Vibration-induced White Finger Research Articles

Microvascular abnormalities induced by hand-transmitted vibration reflects in finger systolic blood pressure: a cross-sectional study in China.

Local vibration can cause microcirculatory abnormalities such as blood stasis and symmetrical intermittent digital artery vasospasm. Finger SBP (FSBP) measurement is a potential way of assessing vascular components. This study aims to comprehensively investigate the relationship between the occurrence of the vibration-induced white finger (VWF) and changes in FSBP and then set the application value of FSBP measurements in the early diagnosis of VWF. All samples were judgmental sampling from one factory. Totally 50 patients with VWF were the case group, while 50 without occupational hand-transmitted vibration exposure were the control group. FSBP measurements and epidemiological feature investigations were taken. There were significant reductions in FSBP level and %FSBP index at both 10 °C and 30 °C in fingers reported VWF ( P < 0.05). The %FSBP abnormal rate of the index, ring and little finger in the VWF group was higher than the control (44.00% vs. 18.00%, 78.00% vs. 26.00%, 64.00% vs. 8.00%). The %FSBP of the ring and little finger had a relatively high application value (area under curve = 0.902, 0.737), while their standard regression coefficients were -0.23 and -0.412. The diagnostic cutoff value of the ring finger was 77.60%, while the sensitivity and specificity were 86.67%. FSBP measurements were proven helpful in monitoring and diagnosing VWF prospectively and proved to have great application value in our study. %FSBP of the ring finger was the appropriate diagnostic index in FSBP measurements, while its abnormal value could be set as 80.00%.

Exposure-response relation for vibration-induced white finger: effect of different methods for predicting prevalence.

A pooled analysis of vibration-induced white finger (VWF) in population groups of workers has been performed using the results of a published meta-analysis as source material (Nilsson T, Wahlström J, Burström L. Hand-arm vibration and the risk of vascular and neurological diseases a systematic review and meta-analysis. PLoS One. 2017:12(7):e0180795. https://doi.org/10.1371/journal.pone.0180795). The methods of data selection follow those described previously by Scholz et al. (in Scholz MF, Brammer AJ, Marburg S. Exposure-response relation for vibration-induced white finger: inferences from a published meta-analysis of population groups. Int Arch Occup Environ Health. 2023a:96(5):757-770. https://doi.org/10.1007/s00420-023-01965-w) to enable comparison with the results of the present work. The analyzed epidemiologic studies contain different prevalences of VWF observed after different durations of employment involving exposure to the vibration of power tools and machines. These prevalences are transformed to 10% prevalence by either linear or polynomial (i.e. "S"-shaped curvilinear) interpolation in order to compare with the exposure-response relation contained in the relevant international standard (ISO 5349-1:2001). An exposure-response relation is constructed using regression analysis for the time (in years) to reach 10% prevalence in a population group, when subjected to a daily vibration exposure calculated according to the procedures specified in the standard, A(8). Good fits to the data are obtained when polynomial and linear prevalence interpolation is used. The 95-percentile confidence intervals (CIs) of the exposure-response relation predicted by polynomial prevalence interpolation lie at somewhat larger lifetime exposures than those obtained by linear prevalence interpolation. Uncertainty in the precision of polynomial prevalence interpolation is mitigated by giving equal weight to linear interpolation when interpreting the results. When the 95-percentile CIs of the exposure-response models obtained by linear and polynomial prevalence interpolation are used to define the most probable exposure-response relation, the resulting common range of values includes the ISO exposure-response relation. It is proposed that an exposure-response relation for the onset of VWF derived from a regression analysis is specified in terms of the lower limit of its CI. Hence, when exposure measures are constructed according to the ISO standard and equal weight is given to the results of the 2 methods for interpolating prevalence described here, the ISO exposure-response relation would be considered to provide a conservative estimate for a 10% prevalence of VWF to develop in a population group, at least for A(8) > 4 m/s2. It thus remains the relation to use for assessing exposure to hand-transmitted vibration in the workplace. Additional research is needed to resolve inconsistencies in the ISO method for calculating daily exposures.

