Evaluation of health risk experienced by urban taxi drivers to whole-body vibration and multiple shocks

Abstract

This cross-sectional study was done aiming at determining the exposure of taxi drivers to vibration on 35 safe taxis (19 cars with engine volume of 1.325 L, 9 cars with engine volume of 1.645 L, and 7 cars with engine volume of 1.761 L). Measurements were based on ‘ISO 2631-1’ on seats’ pans, by Castel GA2005 vibrometer. The results through two different evaluative methods indicated moderate exposure levels, corresponding to suggestive Health Guidance Caution Zone (HGCZ) in ‘ISO 2631-1’. Evaluation of exposure to the WBV among taxi drivers, in the taxis with low and high mean acceleration values, using the VDV method is preferred over the R.M.S method. In lower accelerations, in all conditions, the mean of the reckoned values in the VDV method was less than the R.M.S method, and in higher accelerations, where there are more differences, and the CF values were higher (PAIK 1761 cars), again the assessed mean duration in the VDV method is less than R.M.S method. In higher accelerations and with fewer crest factors, this matter didn’t hold, and the allowed time in the R.M.S method became lower.

Keywords

Taxi drivers whole body vibration health risk occupational exposure

Introduction

Whole body vibration (WBV) is a known occupational hazard for many workers such as drivers and machinists of heavy and light equipment, and exposure to it is accompanied by physical and mental consequences.^1–4 All means of transportation are subjected to vibration that may cause discomfort, interference with activities, and injuries if transmitted to the driver or passengers. Some people (e.g., taxi and tractor drivers) are at a more distress and health risk from exposure to vibration due to the nature of their job.¹ The literature shows that exposure to whole-body vibration (WBV) could cause undesirable side effects such as metabolic disorders, and cardiovascular and nervous system problems in sitting operators.² Besides, exposure to vibration causes intervention in activities, affects travel convenience, and creates various health effects. Studies show, that passing through the Pothole at ride speeds of 40 km/h and above at depths of 7.5 cm and above, possible health risk happens in the human body.^3,4 In most transport systems, vibration is transferred to passengers via seats. The human body’s ability to transmit vibrations depends on its biodynamic reactions, particularly where the vibration enters the body (like on a seat) and where the vibration is measured on the body (e.g., on the head).⁶ In addition, vibration transferring usually depends on acceleration, transmissibility, interface force, apparent mass during different vibration settings, body posture, age, gender, frequency content, entrance direction, and seat reactions at the vibration entrance place.^5–7 Vibrations with a lower than 12 Hz frequency influence the entire body, while vibrations with a frequency higher than 12 Hz mainly have local effects.^7,8 Prolonged exposure to whole-body vibration, has a strong correlation with low back pain.^9–12 Undesirable side effects in cardiovascular, respiratory, digestive, reproductive, endocrine, and metabolic systems are some health effects related to WBV.^2,9 Exposure assessment of different drivers of different vehicles including tractor drivers (Singh et al., 2023), motor riders (Parvez et al., 2021), subway drivers (Khavanin et al. and El Sayed et al.), car and taxi drivers (Funakoshi et al. and Chen JC et al.), and various passenger aircraft and pilots (Ciloglu H et al. and Burstorm et al., 2006) have been evaluated.^7,13–19 However, the number of conducted researches in the field of exposure to (WBV) with moderate and low severity in jobs like taxi drivers is still limited in Iran. The same limited number of studies on taxi drivers were done according to the basic method.

Man’s response to (WBV) could be investigated with two main standards of ‘ISO 2631-1’ and BS6841, widely used in scientific articles.^4,20,21 In this study, vibration exposure evaluation was done based on the suggested methods of ISO 2631-1: 1997, 2010; i.e., two methods of root mean squares acceleration and vibration dose value (VDV). Utilizing the second method, which is based on the fourth root of biquadratic acceleration, is preferred in evaluating signals with repetitive shocks and a high range of sensitivity.²² ‘ISO 2631-1’ suggests a guide known as HGCZ (Health Guidance Caution Zone) for evaluating the health effects of whole-body vibrations. According to this guide, in exposures less than HGCZ’s boundary, no health effects have been documented, but exposure within the (HGCZ) is injury-potential, and for more than (HGCZ) Boundaries, there is the risk of health effects probability. In an 8-h-long exposure (8-h exposure), low and high boundaries of (HGCZ) are 0.45 and 0.85 m/s² and related (HGCZ) of (VDV) method are 8.5 and 17 m/s^1.75, respectively.²²

This study was conducted to evaluate the exposure of taxi drivers to (WBV) within normal daily activities in normal urban traffic for evaluating the potentiality of health risks resulting from exposure of the drivers.

