| 1. |
- Graff, Pål, 1973-, et al.
(författare)
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Evaluating Measuring Techniques for Occupational Exposure during Additive Manufacturing of Metals : A Pilot Study
- 2017
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Ingår i: Journal of Industrial Ecology. - : John Wiley & Sons. - 1088-1980 .- 1530-9290. ; 21:Suppl. 1, s. S120-S129
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Tidskriftsartikel (refereegranskat)abstract
- Additive manufacturing that creates three-dimensional objects by adding layer uponlayer of material is a new technique that has proven to be an excellent tool for themanufacturing of complex structures for a variety of industrial sectors. Today, knowl-edge regarding particle emissions and potential exposure-related health hazards forthe operators is limited. The current study has focused on particle numbers, masses,sizes, and identities present in the air during additive manufacturing of metals. Mea-surements were performed during manufacturing with metal powder consisting es-sentially of chromium, nickel, and cobalt. Instruments used were Nanotracer (10 to300 nanometers [nm]), Lighthouse (300 nm to 10 micrometers), and traditional filter-basedparticle mass estimation followed by inductively coupled plasma mass spectrometry. Resultsshowed that there is a risk of particle exposure at certain operations and that particle sizestended to be smaller in recycled metal powder compared to new. In summary, nanosizedparticles were present in the additive manufacturing environment and the operators wereexposed specifically while handling the metal powder. For the workers’ safety, improvedpowder handling systems and measurement techniques for nanosized particles will possiblyhave to be developed and then translated into work environment regulations. Until then,relevant protective equipment and regular metal analyses of urine is recommended.
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| 2. |
- Ljunggren, Stefan, et al.
(författare)
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Biomonitoring of Metal Exposure During Additive Manufacturing (3D Printing)
- 2019
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Ingår i: SH@W Safety and Health at Work. - : Elsevier. - 2093-7911 .- 2093-7997. ; 10:4, s. 518-526
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Tidskriftsartikel (refereegranskat)abstract
- Background: Additive manufacturing (AM) is a rapidly expanding new technology involving challenges to occupational health. Here, metal exposure in an AM facility with large-scale metallic component production was investigated during two consecutive years with preventive actions in between.Methods: Gravimetric analyzes measured airborne particle concentrations, and filters were analyzed for metal content. In addition, concentrations of airborne particles <300 nm were investigated. Particles from recycled powder were characterized. Biomonitoring of urine and dermal contamination among AM operators, office personnel, and welders was performed.Results: Total and inhalable dust levels were almost all below occupational exposure limits, but inductively coupled plasma mass spectrometry showed that AM operators had a significant increase in cobalt exposure compared with welders. Airborne particle concentrations (<300 nm) showed transient peaks in the AM facility but were lower than those of the welding facility. Particle characterization of recycled powder showed fragmentation and condensates enriched in volatile metals. Biomonitoring showed a nonsignificant increase in the level of metals in urine in AM operators. Dermal cobalt and a trend for increasing urine metals during Workweek Year 1, but not in Year 2, indicated reduced exposure after preventive actions.Conclusion: Gravimetric analyses showed low total and inhalable dust exposure in AM operators. However, transient emission of smaller particles constitutes exposure risks. Preventive actions implemented by the company reduced the workers' metal exposure despite unchanged emissions of particles, indicating a need for careful design and regulation of the AM environments. It also emphasizes the need for relevant exposure markers and biomonitoring of health risks.
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| 3. |
- Mellin, Pelle, 1985-, et al.
(författare)
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Nano-sized by-products from metal 3D printing, composite manufacturing and fabric production
- 2016
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Ingår i: Journal of Cleaner Production. - Sweden : Elsevier. - 0959-6526 .- 1879-1786. ; 139, s. 1224-1233
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Tidskriftsartikel (refereegranskat)abstract
- Recently, the health and environmental perspective of nano-materials has gained attention. Most previous work focused on Engineered Nanoparticles (ENP). This paper examines some recently introduced production routes in terms of generated nano-sized by-products. A discussion on the hazards of emitting such particles and fibers is included. Fine by-products were found in recycled metal powder after 3D printing by Selective Laser Melting (SLM). The process somehow generated small round metal particles (~1e2 mm) that are possibly carcinogenic and respirable, but not small enough to enter by skin-absorption. With preventive measures like closed handling and masks, any health related effects can be prevented. The composite manufacturing in particular generated ceramic and carbonaceous particles that are very small and respirable but do not appear to be intrinsically toxic. The smallest features in agglomerates were about 30 nm. Small particles and fibers that were not attached in agglomerates were found in a wide range of sizes, from 1 μm and upwards. Preventive measures like closed handling and masks are strongly recommended. In contrast, the more traditional production route of fabric production is investigated. Here, brushing residue and recycled wool from fabric production contained few nano-sized by-products.
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| 4. |
- Thorneus, Erik, et al.
(författare)
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Occupational Exposure to Metalworking Fluid and the Effect on Health Symptoms-An Intervention Study
- 2021
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Ingår i: Journal of Occupational and Environmental Medicine. - : LIPPINCOTT WILLIAMS & WILKINS. - 1076-2752 .- 1536-5948. ; 63:10, s. E667-E672
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Tidskriftsartikel (refereegranskat)abstract
- Exposure to metalworking fluid has been shown to cause health problems among workers. The aim of this study was to compare health outcomes and levels of exposure among workers exposed to metalworking fluid before and after the implementation of preventive measures. The frequencies of self-reported symptoms, as well as the concentrations of measured substances were lower after the implementation of preventive measures. Logistic regression showed statistically significant differences in the report of irritations, a stuffy or runny nose, eye irritation, a hoarse or dry throat, and a cough with odds ratios of 0.31 (95% confidence interval [CI] 0.21 to 0.47), 0.12 (95% CI 0.05 to 0.29), 0.13 (95% CI 0.06 to 0.28), and 0.24 (95% CI 0.12 to 0.46), respectively. This confirms the efficiency of the performed intervention and highlights the importance of eliminating the recirculation of contaminated air.
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| 5. |
- Westling, Katarina, et al.
(författare)
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Bartonella henselae antibodies after cat bite
- 2008
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Ingår i: Emerging Infectious Diseases. - : Centers for Disease Control and Prevention (CDC). - 1080-6040 .- 1080-6059. ; 14:12, s. 1943-1944
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Tidskriftsartikel (refereegranskat)
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