A Study on Vascular Regulators as Early Biomarkers of Hand Arm Vibration Syndrome.

Purposes of this study are to study the changes in expression of vascular regulators after vibration exposure and during the onset of vibration-induced white finger (VWF) and to screen for vascular regulatory factors that could be used as early biomarkers of HAVS. Using judgmental sampling from a Chinese factory, workers with VWF and hand-transmitted vibration exposure but without VWF were selected for research. Blood samples were taken from all subjects, and the levels of nine of the vascular regulators were measured using ELISA. Receiver operating characteristic curve analysis was performed on nine vascular regulators to assess their diagnostic sensitivity for VWF with the following area under the curve results: PGI 2 = 0.861, ANP = 0.840. Collectively, PGI 2 and ANP exhibited the most potential for the early diagnosis of HAVS.

Exposure–response relation for vibration-induced white finger: inferences from a published meta-analysis of population groups

PurposeIt is questioned whether the exposure–response relation for the onset of vibration-induced white finger (VWF) in ISO 5349-1:2001 needs to be revised based on the epidemiologic studies identified by Nilsson et al. (PLoS One https://doi.org/10.1371/journal.pone.0180795, 2017), and whether the relation they derive improves the prediction of VWF in vibration-exposed populations.MethodsA pooled analysis has been performed using epidemiologic studies that complied with selection rules and reported a VWF prevalence of 10% or more, and exposure constructed according to the provisions of ISO 5349-1:2001. The lifetime exposures at 10% prevalence were calculated for various data sets using linear interpolation. They were then compared to both the model from the standard and that developed by Nilsson et al.ResultsRegression analyses reveal excluding extrapolation to adjust group prevalences to 10% produce models with 95-percentile confidence intervals that include the ISO exposure–response relation but not that in Nilsson et al. (2017). Different curve fits are obtained for studies involving daily exposure to single or multiple power tools and machines. Studies with similar exposure magnitudes and lifetime exposure durations but markedly different prevalences are observed to cluster.ConclusionsA range of exposures and A(8)-values is predicted within which the onset of VWF is most likely to occur. The exposure–response relation in ISO 5349-1:2001, but not that proposed by Nilsson et al., falls within this range and provides a conservative estimate for the development of VWF. In addition, the analyses suggest that the method for evaluating vibration exposure contained in ISO 5349-1:2001 needs revision.

Landsbergis, Johanning, Stillo Respond to Letter to the Editor.

Landsbergis, Johanning, Stillo Respond to Letter to the Editor.

Local vibration induced vascular pathological structural changes and abnormal levels of vascular damage indicators

BackgroundThe vascular component of the hand-arm-vibration syndrome (HAVS) is often characterized by vibration-induced white fingers (VWF). Active substances secreted by the vascular endothelial cells (VEC) maintain a dynamic balance but damage to the blood vessels may occur when the equilibrium is altered, thus forming an important pathological basis for VWF. This study was aimed at investigating vascular damage indicators as a basis for an early detection of disorders caused by vibration, using the rat tail model. Methods and resultsExperiments were conducted using a control group of rats not exposed to vibration while two exposed groups having different exposure durations of 7 and 14 days were randomly formed. Following exposure, the structural changes of tail tissue samples in anesthetized rats were observed. Enzyme-linked immunosorbent assay (ELISA) was used for analyzing four vascular damage indicators myosin regulatory light chain (MLC2), endothelin-1 (ET-1), vinculin (VCL) and 5-hydroxytryptamine (5-HT) in tail blood samples. We found that both vascular smooth muscle and endothelial cells displayed changes in morphology characterized by vacuolization and swelling in the vibration-exposed group. The levels of vascular damage indicators were altered under the vibration. ConclusionThe degree of vascular pathology increased with the longer duration exposure. Furthermore, the levels of MLC2, ET-1 and 5-HT in rat plasma were associated with vascular injury caused by local vibration.

Blood biomarkers for vibration-induced white fingers. A case-comparison study.