Materials and methods

Sample size

WBV assessment was done on 35 taxis and their drivers during three successive weeks in March 2022. The samples were randomly selected from the transport fleet of the municipality and were studied on non-rainy working days. Out of 35 explored taxis, 19 of them were Prides with an engine volume of 1.325 L, 9 of them were Samands with an engine volume of 1.645, and 7 of them were Peugeots with an engine volume of 1.761 L. The mentioned cars were stylized as S1325, IK 1645, and PAIK 1761, respectively, based on the name of their manufacturer company and engine volume. Table 1 and Figure 1 shows properties of investigated cars.

Table 1.

Investigated cars properties.

Car properties		Gearbox	Number of gears	Number of cylinders	Engine power	Length (cm)	Width (cm)	Height (cm)	Maximum speed (km/h)	Acceleration from 0 to 100 (sec)	Weight (kg)
Pride	S1325	Manual	5	4	71	395.2	160.5	145.5	170	15	920
Peugeots	IK 1645	Manual	5	4	100	450.2	190.3	146	185	14.5	1220
Samands	PAIK 1761	Manual	5	4	100	440.8	169.4	141	190	11	1120

Figure 1.

Cars appearance feature.

Measurements approaches

• All measurements were done based on the guidelines of ‘ISO 2631-1’ on the seat pan when the seat belt was fastened and no extra cushion was used with the usual velocity for urban travels (20 to 50 km/h) and when the back rest had a 100-degree angle with seat pan (Figure 2). Furthermore, acceleration measurement was done simultaneously on three axes of X, Y, and Z with weighing filters of W_d, W_d, and W_k with Castel GA2005 vibrometer and analyzer.

• Based on ‘ISO 2631-1’ and ‘ISO 10326-1 guidelines: when we had a dominant axis in the measurements of R.M.S acceleration and (VDV) in three axes, we used the dominant axis. When there was not any dominant axis, we utilized the vector sum of value (VSV) method and multiplied factors of 1.4 in X and Y axes as an evaluation scale for each driver or taxi.

• The selected route was one of the busiest areas in the center of Tehran and was 5.6 km long from Gisha gas station to Vanak square. (Figure 3).

• Daily periods have been reported to be 18 h in different articles.¹⁷ In this study, the exposure amount of drivers after averaging the expressed average periods by the drivers equaled 8 h (420 to 540 min). Thus, 8-h-long exposure was used as a scale for determining daily VDV.

• Allowed daily exposure duration (T_E) in R.M.S and VDV methods was estimated based on ‘ISO 2631-1’ equations (1) and (2). In these equations, EB stands for the high or low exposure boundary of 8-h exposure offered by (HGCZ) in (ISO) and T is said to be the daily allowed period (8 h). $T_{E} = T {(\frac{E B}{W R M S})}^{2}$ (1) $T_{E} = T {(\frac{E B}{V D V})}^{2}$ (2)

Figure 2.

Vibration measurement (position of vibrometer and driver).

Figure 3.

Selected route (Google map).

• Calculations and statistical analysis of the results were done by SPSS (Ver. 22). Related correlations have been suggested by ‘ISO 2631-1’.^22,23 ANOVA test was utilized for determining meaningful statistical relationships between cars and different variables with the use of (SPSS), and for discovering the relationship between R.M.S and (VDV) values, the Spearman test was utilized.

• In all samples, in the measured time, there was the driver and another person on the front seat (with the weight of 78 kg and the height of 176 cm), who was there to do configurations and adjustments of the measuring device.

• Note: In this study, for evaluating the effect of the road factors, the uncertainty existing concerning the exposure to high-speed amounts (taxi speeds during measurements were about 20 to 50 km/h) and software limitations like being held up in traffic, completely direct routes and routes with uneven parts were not included in the evaluations and measurements. Ethical considration: IR.SBMU.PHNS.REC.1401.131.

Results

The participating drivers in this study had a mean weight of 77.4 (50–102) kilograms, an average height of 173 cm (160–187), and an average Body Mass Index (BMI) amount of 26.2 (23.2–29). The car’s type and operation degree based on the recorded amount by car’s odometer, mean weight values, height, driving experience, and the measured period for each group of the drivers and cars have been shown in Table 2.

Table 2.

Whole-body vibration measurement data in taxi drivers.

