The learning process in Vocational High Schools (SMK) Department of Mechanical Engineering is not only done in the classroom. However, it also requires a learning process in the form of a practicum using machine tools or specific materials. However, machines or tools in laboratory room often make a sound that exceeds the threshold value stated in Minister of Manpower Regulation number KEP-51 / MEN / 1999, concerning the noise threshold value in the workplace, which is set at 85 dB and the duration of noise exposure, at most 8 hours.
This situation makes the National Committee for Deaf and Hearing Response interested in researching the effect of noise on hearing loss due to exposure to machine noise that students continuously receive during their activity in laboratories room. The results of this study can be used as consideration for policymakers in the prevention of hearing loss of engineering students majoring in vocational engineering using machines nationally.
This research was conducted by Dr. Indra Zachreini, dr., ENT -KL (K), Prof. Dr. Jenny Bashiruddin, dr., Sp.THT -KL (K), dr. Damayanti Soetjipto, Sp.THT -KL (K), and Dr. Nyilo Purnami, dr., Sp.THT-KL (K), FICS, FISCM. At least 638 students were the subjects studied. They are vocational students from various majors, including; Metal fabrication, wood construction, electrical, automotive, production, software engineering, heavy equipment engineering, welding engineering, machining engineering, motorcycle engineering, light vehicle technical, artificial fiber spinning engineering, and carpentry engineering.
The research team conducted a sound level meter examination and audiometric examination. The sound level meter serves to assess the value of noise exposure from machines in the SMK laboratory. Then, the audiometric examination serves to assess the hearing function of SMK students. The result of the sound level meter found 71.8% or 458 exposure due to machines in the laboratory, which was within the safe threshold. However, 180 laboratory machine exposures fall within an unsafe threshold. This value is immense, and considering its potential to damage the hearing system, prevention is necessary. Results within safe limits also need to take precautions to minimize further cases of hearing loss in vocational students due to exposure to machine noise. According to a study previously conducted by Zachreni I and Putri DB (2015), noise levels on machines that are near the unsafe limit can be caused by the following:
- 1. They are using iron cutting machines, welding machines and others simultaneously. Usually happens because each student is divided into several practice groups using different tools or machines. Thus, it can cause an increase in noise.
- 2. Machines are old, non-standard machines (assembled machines) or machines that lack maintenance.
- 3. The practicum room does not meet the standards, the room is too small, or there is a large machine in one room. The noise level also increases in the practicum room with inadequate ventilation.
- 4. The number of students in the practice room and the noise caused by the practicum machine, they often have to speak loudly so that it can increase the noise in the room.
According to audiometric examination results, it was found that 234 students had hearing problems. This is consistent with our initial assumption that a noisy environment can lead to hearing loss. Besides, it was also found in this study that the level of noise and hearing loss experienced by students of SMK level XII Department of Mechanical Engineering has a significant effect.
Attention and handling related to this problem are undoubtedly needed so that it does not become a big problem in the future. In fact, this can be prevented by using ear protection before entering the laboratory or by adjusting the length of time students can enter the laboratory.
Author: Dr. Nyilo Purnami, dr., Sp.THT-KL (K), FICS, FISCM
Link:
Zachreini, I., Bashiruddin, J., Soetjipto, D., & Purnami, N. (2020). Noise Impact to Hearing Disorder at Vocational School Students Using Machinery in Indonesia. Annals of Biology, 36(2), 276-280.
