 56(2) pp 161–169. [Online] Available at http://annhyg.oxfordjournals.org/content/56/2/161.full
Gomez-Yepes, M.E. and Cremades, L.V. 2011. Characterization of Wood Dust from Furniture by Scanning Electron Microscopy and Energy-dispersive X-ray Analysis. Industrial Health, 49:492-500. www.ncbi.nlm.nih.gov/pubmed/21697619
Hasan, N. H., Said, M. R., Leman, A. M. (2012) “Local Exhaust Ventilation and Application: A Review”, International Journal of Engineering and Technology 12(4) pp 39-43+. [Online] Available at http://www.ijens.org/Vol_12_I_04/127904-7575-IJET-IJENS.pdf
Hasan, N. H., Said, M. R., Leman, A. M., Pagukuman, B. N. D., Othman, J. (2012) “Data Comparison on Fumes Local Exhaust Ventilation: Examination and Testing Compliance to USECHH Regulation 2000”, Scientific Conference on Occupational Safety and Health (SCI-COSH), Selangor. [Online] Available at http://eprints.utem.edu.my/6629/
Healy CB, Coggins MA, Van Tongeren M, MacCalman L, McGowan P. An evaluation of on-tool shrouds for controlling respirable crystalline silica in restoration stone work. Ann Occup Hyg. 2014 Nov;58(9):1155-67. doi: 10.1093/annhyg/meu069
Hedlund, F.H., Astad, J. and Nichols, J. 2014. Inherent hazards, poor reporting and limited learning in the solid biomass energy sector: A case study of a wheel loader igniting wood dust, leading to fatal explosion at wood pellet manufacturer. Biomass and Bioenergy, 66: 450-459. Available at http://dx.doi.org/10.1016/j.biombioe.2014.03.039 [Accessed
IARC. (International Agency for Research on Cancer. 2012. Leather Dust. A Review of Human Carcinogens: Arsenic, Metals, Fibres, and Dusts. Vol. 100C. IARC, Lyon, France. Available at: http://monographs.iarc.fr/ENG/Monographs/vol100C/index.php [Accessed ]
IARC. (International Agency for Research on Cancer). (1995) Evaluation of Carcinogenic Risks To Humans. Wood Dust and Formaldehyde Vol. 62. IARC, Lyon, France. Available at: http://monographs.iarc.fr/ENG/Monographs/vol62/index.php [Accessed 8 Feb. 2016]
IOSH. 2014. Construction Dust: An industry survey. Leicestershire: IOSH pp. 52. [Online] Available at https://www.iosh.co.uk/~/media/Documents/Networks/Group/Construction/MEM1871%20Dust%20survey.pdf
Inthavong, K., Tian, Z. F., Tu, J. Y. (2009) “Effect of ventilation design on removal of particles in woodturning workstations” Building and Environment 44(1) pp 125–136 Available at http://dx.doi.org/10.1016/j.buildenv.2008.02.002
Khalaji, M., Roshanzadeh, B., Mansoori, A. and Tavassoli, S.H. 2011. Continuous dust monitoring and analysis by spark induced breakdown spectroscopy. Optics and Lasers in Engineering, 50:11-=113. [Online] Available at http://adsabs.harvard.edu/abs/2012OptLE..50..110K
NIOSH (National Institute for Occupational Safety and Health). 2015. Hierarcy of Controls. Workplace Safety & Health Topics. NIOSH. http://www.cdc.gov/niosh/topics/hierarchy/
OSHA. Cost Benefit Analysis. Module 5. Occupational Safety and Health Agency, pp. 1-6. https://www.rit.edu/~w-outrea/OSHA/documents/Module5/M5_CostBenefitAnalysis.pdf
Oka, T. 2003. Cost-effectiveness analyses of chemical risk control policies in Japan, Chemosphere, 53, Issue 4, October 2003, Pages 413-419, ISSN 0045-6535, http://dx.doi.org/10.1016/S0045-6535(03)00007-9.
