Attending live concerts and events is a thrilling experience that combines the joy of music with the excitement of a crowd. However, amidst the euphoria, it is crucial to protect one’s hearing. Prolonged exposure to high decibel levels can cause irreversible hearing damage or tinnitus. This article explores safe sound levels, what to expect at various venues, and how to protect your ears effectively.
Understanding Decibel Levels and Safe Limits
Noise-Induced Hearing Loss (NIHL) is caused by exposure to loud noises that can damage the hair cells in the cochlea, leading to permanent hearing loss. High-frequency sounds are usually affected first.
Decibels (dB) measure the intensity of sound. The scale is logarithmic, meaning an increase of 10 dB represents a tenfold increase in intensity. Here’s a breakdown of common sound levels and their potential impact:
- Normal conversation: 60-70 dB
- City traffic: 70-85 dB
- Live concerts: 87-120 dB
- Theaters: 70-90 dB
- Workplaces (with machinery): 85-100 dB
The World Health Organization (WHO) and the National Institute for Occupational Safety and Health (NIOSH, a U.S. federal agency) recommend that exposure to sound levels above 85 dB should not exceed eight hours per day. For every 3 dB increase above this level, the safe exposure time halves. At 100 dB, damage can occur after just 15 minutes of exposure. Therefore, it is essential to take precautions, especially in environments like concerts where sound levels can exceed 100 dB. For sounds of short duration, such as explosions or gunshots (impulse noise), NIOSH recommends that exposure should not exceed 140 dB peak sound pressure level.
What to Expect at Concerts, Theaters, and Workplaces
- Concerts and Music Festivals: These events often feature loud music, amplified sound systems, and enthusiastic crowds. Sound levels can easily reach 110-120 dB near the speakers. It’s common to experience temporary hearing loss or ringing in the ears (tinnitus) after attending a loud concert.
- Theaters: While generally quieter than concerts, theaters can still present significant noise exposure, particularly during action scenes or musical numbers. Sound levels typically range from 70 to 90 dB.
- Workplaces: Occupational noise exposure varies widely. For example, construction sites and factories may expose workers to sound levels exceeding 85 dB. Prolonged exposure in such environments can lead to occupational hearing loss if proper protection is not used.
Ear Protection: Essential for Safeguarding Hearing
Using ear protection is one of the most effective ways to prevent hearing damage. There are several types of ear protection available:
- Foam Earplugs: These are inexpensive and easily available. They reduce sound by about 20-30 dB, depending on the brand and fit. They are suitable for concerts and noisy workplaces. Foam earplugs tend to be inexpensive, but may muffle the frequency spectrum.
- Custom Molded Earplugs: These are tailored to the shape of your ears, offering a more comfortable fit and better sound attenuation. They are ideal for frequent concert-goers or musicians.
- Over-the-Ear Muffs: These provide significant noise reduction and are often used in industrial settings. They can be worn over earplugs for added protection.
- Musician & Concert Earplugs: Designed to attenuate sound evenly across frequencies, these earplugs maintain the quality of music while protecting hearing. They are perfect for both performers and audience members.
Decibel Detection Devices and Apps
With advancements in technology, monitoring sound levels has become easier. Decibel detection devices and smartphone apps can measure environmental sound levels, helping you gauge whether you’re in a potentially harmful noise environment. Some popular options include:
- Sound Meter (Android) and Decibel X (iOS/Android): These apps provide real-time sound level readings and logging capabilities.
- Sound Level Meters: Handheld devices that provide accurate decibel readings. They are useful for those who frequently attend loud events or work in noisy environments.
Protecting hearing is essential, especially in environments where sound levels can reach harmful levels. Understanding safe decibel limits and using appropriate ear protection prevents long-term hearing damage.
Hair Cells
Hair cells in the cochlea are specialized sensory cells that play a crucial role in the process of hearing. Located in the inner ear, these cells are responsible for converting sound vibrations into electrical signals that can be interpreted by the brain. There are two main types of hair cells in the cochlea: inner hair cells and outer hair cells. Each type serves a different function in the auditory process.
1. Inner Hair Cells
Location: Inner hair cells are arranged in a single row along the length of the cochlea, which is a spiral-shaped, fluid-filled structure.