Drivers with following cars	Tire width mm (N)	Operation (km)*1000	Weight (kg)	Height (cm)	Driving experience (year)	Measurement time (sec)
S1325	165 (16)	302.79 (176–400)	77.47 (60–95)	172.89 (160–187)	13.79 (2–35)	964 (696–1221)
S1325	175 (3)	302.79 (176–400)	77.47 (60–95)	172.89 (160–187)	13.79 (2–35)	964 (696–1221)
IK1645	185 (9)	268 (102–388)	81.89 (64–102)	172.33 (162–180)	12.22 (2–23)	926 (699–1138)
PAIK1761	175 (1)	276.29 (110–387)	71.29 (50–85)	173.43 (165–182)	12.43 (6–23)	976 (711–1171)
PAIK1761	185 (6)	276.29 (110–387)	71.29 (50–85)	173.43 (165–182)	12.43 (6–23)	976 (711–1171)
Total sample	165 (16)	288.54 (102–400)	77.00 (50–102)	173 (160–187)	13.11 (2–35)	957 (696–1221)
	175 (4)
	185 (15)

In 26 measured cases, crest factor (CF) amount, at least in one of the axes was higher than 9 (one of the evaluation-determining scales of ISO) and in all 35 samples, its amount exceeded 6, at least in one of the major axes (the recommended critical amount specified in BS 6841). Hence, the second evaluation method (VDV) was used based on the recommendations of valid standards in determining taxi drivers’ exposure amount. Average (CF) values (without any dimension) in the measured axes and different taxis are shown in Figure 4.

Figure 4.

Average CF values (without dimension) in measurement axes and different taxis.

Average frequency-weighted R.M.S acceleration and (VDV) values in this study, in different axes, were assessed based on ‘ISO 2631-1’ standard, and the mean values in the measured time are classified in Table 3.

Table 3.

Average frequency-weighted R.M.S acceleration and VDV values.

Total sample	IK1645	PAIK1761	S1325	Mean
0.28	0.25	0.34	0.27	(rms)X axis
3.37	2.35	5.16	2.56	(VDVX axis
0.30	0.30	0.31	0.29	(rms) X axis
3.15	2.48	4.38	3.02	(VDV) Y axis
0.47	0.43	0.53	0.47	(rms) Z axis
3.80	2.95	4.80	3.84	(VDV) X axis
0.53	0.52	0.58	0.52	Dominant Axis (rms)
5.10	4.40	6.36	4.96	Dominant Axis (VDV)
0.67	0.63	0.74	0.65	Axes’ total (rms)
5.44	4.56	7.18	5.22	Axes’ total (VDV)
0.62	0.57	0.70	0.60	Total/final rms acceleration
12.57	10.65	16.80	11.92	VDV (8h)

Analysis of the measured data of R.M.S acceleration and car type showed that there is a statistically meaningful difference between R.M.S acceleration values of PAIK 1.761 and other types of cars (p < .05). Similarly, there was found a statistically significant difference between VDV amount of this type of cars and other cars.

The difference between measured mean values with acceleration increase of the cars in relation with z-axis in the measured the VDV values (p < .05). In other (VDV) axes and in all three measured axes, R.M.S mean amount in this study, no definite relationship/correlation was existing.

R.M.S calculations show that, in five cases, the weighted R.M.S acceleration amount was higher than in the upper boundary of HGCZ (0.85 m/s^2). Two out of these five cases were related to the 19 S 1325, 2 of them were related to 7 PAIK cars, and one of them was related to the 9 IK 1645 cars (Figure 5).

Figure 5.

The VDV8h and aw values of the WBV measured on the taxi in all. of 35 samples and relevant HGCZ.

Figure 6 shows the exposure period based on the lower boundary of (HGCZ) in all the cars, allowed exposure time in the (VDV) method.

Figure 6.

Exposure duration based on the HGCZ according to basic and VDV method.

Discussion

Based on the Figure 4, the (CF) amount of PAIK 1761 cars was meaningfully higher than (CF) amount of the two other types of cars. Average (CF) values in x-axis in this group of taxis were meaningfully more than such amount in other axes. However, there was no statistically meaningful difference between average (CF) values in the x, y, and z axes for S1325 and IK 1645 cars.