NTP (National Toxicology Program). 2014. Report on Carcinogens, Thirteenth Edition. Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service. http://ntp.niehs.nih.gov/pubhealth/roc/roc13/
Khan. A.I. and Bhuiyan, M.Y. 2013. “Analysis of Design and Purchase Decision of Central Dust Collection System”. Global Journal of Researches in Industrial Engineering, 13(1), p. 7. http://dx.doi.org/10.1016/j.optlaseng.2011.10.009 [20 Jan. 2016]
National Cancer Institute. n.d. General Information about Nasopharyngeal cancer. National Institute of health. [Online] Available at http://www.cancer.gov/types/head-and-neck/patient/nasopharyngeal-treatment-pdq []
Pocock, D. Health and Safety Executive. 2012. On-tool controls to reduce exposure to respirable dusts in the construction industry: A review. UK Health and Safety Laboratory, HSE, UK Government. pp. 1-34. [Online] Available at http://www.hse.gov.uk/research/rrpdf/rr926.pdf [21 Jan. 2015]
Schlunssen, V., Schaumburg, I., Andersen, N. T., Sigsgaard, T., Pedersen, O. F. (2002) “Nasal Patency is related to dust exposure in woodworkers”, Occupational Environment Medicine 59 pp 23-29 http://oem.bmj.com/content/59/1/23.full
Schlunssen, V., Vinzents, P.S., Mikkelsen, A.B., and Schaumburg, I. 2001. “Wood Dust Exposure in the Danish Furniture Industry using Conventional and Passive Monitors”, Annals of Occupational Hygiene, 45(2): 157-164. Available at http://annhyg.oxfordjournals.org/content/45/2/157.full.pdf [3 Jan. 2016]
Siew, S. S., Kauppinen, Timo., Kyyrönen, P., Heikkilä, P., Pukkala, E. (2012) “Occupational exposure to wood dust and formaldehyde and risk of nasal, nasopharyngeal, and lung cancer among Finnish men”, Cancer Management And Research 4 pp 223-232. Avaialble from http://www.ehjournal.net/content/14/1/1 [Accesses 1 Feb. 2016]
UK HSE. (Health and Safety Executive). 2015. Health and Safety Statistics: Annual Report for Great Britain. 2014/15. UK Government. [Online] Available at http://www.hse.gov.uk/statistics/overall/hssh1415.pdf [9 Jan. 2016]
UK HSE. Health and Safety Executive. 2013. HSG53 Respiratory protective equipment at work: A practical guide. [Online] Available at: www.hse.gov.uk/pubns/books/hsg53.htm [Accessed 5]
UK HSE. Health and Safety Executive. 2012. Toxic woods WIS30. www.hse.gov.uk/pubns/wis30.pdf
UK HSE. (Health and Safety Executive). 2011. Clearing the Air a Simple Guide to Buying and Using Local Exhaust Ventilation (LEV). [Online] Available at: www.hse.gov.uk/pubns/indg408.pdf [
UK HSE. 2002. The Control of Substances Hazardous to Health Regulations 2002. No. 2677. Available at http://www.legislation.gov.uk/uksi/2002/2677/contents/made
UK HSE. 1999. The Management of Health and Safety at Work Regulations 1999. No. 3242. Available at http://www.legislation.gov.uk/uksi/1999/3242/contents/made [Accessed 3 Feb. 2016]
UK HSE (Health and Safety Exectutive). 1974. The Health and Safety at Work Etc Act 1974. Chapter 37. Available at http://www.legislation.gov.uk/ukpga/1974/37/contents [Accessed 3 Feb. 2016]
Vallières, E., Pintos, J., Parent, M-E. and Siemiatyck, J. 2015. Occupational exposure to wood dust and risk of lung cancer in two population-based case-control studies in Montreal, Canada. Environmental Health, 14(1): pp. 9. [Online] Available at http://www.ehjournal.net/content/14/1/1 [2 Feb. 2016]
Kolman, D.A. 2015. A guide to protecting technicians from workplace hazards. Vehicle Service PROS. Photo by Safestart. http://r2.vehicleservicepros.com/files/base/VSPC/image/2015/06/16x9/640x360/PPE_Graphic___Factors_that_Influence_PPE_Compliance.5575974428711.jpg
Yiridoe, E.K. and Marett, G. E. 2004. Mitigating the High Cost of ISO 14001 EMS Standard Certification: Lessons from Agribusiness Case Research. International Food and Agribusiness Review 7(2): 37-62.
Yuan, N., Zhang, J., Lu, L. and Sun, P. 2014. Analysis of Inhalable Dust Produced in Manufacturing of Wooden Furniture. BioResources 9 (4): 7257-7266. [Online] Available at http://www.medsci.cn/Sci/show_paper.asp?id=ed269294897
WHO. 1999. Hazard prevention and control in the work environment: airborne dust. World Health Organization (WHO) Prevention and Control Exchange (PACE), Geneva, Switzerland. WHO, Geneva - WHO/SDE/OEH/99.14. [Online] Available at http://www.who.int/occupational_health/publications/en/oehairbornedust.pdf [Accessed 1 Feb. 2016]
Appendix
Table A- 1 Estimated costs of ISO 14001 Registration in Canada (Yiridoe and Marett 2004)