Vibration induced white fingers (VWF) is one form of secondary Raynaud's phenomenon (RP). Vibration exposed workers with RP and vibration exposed controls without RP participated. Blood samples were collected before and after cold challenge exposure (COP). The concentration of von Willebrand factor (vonWf), thrombomodulin (TM), serotonin (SER), endothelin-1 (ET1 ), calcitonin gene-related peptide, or thromboxane A2 was calculated. The diagnostic usefulness of the substances for ruling in the diagnosis of Raynaud's was evaluated. The cases showed a significant lower concentration of vonWf before and after COP, a significant increase of ET1 and a decrease of TM after COP. The diagnostic usefulness of vonWf showed a likelihood of defining a true case by 35%. vonWf, TM, SER, or ET1 are suggested biomarkers for VWF. Diagnostic evaluation of vonWf showed a likelihood of defining a true case by 35% in the diagnosis of RP related to vibration.

Analysis and evaluation of vibration characteristics of a new type of electric mini-tiller based on vibration test

Now the internal combustion engine mini-tiller has become the main and indispensable agricultural machinery in vast hilly and mountainous areas of Southwest China. However, its intense vibration may pose a big threat to operators. As a countermeasure to the tiller vibration, a new type of electric mini-tiller powered with a group of lithium battery and a brushless DC motor was developed. The vibration signals at the handle of the tiller were tested under 6 conditions as follows: the tiller was under states of static and working in the field, at slow, medium and rapid speed, respectively. The signals were processed by means of the time domain eigenvalue analysis and the frequency spectrum analysis. The results show that with the electric motor rated speed increased from 95 to 140 r/min under static conditions, the RMS values increased 122.54%, and with the forward speed increased from 0.30 to 0.80 m/s under working conditions, the RMS values increased 201.78%. When the tiller was working, the first order vibration frequencies were 25.99 Hz, 26.99 Hz and 28.99 Hz at slow, medium and rapid speed respectively, all not within 37.50-65.00 Hz, the sensitive range of human hands to the vibration frequency. In addition, according to the results of hand transmitted vibration analysis, it can be found that compared with operating the internal combustion engine mini-tiller under the same working condition, the onset of vibration-induced white finger can be delayed for 3.70 years to 10.20 years by operation of the new electric tiller. Keywords: electric mini-tiller, vibration characteristics, time domain analysis, frequency domain analysis, hand transmitted vibration DOI: 10.25165/j.ijabe.20191205.4737 Citation: Niu P, Chen J, Zhao J D, Luo Z Y. Analysis and evaluation of vibration characteristics of a new type of electric mini-tiller based on vibration test. Int J Agric & Biol Eng, 2019; 12(5): 106–110.

Hand Arm Vibration of Coconut Grater Machine

Vibration are found almost everywhere in rotating machines. Solving or reducing vibration in rotating machinery is difficult engineering task. The impact of exposure to the vibration operating the coconut scraper machine at conventional method will affected the health, exposure to the physical injury and exposure to the Hand-Arm Vibration Syndrome (HAVS). Basically, Vibration-induced White Finger (VWF) is the most condition the user will suffer when operating the vibration tools. The aim of this study was to measure the level of hand-arm vibration when operating using conventional method at coconut scraper machine and to analyse hand-arm vibration level during operating while using proposed adapter. During measurement, spindle speed of coconut scraper machine operating with 1485 RPM. In this study, for the first measurement between conventional method (free hand) and using glove (latex and leather glove) shows leather glove is better compared with others (free hand and latex glove). The reduction of hand-arm vibration in orthogonal direction (X, Y and Z- axis) are X-axis is 33%, Y-axis is 38% and Z-axis is 8%. The second measurement is using the proposed adapter that was designed and fabricated. The percentages reduction of the proposed adapter as compared to conventional method are X-axis is 38.3%, Y-axis is 51.9% and Z-axis is 25.5%.

Cold water immersion test (10°C, 10min) for diagnosing vibration-induced white finger among a group of polishers in a subtropical environment.