In addition, in Table 3, the obtained results showthat, in general, R.M.S mean values were the highest on the z-axis with the amount of 0.47 m/s²,and they were the lowest in x-axis with the amount of 0.28 m/s² in all the 35 samples. Moreover, in all three types of cars, the mean values of the z-axis had higher R.M.S acceleration in comparison to the mean values of the x and y axes. R.M.S acceleration values of 29 out of 35 samples were in the z-axis (before the multiplication of 1.4 to x,y axis), in 5 samples the dominant axis was the x-axis, and only in one S1325 car, the severe axis was the y-axis. Furthermore, in evaluating (VDV) index, after applying the coefficients of X and Y-axes, almost similar to the R.M.S method, about 75% (26 samples) had a large z-axis. In 9 cases, in 5 of them, the x-axis was the dominant, and in 4 cases, they-axis was the dominant.

Based on the measurements, Z was the dominant axis, which is Compatible with the previous researche in industrial vehicles, trains, and cars.^{9,16,17,21,24–26}

Urban transport drivers, especially taxi drivers, are among those few jobs that are exposed to moderate levels of (WBV) in all working shifts.¹⁸

Taxi drivers of metropolises are usually exposed to 8-h-long vibrations. Considering approximately high values of crest factors in urban environments due to the existence of uneven surfaces and numerous speed bumps on streets, utilizing (VDV) method is more beneficial and shows more precise exposure values.

Furthermore, in this study, a critical amount of crest factor, which equaled 9, was chosen for determining the priority of the evaluative quantitative method of (WBV). Based on ‘ISO 2631-1’ and ‘ISO 10326-1’, in the case of the existence of a dominant axis, the same axis became the scale of evaluation, otherwise, multi-axis measurements were used.^22,23

Reviewing the results of R.M.S acceleration evaluation indicated that exposure values of 8 taxi drivers were proved to be lower than (HGCZ) limit which is 0.45 $\frac{m}{s^{2}}$ ; 4 out of these samples were related to S 1325 drivers and 4 cases were related to IK 1645 drivers. Exposure values of the rest 22 drivers were - within (HGCZ The position of all 35 samples was offered based on (HGCZ), R.M.S, and (VDV) and the relationship between the results of these two indexes in Figure 5. During this research, a moderate relationship (p = .68) was observed between 8-h R.M.S and (VDV) mean values and different axes.

In the VDV method, the exposure values of 6 drivers were higher than the upper boundary of (HGCZ) where 3 samples were S 1325, 2 samples were from 7 drivers of PAIK cars and a sample was related to IK 1645 cars. The results of this part were somehow similar to the results of RMS method. Besides, according to the VDV method, the exposure of 15 drivers was lower than the HGCZ lower boundary and the exposure of 14 drivers was within the HGCZ defined in ‘ISO 2631’. As the measurement results suggest, average R.M.S acceleration values in z-axis equaled 0.47 m/s².

Table 3 demonstrates the measured mean values in the studied taxis in this research and other similar researches. The results of the present study are reported to be higher than 0.39

\frac{m}{s^{2}}

of the dominant axis introduced in the study by Paddan and Griffin, 2002 (0.37 to 0.52) and 0.44 m/s² reported by Funakoshi et al., 2003 and 0.31 m/s² reported by Chen et al, 2003 (0.17 to 0.55). Observed differences in the Table 4 might be due to different reasons including vehicle type, engine power, road surface quality in different countries, crossing conditions and turns and/or driving culture.

Table 4.

Mean R.M.S acceleration and VDV values (standard deviation) extracted from similar studies on urban transport in comparison to the resulted findings of this study.

Evaluation index	Taxis (present research)	El sayed et al¹⁶	Funakoshi et al¹⁷	Chen JC et al¹⁸	Paddan & Griffin²¹
R.M.S acceleration	0.5562	1.60	0.44	0.31	0.339
R.M.S acceleration	1.42 to 0.31	1.18 to 1.60	0.52 to 0.37	0.55 to 0.17	0.75 to 0.26
VDV	12.57	16.04	—	15.06	7.307
VDV	38.68 to 5.81	15.00 to 16.04	—	31.25 to 7.40	Not clearly defined

Based on the demonstrated results in able 3, average R.M.S values were higher in comparison to the values resulted from some studies on cars in Taipei Malaysia and Funakoshiin Japan, and a study by Paddan and Griffin, and are less than the results of the study by El Sayed et al., in Cairo of Egypt, which was only done on two cars and on passengers’ seats. The mean VDV values of this research were 20 to 30% less than the reported values in the study by Chen et al., 2003 and El Sayed et al, 2012, and were about 80 percentage points more than the mean values reported by Paddan& Griffin.

