Analysis of impact noise induced by hitting of titanium head golf driver

Impact noise of prostate biopsy devices

Objective: To analyse the impact noise generated by prostate biopsy devices.Materials and methods: In a laboratory setting, repeated impact noise was recorded at distances of 50 cm and 100 cm using five brands of device on chicken meat, an apple and an empty target. In a clinical setting, the impact noise levels of prostate biopsy devices were recorded in 40 real patient cases using three brands of device.Results: In the laboratory setting, the average SPL (sound pressure level) peak level ranged from 104.3 to 121.3 dB. The highest impact noise levels were measured with the Monopty device, ranging from 114.8 to 122.4 dB. In the clinical setting, there were no statistical differences between repeated SPL values for each specific target. Also, the noise levels were equal when the same device brand was used at 50 cm and 100 cm. The highest SPLs were recorded with the Monopty device, which ranged from 110 to 127 dB. The corresponding values for the Max-Core and Multicore were from 106 to 122.5 dB and from 108 to 116.5 dB, respectively.Conclusions: Biopsy devices generate high peak levels of impact noise. Personnel performing biopsies are advised to consider using hearing protection, even though the impact noise may not induce permanent hearing loss.

Cochlear Damage Caused by the Striking Noise of Titanium Head Golf Driver

Objectives.

To investigate how mouse cochleae are affected by the striking noise of titanium head golf driver.

Methods.

Thirty-two BALB/c mice (20–22 g) with normal hearing were used. The impact acoustic stimulus generated by the striking of titanium golf driver head was centered around 4.5 kHz with 120.5 dB sound pressure level. The recorded impact noise was provided to mice in two ways with the same exposure time of 288 seconds: 1,440 repetitions and an impact duration of 0.2 seconds for 2 hours (repetitive noise) or serially connected impact noise for 288 seconds (continuous noise). Auditory brainstem responses were measured at baseline, day 7, and day 14 after exposure. The mice were then sacrificed for histology.

Results.

Both groups showed statistically significant threshold shifts immediately after noise exposure. Mice in the continuous exposure group, except for those exposed to 32 kHz noise, recovered from threshold shifts 1–2 weeks after noise exposure. However, in the repetitive exposure group, threshold shifts remained for 2 weeks after exposure. The repetitive exposure group had greater hair cell damage than did the continuous exposure group. Structural changes in the stria vascularis were observed in the repetitive exposure group.

Conclusion.

Overexposure to impact noise caused by hitting of titanium head golf driver may be hazardous to the cochlea, and repetitive exposure may induce greater damage than continuous exposure.