Function: They are the primary sensory receptors for hearing. Inner hair cells convert mechanical sound vibrations into electrical signals (nerve impulses). These electrical signals are then transmitted to the brain via the auditory nerve. Inner hair cells are responsible for detecting sound and are essential for the perception of pitch and volume.
Structure: Each inner hair cell has a set of stereocilia (tiny hair-like projections) on its surface. When sound waves cause the basilar membrane (on which the hair cells rest) to move, the stereocilia are deflected, leading to the opening of ion channels. This mechanical movement is converted into an electrical signal by the cell, which then sends the signal to the brain.
2. Outer Hair Cells
Location: Outer hair cells are arranged in three to four rows along the cochlea.
Function: They act as amplifiers and fine-tuners of sound. Unlike inner hair cells, which directly transmit signals to the brain, outer hair cells can change their length in response to sound stimuli. This motility allows them to amplify and sharpen sound vibrations within the cochlea, enhancing the sensitivity and frequency selectivity of the auditory system.
Structure: Like inner hair cells, outer hair cells have stereocilia, but they also possess the unique ability to contract and elongate. This movement helps to amplify the vibrations of the basilar membrane, making it easier for inner hair cells to detect faint sounds.
Mechanism of Action
- Sound Wave Entry: Sound waves enter the ear and travel through the outer and middle ear to the cochlea.
- Basilar Membrane Movement: These sound waves cause the basilar membrane to vibrate, creating a traveling wave along the length of the cochlea.
- Stereocilia Deflection: The movement of the basilar membrane causes the stereocilia on the hair cells to bend.
- Ion Channel Opening: The bending of stereocilia opens ion channels in the hair cell membranes, allowing potassium ions to enter the cells.
- Depolarization and Signal Transmission: The influx of ions causes depolarization of the hair cells, leading to the release of neurotransmitters at the base of the inner hair cells. These neurotransmitters then stimulate the auditory nerve fibers, sending electrical signals to the brain.
Hair cells are highly sensitive and delicate structures. Damage to these cells, whether from loud noise, ototoxic drugs, aging, or other factors, can result in hearing loss, as they do not regenerate in humans. Protecting hair cells from damage is crucial for maintaining hearing function.
Sudden Hearing Loss
Acupuncture and herbal medicine are effective treatments for sudden sensorineural hearing loss (SSHL). Researchers at the China Academy of Chinese Medical Sciences (Wangjing Hospital) found that a combination of acupuncture and herbs can restore hearing capabilities. In a comparative study, acupuncture and herbal therapy proved more effective than a combination of alprostadil and mecobalamin in treating SSHL. [1]
Alprostadil is a vasodilator that improves cardiovascular microcirculation, while mecobalamin is a form of vitamin B12. The study demonstrated that acupuncture and personalized herbal formulas achieved better treatment outcomes than the medication therapy control group.
In the study, one group received acupuncture and herbal medicine. Acupuncture treatments were administered every two days, and patients were given customized herbal formulas based on their traditional Chinese medicine (TCM) diagnostic patterns. The herbal medicine was prepared daily as a decoction from fresh herbs, divided into two servings (one in the morning and one at night). Prof. Liao, L.Ac., notes that two daily servings help maintain active herbal medicine ingredients in the bloodstream.
The control group received 10 μg of alprostadil (injection, once per day) and 500 μg of mecobalamin (tablets, three times per day). Both treatment courses lasted 14 days. The medication group had a 69.70% total effective rate, while the acupuncture and herbal group had a 91.00% total effective rate.
The acupuncture point prescription for the acupuncture and herbs group included:
- TB17 (Yifeng)
- TB21 (Ermen)
- SI19 (Tinggong)
- GB2 (Tinghui)
- TB5 (Waiguan)
- LI4 (Hegu)
- ST36 (Zusanli)
- SP6 (Sanyinjiao)
- KI3 (Taixi)
- GB20 (Taichong)
- GB44 (Zuqiaoyin)
Rapid needle insertion was performed. In the early stage of SSHL, the attenuation (xie) technique was used. In the late stage, the mild reinforcement and attenuation (ping bu ping xie) technique was applied. After achieving deqi (the arrival of qi), needles were retained for 30 minutes.