As Figure 6 indicates, in determining the exposure period based on the lower boundary of (HGCZ) in all the cars, the allowed exposure time in the (VDV) method was less than the values resulting from the R.M.S method. The evaluated exposure time through R.M.S method in all the samples based on the lower boundary of (HGCZ), was 2.5 times more than the results through (VDV) method, and in determining exposure time based on the evaluated periods based on the upper boundary of (HGCZ) by R.M.S and (VDV) methods, in all the cases except taxis from PAIK group, average evaluated periods in different cars in (VDV) method was more than R.M.S method.

In a way that, allowed exposure duration, which is based on HGCZ’s upper boundary, through (VDV) method, was about 80% more than the results gained through the R.M.S method. However, the usual (VDV) method is that in these conditions, PAIK cars had the highest R.M.S, (VDV), and (CF) mean values, and the difference between them and the two other types of cars became meaningful (p < .05). Evaluating exposure time based on the upper boundary of (HGCZ) showed that, the evaluated exposure time equals with 65% of the evaluated exposure time by the RMS method. Anyway, the difference between these two conditions is related to the uncertainty of other relevant researche like studies by Alem, Zhao, and Khavanin et al., in various fields.^15,22,25,27

Considering very high differences between evaluated exposure duration by R.M.S and (VDV) methods, it can be interpreted that, still there is a need to many reviews on the limits of (HGCZ) to improve and recommend general or specific (VDV) boundaries (especially the determined upper boundary).²⁸

If presented lower and upper boundaries for military vehicles by Alem are compared to the results of the present study, the exposure period of all 35 drivers go beyond the evaluated limit, and the allowed exposure periods should be decreased.²⁷

The findings of this study display that, based on the daily exposure time and long exposure period of the drivers, cars with high R.M.S acceleration and (VDV) values (PAIK 1761 cars) should be incrementally discarded from the range of public transportation, and cars with low R.M.S and (VDV) values be utilized. In evaluating the results of tire widths, it became clear that cars with tire width of 175 mm were meaningfully lower than the cars with other tire widths. However, there was a negative meaningful relationship in the study by Jiu-Chiuan Chen et al, 2004 for cars with a tire width of 165 mm, which is the counterpart of the results of this study. The values of CF in the tires with a width of 175 mm were less than the results of tires with smaller widths.²⁹

Conclusion

The results show that evaluation of exposure to the WBV among taxi drivers, in the taxis with low and high mean acceleration values, using the VDV method is preferred over the R.M.S method. In lower accelerations, in all conditions, the mean of the reckoned values in the VDV method was less than the R.M.S method, and in higher accelerations, where there are more differences, and the CF values were higher (PAIK 1761 cars), again the assessed mean duration in the VDV method is less than R.M.S method. In higher accelerations and with fewer crest factors, this matter didn’t hold, and the allowed time in the R.M.S method became lower.

Limitations

Due to the limited sample volumes of this study and the very different features of (WBV) in vehicles with various suspension systems, still, serious attempts are required to confirm, update, and reduce whole-body vibration.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This project was supported by the Shahid Beheshti University of Medical Sciences (Grant No. 43003165).

ORCID iDs

Ali Salehi Sahlabadi

Keykāvus Azrah

Younes Mehrifar

Mohsen Poursadeghiyan

References

Nawayseh

Alchakouch

Hamdan

. Tri-axial transmissibility to the head and spine of seated human subjects exposed to fore-and-aft whole-body vibration. J Biomech 2020; 109: 109927.

Singh

Nawayseh

Samuel

, et al. Real‐time vibration monitoring and analysis of agricultural tractor drivers using an IoT‐based system. J Field Robot 2023; 40: 1723–1738.

Kırbaş

. Investigation of the effects of whole-body vibration exposure on vehicle drivers when travelling over covered manholes embedded in public roadways. Int J Ind Ergon 2022; 88: 103277.

Nawayseh

. Effect of the seating condition on the transmission of vibration through the seat pan and backrest. Int J Ind Ergon 2015; 45: 82–90.

Nawayseh

AlBaiti

. Biodynamic responses to whole-body vibration training: a systematic review. J Appl Biomech 2021; 37(5): 494–507.

Singh

Samuel

Dhabi

, et al. Whole-body vibration: characterization of seat-to-head transmissibility for agricultural tractor drivers during loader operation. Smart Agr Tech 2023; 4: 100164.

Ciloglu

Alziadeh

Mohany

, et al. Assessment of the whole body vibration exposure and the dynamic seat comfort in passenger aircraft. Int J Ind Ergon 2015; 45: 116–123.