This study aimed to investigate whether the finger skin temperature (FST) after cold provocation (10°C, 10min) is as a useful indicator for assisting in the diagnosis of vibration-induced white finger (VWF) in a group of polishers in a subtropical environment. Ninety male vibration-exposed metal polishers (30 patients and 60 controls) from the Guangdong Province in Southern China were recruited. The FSTs at 30, 20, 10, and 0min before cold water immersion (FSTpre-30, FSTpre-20, FSTpre-10, and FSTbaseline) and 0, 5, 10, 15, 20, 25, and 30min after immersion (FST0, FST5, FST10, FST15, FST20, FST25, and FST30) were measured on the index, middle, and ring fingers of both hands. During the first 20-min adaptation period, there was a significant increase in FST in three fingers on both hands in the two groups. In contrast, there were no significant differences between FSTpre-10 and FSTbaseline. Furthermore, FSTpre-30, FSTpre-20, FSTpre-10, and FSTbaseline of the three fingers in both hands did not differ significantly. During recovery, the indicators FST5-0, FST10-0, R5, and R10 for the index finger of the left hand in patients were lower than for the controls. Among the various indicators, the absolute recovery rate, FST5-0, at 5min after immersion was identified as the best diagnosis indicator with a sensitivity of 76.7% and specificity of 70.0% when applied to the index finger of the left hand. The cold water immersion test as applied in a subtropical environment can have a fair discriminating ability for diagnosing VWF.

Clinical effect and mechanism of acupuncture and moxibustion on occupational hand-arm vibration disease: A retrospective study

IntroductionThis is a retrospective study exploring clinical effect of acupuncture and moxibustion on upper limb disorder induced by occupational hand-arm vibration disease (OHAVD), and preliminarily exploring mechanism of the effect. Methods43 patients diagnosed with occupational HAVD were divided into experimental group (n = 21) and control group (n = 22). Before and after 4 weeks treatment, the occurrence of vibration-induced white finger(VWF) was observed, upper limb function was assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, based on which the DASH scores were determined, and the serum concentration of TNFα was detected using ELISA. ResultsPre-treatment DASH score was not significantly different between two groups, but post-treatment score was significantly lower in experimental group than in control group (21.94 ± 5.79vs.35.87 ± 3.80, p < 0.05).Post-treatment the occurrence of VWF in experimental group was significantly lower than that of pre-treatment (χ2 = 5.081, p = 0.024).88.37% of the pretreatment serum TNFα concentration was above reference range 8.1 pg/ml, and it was not significantly different between two groups. However, post-treatment TNFα concentration in experimental group was significantly lower than that in control group (10.51 ± 3.68 pg/ml vs.14.72 ± 8.66 pg/ml, p = 0.045). Further, the difference in DASH score and TNFα concentration before and after treatment was statistically significant between groups (p < 0.05). ConclusionsCombination of acupuncture and moxibustion may be an effective treatment for occupational HAVD, the mechanism is possibly related to reduction of the serum TNFα levels.

Risk assessment of vascular disorders by a supplementary hand-arm vascular weighting of hand-transmitted vibration.

To provide an updated epidemiological validation for a supplementary method for assessing the risk of vascular disorders from hand-transmitted vibration. The occurrence of vibration-induced white finger (VWF) in the vibration-exposed workers of the Italian cohort of the EU VIBRISKS study was related to measures of daily vibration exposure expressed in terms of r.m.s. acceleration magnitude normalised to an 8-h day, frequency weighted according to either the frequency weighting Wh defined in international standard ISO 5349-1:2001 [Ah(8) in ms- 2] or the hand-arm vascular frequency weighting Wp proposed in the ISO technical report (TR) 18570:2017 [Ap(8) in ms- 2]. To estimate a threshold value for vascular hand-arm vibration risk, the Wp-weighted vibration exposure value Ep,d (in ms- 1.5) was calculated according to the ISO/TR document. The difference in the predictions of VWF between the exposure measures calculated with the frequency weightings Wh or Wp was investigated by means of logistic modelling. Measures of daily vibration exposure constructed with the frequency weighting Wp [Ap(8) and Ep,d], which gives more importance to intermediate- and high-frequency vibration, were better predictors of the occurrence of VWF in the vibration-exposed workers than the metric derived from the conventional ISO frequency weighting Wh [Ah(8)]. There was some epidemiological evidence for a threshold value of Ep,d for the onset of VWF in the vibration-exposed workers. Measures of daily vibration exposure evaluated with the vascular weighting Wp performed better for the predictions of VWF than those obtained with the frequency weighting Wh recommended in ISO 5349-1.