Herbal formulas were tailored based on different diagnostic patterns. For external contraction of wind (feng xie wai fan), a modified version of Yin Qiao San was used, including:
- Jin Yin Hua (15 g)
- Lian Qiao (15 g)
- Jie Geng (10 g)
- Fang Feng (10 g)
- Chai Hu (10 g)
- Xiang Fu (15 g)
- Chuan Xiong (10 g)
- Lu Gen (15 g)
- Chi Shao (10 g)
- Ge Gen (15 g)
- Gan Cao (6 g)
- Shi Chang Pu (10 g)
For liver fire flaming upward (gan huo shang yan), a modified version of Long Dan Xie Gan Tang was used, including:
Long Dan (12 g)
- Zhi Zi (12 g)
- Huang Qin (15 g)
- Dang Gui (15 g)
- Chai Hu (10 g)
- Sheng Di Huang (15 g)
- Ze Xie (10 g)
- Che Qian Zi (10 g, bagged)
- Yu Jin (10 g)
- Shi Chang Pu (10 g)
- Gan Cao (6 g)
- Ju Hua (12 g)
- Bo He (10 g, added last 5 minutes)
For Qi stagnation and blood stasis (qi zhi xue yu), a modified version of Tong Qiao Huo Xue Tang was used, including:
- Chi Shao (10 g)
- Chuan Xiong (10 g)
- Dan Shen (10 g)
- Shi Chang Pu (10 g)
- Chai Hu (10 g)
- Hong Hua (6 g)
- Lian Qiao (10 g)
- Dang Gui (10 g)
- Xiang Fu (9 g)
- Yu Jin (9 g)
- Lu Lu Tong (9 g)
- Ge Gen (10 g)
- Zhi Ke (10 g)
- Fo Shou (10 g)
- Gan Cao (6 g)
An independent study involving 50 patients with SSHL supported the findings, showing a 90.0% total effective rate for those treated with acupuncture. The acupuncture points used included:
- TB21 (Ermen)
- SI19 (Tinggong)
- GB2 (Tinghui)
- TB17 (Yifeng)
- TH3 (Zhongzhu)
- SP6 (Sanyinjiao)
- KI3 (Taixi)
Needles were immediately withdrawn from Ermen, Tinggong, and Tinghui after insertion, while for other points, needles were retained for 30 minutes with mild reinforcement and attenuation techniques applied every 10 minutes. Each course of treatment consisted of daily acupuncture for six days, followed by a one-day break, with three courses in total.
The study concluded that acupuncture reduces blood viscosity and enhances the deformability of red blood cells, thereby improving local blood circulation and aiding in the recovery of patients with SSHL. [2] This research provides both objective and subjective data supporting the use of acupuncture for treating sudden hearing loss.
Acupuncture For Tinnitus Relief
A study conducted by researchers at Luoding City Hospital of Traditional Chinese Medicine (Guangdong, China) found that acupuncture combined with the herbal formula Liu Wei Di Huang Wan effectively relieves symptoms and improves the quality of life for tinnitus sufferers. The study compared this treatment with hyperbaric oxygen therapy, revealing a 77.5% effective rate for the acupuncture and herbal group compared to 50% in the hyperbaric oxygen control group. [3]
Eighty patients with tinnitus and a TCM diagnosis of liver and kidney yin deficiency participated. They were randomly assigned to receive either acupuncture and herbs or hyperbaric oxygen treatment. The acupuncture group consisted of 23 male and 17 female patients (ages 45–67, mean age 54.3 years), with a disease duration of 1–12 years (mean duration 3.8 years). The control group included 24 male and 16 female patients (ages 46–70, mean age 55.4 years), with a disease duration of 2–13 years (mean duration 4.1 years). Both groups were comparable in baseline characteristics.
Control Group: Received hyperbaric oxygen treatment at 0.2 MPa, daily sessions of 80 minutes with two five-minute breaks. Each course included 10 treatments, with a total of 30 treatments.
Acupuncture Group: Prescribed Liu Wei Di Huang Wan (Shu Di Huang, Shan Zhu Yu, Shan Yao, Fu Ling, Mu Dan Pi, Ze Xie) at 6 grams twice daily. Acupuncture was administered on the affected side at:
- Tinggong (SI19)
- Tinghui (GB2)
- Ermen (TB21)
- Wangu (SI4)
- Fengchi (GB20)
- Taichong (LV3)
- Hegu (LI4)
- Zusanli (ST36)
- Shenshu (BL23)
Treatment involved using number 28 filiform needles with a balanced reducing-reinforcing technique. For excess patterns, a reducing method was used, while a reinforcing method was employed for deficiency patterns. Treatments were given daily, with one course comprising 10 treatments, for a total of 30 treatments.
