Hand-arm vibration in motocross:measurement and mitigation actions

Evaluation of human exposure to vibration in the hand-arm system during motorcycle riding activities

BACKGROUND

The majority of Indians prefer to drive by two-wheeler. Hands are the most important interface between the rider and bike while riding a motorbike. The vibration is transferred to the physical structure by the handlebar as it travels. Long-term exposure to the vibrations may have an impact on various bodily structures.

OBJECTIVE

To measure and analyse the human exposure to vibration in the hand-arm system while riding a motorcycle using a vibrometer.

METHODS

The several types of bikes based on their cc's were evaluated in three different road conditions during this investigation (tar road, concrete road, and gravel road). The subjective and quantitative data of each participant were recorded. The RMS A(8) values were supported for every combination of motorcycles and road conditions, and vibration intensity was evaluated using a tri-axial vibrometer.

RESULTS

The exposure limit value for daily vibration exposure is 5 m/s2 according to the UK Control of Vibration at Work Regulations 2005 standards.This study suggests that the bike with the least amount of vibration be used to prevent hand-arm vibration (HAV) syndrome. This study found that bike C had the least vibration across all three types of roads, which will benefit riders by reducing health issues as they ride. Therefore, it is further examined utilising the Taguchi method with various bike C age groups. Bike C with the lowest age had the least vibration when different bike C ages were compared, hence it was recommended for riding.

CONCLUSION

The vibration level of each bike has a huge impact, which was measured using a tri-axial vibrometer. According to the results, bike C has the least vibration across three distinct types of roads and also provides riders with less health issues while riding bikes. As a result, a moped can drive in three different road circumstances with the least amount of vibration, delivering comfort and safety while lowering vibration levels.

Vibration Exposure and Transmissibility on Dentist's Anatomy: A Study of Micro Motors and Air-Turbines

The use of dental hand pieces endanger dentists to vibration exposure as they are subjected to very high amplitude and vibration frequency. This paper has envisaged a comparative analysis of vibration amplitudes and transmissibility during idling and drilling with micro motor (MM) and air-turbine (AT) hand pieces. The study aims to identify the mean difference in vibration amplitudes during idling, explore different grasp forces while drilling with irrigant injection by the dentist, and various vibration transmission of these hand pieces. The study utilized 22 separate frequency resonances on two new and eight used MMs and two new and eight used ATs of different brands by observing the investigator at 16 different dentist clinics. The study adopted a descriptive research design with non–probability sampling techniques for selecting dentists and hand pieces. Statistical methods like Levene Test of Homogeneity, Welch ANOVA, independent t-test, and Games–Howell test were utilized with SPSS version 22 and MS-Excel. The results reveal that vibration amplitudes and vibration transmissibility when measured at position 2 are higher than in another position 1. Vibrations during idling for used MMs are more than AT hand pieces, and the used MM (MUD) and used AT (AUA) hand pieces differ due to their obsolescence and over-usage. Vibration amplitudes increase every time with the tightening of grasping of the hand piece. Vibration amplitudes for each grasping style of MM hand piece differ from all other grasping styles of AT hand pieces. Routine exposure to consistent vibrations has ill physical, mental, and psychological effects on dentists. The used hand pieces more hazardous as compared to newer ones. The study suggests that these hand pieces must be replaced periodically, sufficient to break between two operations, especially after every hand piece usage. Hence, the present research work can be further extended by creating some control groups among dentists and then studying the vibration amplitude exposure of various dental hand pieces and subsequent transmissibility to their body parts.