Skin temperature responses to hand-arm vibration in cold and thermoneutral ambient temperatures.

Hand-arm vibration (HAV) from hand-held vibrating machines increases the risk of injury in the form of vasoconstriction in the fingers, commonly named as vibration induced white fingers (VWF). Cold temperature may increase that risk. This experimental study examined and compared the effects of the skin temperature of the hands during and after exposure to HAV in thermoneutral and cold conditions. Fourteen subjects were exposed to three conditions: 25°C with HAV, 5°C with HAV or 5°C without HAV. Their skin temperatures were continuously recorded for the thumbs, index fingers, palms, and back of hands. After 20 min of acclimatization, the subjects held, for five min, two handles where the right handle could vibrate at 5 m/s2 and the left was stationary. Finally, they released their grip and stood still for 10 more min. HAV had no additional cooling effect in cold during gripping of the handles. After the subjects released the handles there was only a HAV-induced cooling effect in the left palm with on average 0.5°C colder skin temperature. A single exposure to HAV will not cause an injury such as VWF, but as the present study show: short-term exposure to HAV causes some changes in skin temperature.

Effect of room temperature on tests for diagnosing vibration-induced white finger: finger rewarming times and finger systolic blood pressures

PurposeThis study investigates the effects of room temperature on two standard tests used to assist the diagnosis of vibration-induced white finger (VWF): finger rewarming times and finger systolic blood pressures.MethodsTwelve healthy males and twelve healthy females participated in four sessions to obtain either finger skin temperatures (FSTs) during cooling and rewarming of the hand or finger systolic blood pressures (FSBPs) after local cooling of the fingers to 15 and 10 °C. The measures were obtained with the room temperature at either 20 or 28 °C.ResultsThere were lower baseline finger skin temperatures, longer finger rewarming times, and lower finger systolic blood pressures with the room temperature at 20 than 28 °C. However, percentage reductions in FSBP at 15 and 10 °C relative to 30 °C (i.e. %FSBP) did not differ between the two room temperatures. Females had lower baseline FSTs, longer rewarming times, and lower FSBPs than males, but %FSBPs were similar in males and females.ConclusionsFinger rewarming times after cold provocation are heavily influenced by room temperature and gender. For evaluating peripheral circulatory function using finger rewarming times, the room temperature must be strictly controlled, and a different diagnostic criterion is required for females. The calculation of percentage changes in finger systolic blood pressure at 15 and 10 °C relative to 30 °C reduces effects of both room temperature and gender, and the test may be used in conditions where the ±1 °C tolerance on room temperature required by the current standard cannot be achieved.

Propagation of Acoustic Waves Caused by the Accelerations of Vibrating Hand-Held Tools in Viscoelastic Soft Tissues of Human Hands and a Mechanobiological Picture for the Related Injuries