Hostens

Ramon

. Descriptive analysis of combine cabin vibrations and their effect on the human body. J Sound Vib 2003; 266(3): 453–464.

Wolfgang

Burgess-Limerick

. Whole-body vibration exposure of haul truck drivers at a surface coal mine. Appl Ergon 2014; 45(6): 1700–1704.

10.

Bernard

. Musculoskeletal disorders and workplace factors: a critical review of epidemiologic evidence for work-related musculoskeletal disorders of the neck, upper extremity, and low back. Washington, DC: NIOSH, 1997.

11.

Bovenzi

Hulshof

. An updated review of epidemiologic studies on the relationship between exposure to whole-body vibration and low back pain. J Sound Vib 1998; 215(4): 595–611.

12.

Singh

Nawayseh

Dhabi

, et al. Digital agriculture: analysis of vibration transmission from seat to back of tractor drivers under multidirectional vibration conditions. Int J Indus Eng. 2023; 30(2): 463–473.

13.

Singh

Nawayseh

Singh

, et al. Internet of agriculture: analyzing and predicting tractor ride comfort through supervised machine learning. Eng Appl Artif Intell 2023; 125: 106720.

14.

Parvez

Khan

Bhardwaj

(eds). Muscular discomfort in occupational motorcycle riding. Recent advances in mechanical engineering: select proceedings of ITME 2019. Berlin: Springer, 2021.

15.

Khavanin

Azrah

Mirzaei

, et al. Evaluating subway drivers’ exposure to whole body vibration based on Basic and VDV methods (with ISO 2631-1 standard). Journal of Health and Safety at Work 2014; 4(2): 15–26.

16.

El Sayed

Habashy

El Adawy

. Evaluation of whole-body-vibration exposure to Cairo subway (Metro) passengers. Int J Comput Appl. 2012; 55(8): 7–15.

17.

Funakoshi

Taoda

Tsujimura

, et al. Measurement of whole-body vibration in taxi drivers. J Occup Health 2004; 46(2): 119–124.

18.

Chen

Chang

Shih

, et al. Predictors of whole-body vibration levels among urban taxi drivers. Ergonomics 2003; 46(11): 1075–1090.

19.

Burström

Lindberg

Lindgren

. Cabin attendants’ exposure to vibration and shocks during landing. J Sound Vib 2006; 298(3): 601–605.

20.

Khanin

Mirzaei

Beheshti

, et al. Evaluation of health risk caused by hole body vibation exposure, using ISO 2631-1 and BS 6844 standards. J Health Safe 2014; 4(3): 23–36.

21.

Paddan

Griffin

. Evaluation of whole-body vibration in vehicles. J Sound Vib 2002; 253(1): 195–213.

22.

International Organization for Standardization (ISO) . Mechanical vibration and shock- evaluation of human exposure to whole–body vibration- part 1: general requirements (standard no. ISO 2631- 1: 1997). Geneva, Switzerland: ISO, 1997.

23.

International Organization for Standardization (ISO) . Mechanical vibration - laboratory method for evaluating vehicle seat vibration - Part 1: basic requirements.(Standard No. ISO 10326-1: 1992). Geneva, Switzerland: ISO; 1992.

24.

Smets

Eger

Grenier

. Whole-body vibration experienced by haulage truck operators in surface mining operations: a comparison of various analysis methods utilized in the prediction of health risks. Appl Ergon 2010; 41(6): 763–770.

25.

Zhao

Schindler

. Evaluation of whole-body vibration exposure experienced by operators of a compact wheel loader according to ISO 2631-1: 1997 and ISO 2631-5: 2004. Int J Ind Ergon 2014; 44(6): 840–850.

26.

Azrah

mirzaei

poursadeghiyan

baneshi

ebrahimi

, et al. Evaluation of whole-body vibration exposure among urban metro drivers: comparing ISO2631-1 and ISO2631-5 standards to evaluate exposure. health scope. 2018; 7(2): e55928.

27.

Alem

. Application of the new ISO 2631-5 to health hazard assessment of repeated shocks in US army vehicles. Ind Health 2005; 43(3): 403–412.

28.

Blood

Ploger

Yost

, et al. Whole body vibration exposures in metropolitan bus drivers: a comparison of three seats. J Sound Vib 2010; 329(1): 109–120.

29.

Chen

Chang

Shih

, et al. Using “exposure prediction rules” for exposure assessment: an example on whole-body vibration in taxi drivers. Epidemiology 2004; 15(3): 293–299.