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Limit sound volume
Published in Michael Wiklund, Kimmy Ansems, Rachel Aronchick, Cory Costantino, Alix Dorfman, Brenda van Geel, Jonathan Kendler, Valerie Ng, Ruben Post, Jon Tilliss, Designing for Safe Use, 2019
Michael Wiklund, Kimmy Ansems, Rachel Aronchick, Cory Costantino, Alix Dorfman, Brenda van Geel, Jonathan Kendler, Valerie Ng, Ruben Post, Jon Tilliss
Noise-canceling headphones are a great tool for reducing the consequences of constant exposure to loud sounds, such as those experienced by private pilots in single engine aircraft. Noise-canceling headphones work by using a microphone to detect ambient sounds, and then using electronics in the ear piece to generate noise-canceling waves that are 180° out of phase with the ambient noise waves, effectively “erasing” the ambient sounds.8 Manufacturers now also apply noise-canceling technology that reduces noise at the source, eliminating the need for people to wear noise-cancelling headphones or hearing protection.
Effects of audiovisual stimuli on psychological and psychophysiological responses during exercise in adults with obesity
Published in Journal of Sports Sciences, 2019
Marcelo Bigliassi, João P. A. Greca, Vinícius Barreto-Silva, Priscila Chierotti, Arli R. de Oliveira, Leandro R. Altimari
Deprivation of auditory signals was ensured by using cottonball earplugs and noise cancelling headphones. Thus, the auditory sensory signals were blocked, forcing attentional focus towards internal sensory cues. Researchers asked three personal questions (e.g., what is your name?) at ~90 dBA and 50 cm from the participant’s ears to ensure complete blockage of auditory processing. In case of positive response, the research team applied stretchable elastic straps over the headphone to further improve auditory deprivation. The imposed exercise awareness was expected to increase the use of associative thoughts, upregulate fatigue-related symptoms, and make the exercise less enjoyable (Boutcher & Trenske, 1990).
Effects of vertical vibration on sitting comfort in civil aviation during the cruising flight
Published in Ergonomics, 2023
We installed a rigid aluminium seat (685 × 480 × 1110 mm) with a seat back and armrests on the vibration table. Subjects sat upright with the safety belt fastened (effective length 1.3–1.75m) (Figure 2). They kept their thighs and knees at the same height, and an adjustable rigid horizontal footrest was employed to remain in the positions of their thighs and knees. They wore a pair of earplugs and a pair of noise-cancelling headphones (QC25, Bose, America) to isolate the noise during the experiment. The sound pressure level of background noise was less than 58.5 dB(A), measured via the artificial head (HEAD HMS IV, Germany) under the headphones when the vibrator was running.
Discomfort estimation for vertical whole-body vibration in the aircraft cabin considering the duration and static sitting comfort
Published in Ergonomics, 2023
Subjects sat upright and wore seat belt (effective length 1.3–1.75 m). Their thighs and knees were kept at the same height during the test. An adjustable rigid horizontal footrest was employed to keep the height and horizontal angle of their thighs and knees when necessary, as shown in Figure 2. A pair of earplugs (3 M 1110, USA) and a pair of noise-cancelling headphones (QC25, Bose, USA) to avoid auditory interference by mechanical noise. The sound pressure level of background noise was <58.5 dB(A) when the vibrator was running, measured using the artificial head (HEAD HMS IV, Germany) wearing headphones.