As is well known, hand-arm vibration syndrome (HAVS), or vibration-induced white finger (VWF), which is a secondary form of Raynaud’s syndrome, is an industrial injury triggered by regular use of vibrating hand-held tools. According to the related biopsy tests, the main vibration-caused lesion is an increase in the thickness of the artery walls of the small arteries and arterioles resulted from enlarged vascular smooth muscle cells (VSMCs) in the wall layer known as tunica media. The present work develops a mechanobiological picture for the cell enlargement. The work deals with acoustic variables in solid materials, i.e., the non-equilibrium components of mechanical variables in the materials in the case where these components are weakly non-equilibrium. The work derives an explicit expression for the infinite-time cell-volume relative enlargement. This enlargement is directly affected by the acoustic pressure in the soft living tissue (SLT). In order to reduce the enlargement, one can reduce either the ratio of the acoustic pressure in the SLT to the cell bulk modulus or the relaxation time induced by the cell osmosis, or both the characteristics. Also, a mechanoprotective role of the above relaxation time in the cell-volume maintenance is noted. The above mechanobiological picture focuses attention on the pressure in an SLT and, thus, modeling of propagation of acoustic waves caused by the acceleration of a vibrating hand-held tool. The present work analyzes the propagation along the thickness of an infinite planar layer of an SLT. The work considers acoustic modeling. As a general viscoelastic acoustic model, the work suggests linear non-stationary partial integro-differential equation (PIDE) for the weakly non-equilibrium component of the average normal stress (ANS) or, briefly, the acoustic ANS. The PIDE is, in the exponential approximation for the normalized stress-relaxation function (NSRF) reduced to the third-order linear non-stationary partial differential equation (PDE), which is of the Zener type. The unique advantage of the PIDE is that it presents a compact model for the acoustic ANS in an SLT, which explicitly includes the NSRF, thereby enabling a consistent description of the lossy-propagation effects inherent in SLTs. The one-spatial-coordinate version of this PDE in the planar SLT layer with the corresponding boundary conditions is considered. The relevance of these settings is motivated by a conclusion of other authors, which is based on the results of the frequency-domain simulation in three spatial coordinates. The boundary-value problem at arbitrary value of the stress-relaxation time (SRT) and arbitrary but sufficiently regular shape of the external acceleration is analytically solved by means of the Fourier method. The obtained solution is the steady-state acoustic ANS and allows calculation of the corresponding steady-state acoustic pressure as well. The derived analytical representations are computationally implemented. Propagation of the pressure waves in the SLT layer at zero and different nonzero values of the SRT, and the single-pulse external acceleration is presented. They complement the zero-SRT and zero-SRT-asymptote results with the results for various values of the SRT. The obtained pressure values are, at all of the space-time points under consideration, meeting the condition for the adequateness of the linear model. In the case where the SRT is zero, the results well agree with the ones obtained by using the simulation software package LS-DYNA. The dependence of the damping of acoustic variables in an SLT on the SRT in the present third-order case significantly generalizes the one in the second-order linear systems. The related resonance effect in the waves of the acoustic pressure propagating in an SLT is also discussed. The effects of the NSRF-originated memory function provided by the present third-order PDE model are necessary for proper simulation of the pressure, which is of special importance in the aforementioned mechanoboiological picture. The results obtained in the work present a viscoelastic acoustic framework for SLTs. These results open a way to quantitatively specific evaluation of technological strategies for reduction of the vibration-caused injuries or, loosely speaking, achieving “zero’’ injury.

Nailfold capillary morphological characteristics of hand-arm vibration syndrome: a cross-sectional study

ObjectiveThe purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS).MethodsIn total, 113 male gold miners were recruited: 35 workers who were...

Vibration characteristics of golf club heads in their handheld grinding process and potential approaches for reducing the vibration exposure

To control vibration-induced white finger among workers performing the fine grinding of golf club heads, the aims of this study are to clarify the major vibration sources in the grinding process, to identify and understand the basic characteristics of the club head vibration, and to propose potential approaches for reducing the vibration exposure. The vibrations on two typical club heads and two belt grinding machines were measured at a workplace. A simulated test station was also constructed and used to help examine some influencing factors of the club head vibration. This study found that the club head vibration was the combination of the vibration transmitted from the grinding machines and that generated in the grinding process. As a result, any factor that affects the machine vibration, the grinding vibration, and/or the dynamic response of the club head can influence the vibration exposure of the fingers or hands holding the club head in the grinding process. The significant influencing factors identified in the study include testing subject, grinding machine, machine operation speed, drive wheel condition, club head model, mechanical constraints imposed on the club head during the grinding, and machine foot pad. These findings suggest that the vibration exposure can be controlled by reducing the grinding machine vibration, changing the workpiece dynamic properties, and mitigating the vibration transmission in its pathway. Many potential methods for the control are proposed and discussed. Relevance to industryVibrations on handheld workpieces can be effectively transmitted to the hands, especially the fingers. As a result, a major component of the hand-arm vibration syndrome - vibration-induced white finger - has been observed among some workers performing the grinding and/or polishing tasks of the handheld workpieces such as golf club heads. The results of this study can be used to develop more effective methods and technologies to control the vibration exposure of these workers. This may help effectively control this occupational disease.