Patients’ symptom severity, duration, and impacts on sleep, attention, and mood were measured. The acupuncture group showed significant improvements in all subcategories, with post-treatment scores indicating better outcomes than the control group. The acupuncture group had a total effective rate of 77.5%, compared to 50% in the control group.
This study suggests that acupuncture combined with Liu Wei Di Huang Wan is a more effective treatment for tinnitus due to liver and kidney yin deficiency than hyperbaric oxygen therapy, though results may vary.
Acupuncture and Electroacupuncture Alleviate Tinnitus
A clinical trial conducted by researchers from Shanxi Hospital of Acupuncture and Moxibustion and Shanxi University of Traditional Chinese Medicine investigated the effects of manual acupuncture and electroacupuncture on tinnitus. The study found that adding electrical stimulation (electroacupuncture) produced better patient outcomes than manual acupuncture alone. [4]
The electroacupuncture group achieved an 86.67% total efficacy rate, compared to 70% in the manual acupuncture group. The efficacy was measured using the Tinnitus Evaluation Questionnaire (TEQ) and blood flow velocity of the vertebral and basilar arteries. Both groups showed improvements, with more significant changes observed in the electroacupuncture group.
Participants were randomized into two groups: manual acupuncture and electroacupuncture. The electroacupuncture group consisted of 18 males and 12 females, aged 24 to 66 (mean age 45.87 ±11.52 years). The average disease duration was 8.73 ±4.26 months. The control group included 16 males and 14 females, aged 21 to 62 (mean age 41.87 ±12.70 years), with an average disease duration of 10.40 ±5.71 months. Symptoms included ringing in the ears, hearing loss, headaches, and anxiety.
Manual Acupuncture: Both groups received manual acupuncture with local and distal acupoints, including:
Local Ear Region Acupoints:
- TB21 (Ermen)
- SI19 (Tinggong)
- GB2 (Tinghui)
- TB17 (Yifeng)
- Distal Acupoints:
- TB3 (Zhongzhu)
- TB5 (Waiguan)
- GB43 (Xiaxi)
- KD3 (Taixi)
Mild reinforcing-attenuating manipulation was used, with patients in a supine position. Needles were inserted perpendicularly up to 25 mm, with patients keeping their mouths open during insertion.
Electroacupuncture: In addition to manual acupuncture, the electroacupuncture group received electrical stimulation at:
Local Ear Region Acupoints:
TB21 (Ermen) connected to GB2 (Tinghui)
TB17 (Yifeng) connected to SI19 (Tinggong)
Scalp Acupuncture: Center of the vertigo auditory area (1.5 cm above the ear tip, 4 cm wide), with needles placed at either end at a 15-degree angle to the skin surface. A disperse-dense wave frequency of 20 Hz was used, with moderate stimulation.
This study suggests that electroacupuncture offers enhanced outcomes for tinnitus treatment compared to manual acupuncture alone.
Sources:
[1] Li M, Shen HQ, Yang Y, et al. (2012). Clinical Observation on Chinese Medicine Combined with Acupuncture for 100 Cases of Sudden Deafness. Journal of Traditional Chinese Medicine, 53 (20), 1737-1738.
[2] Wang CH, Yang LW, Wang HC, et al. (2003). Effect of Acupuncture Treatment on Hemorheology in the Patient of Sudden Deafness. Chinese Acupuncture, 023(002), 87-88.
[3] Gan Mei (2019) “Clinical Observation on Treatment of Tinnitus with Liver and Kidney Yin Deficiency by Acupuncture Combined with Liu Wei Di Huang Pill,” Journal of Practical Traditional Chinese Medicine Vol.35 (2) p. 160.
[4] Wu Jinhui, Gao Shan, “Clinical Observation on Treating Tinnitus with Electroacupuncture,” Journal of Practical Traditional Chinese Medicine, 2023, Vol.39, No.1.