Tool-specific performance of vibration-reducing gloves for attenuating fingers-transmitted vibration.

BACKGROUNDFingers-transmitted vibration can cause vibration-induced white finger. The effectiveness of vibration-reducing (VR) gloves for reducing hand transmitted vibration to the fingers has not been sufficiently examined.OBJECTIVEThe objective of this study is to examine tool-specific performance of VR gloves for reducing finger-transmitted vibrations in three orthogonal directions (3D) from powered hand tools.METHODSA transfer function method was used to estimate the tool-specific effectiveness of four typical VR gloves. The transfer functions of the VR glove fingers in three directions were either measured in this study or during a previous study using a 3D laser vibrometer. More than seventy vibration spectra of various tools or machines were used in the estimations.RESULTSWhen assessed based on frequency-weighted acceleration, the gloves provided little vibration reduction. In some cases, the gloves amplified the vibration by more than 10%, especially the neoprene glove. However, the neoprene glove did the best when the assessment was based on unweighted acceleration. The neoprene glove was able to reduce the vibration by 10% or more of the unweighted vibration for 27 out of the 79 tools. If the dominant vibration of a tool handle or workpiece was in the shear direction relative to the fingers, as observed in the operation of needle scalers, hammer chisels, and bucking bars, the gloves did not reduce the vibration but increased it.CONCLUSIONSThis study confirmed that the effectiveness for reducing vibration varied with the gloves and the vibration reduction of each glove depended on tool, vibration direction to the fingers, and finger location. VR gloves, including certified anti-vibration gloves do not provide much vibration reduction when judged based on frequency-weighted acceleration. However, some of the VR gloves can provide more than 10% reduction of the unweighted vibration for some tools or workpieces. Tools and gloves can be matched for better effectiveness for protecting the fingers.

Japan's Recent Tendencies of Accidents in Building Facilities and Workers’ Accidents in the Environment of Extreme Temperature

This is the study on safety and quality improvement technique for construction and maintenance of building facilities. In this paper, the tendency of accidents in building facilities for the past ten years is discussed. Among workers’ accidents in Japan, which occur in the environment of extreme temperature, vibration induced white fingers (VWF) or Raynaud's phenomenon observed during particular works in the cold region and the occurrence condition of fatal accidents by heatstroke in the hot sultry region are summarized. Finally, it is about the prevention measures for heatstroke in Japan.

Work disability after diagnosis of hand-arm vibration syndrome.

Our aim was to study the course of vasospastic and sensorineural symptoms after the clinical diagnosis of hand-arm vibration syndrome (HAVS), and the association of current HAVS symptoms with occupational status, self-evaluation of health, quality of life, and work ability. We gathered all HAVS cases diagnosed at the Finnish Institute of Occupational Health in Helsinki and Tampere during 1990-2008. A questionnaire was sent to all these patients (n = 241). Altogether 149 of them (62 %) returned the questionnaire. Cumulative lifelong vibration exposure was evaluated on the basis of the data in the patient files. On average, 8.5 years after the diagnosis of HAVS, approximately one-third of the patients reported improvement in symptoms of vibration-induced white finger (VWF) and the sensorineural symptoms. Young age and shorter exposure time were associated with improvement in VWF symptoms (p = 0.033 and p < 0.001, respectively). Persistent or deteriorated symptoms of both VWF and sensorineural symptoms were associated with lowered work ability, quality of life (EQ-5D), and general health, also after adjusting for age, smoking, and diseases other than HAVS. The patients' own prediction of work ability in 2 years was more negative if the VWF symptoms or sensorineural symptoms had continued after diagnosis of HAVS (p = 0.065 and p = 0.001, respectively). Our results suggest that in about two-thirds of the patients, the HAVS symptoms may stabilize or deteriorate in the follow-up. Considering the effects on work ability, timely prevention measures should be taken more actively to help patients continue their working careers.