Source: Handbook of Noise Control, 2 nd Ed. Use insert type or over-ear earphones in helmet or in muffs good to 120 dB(A) on short-term basis

Use any in muff or helmet except bone conduction type Type of earphone to supplement loudspeaker Use press-to-talk switch and an acoustically treated booth Very difficult to impossible, even at a distance of 1 cm Maximum voice level at distances up to 25 cm Very loud or shouted voice level at distances up to 50 cm Raised voice level at distances up to 2 m Speech Communication Capability versus Level In such cases noise level should not exceed 55 to 60 dB(A). In social situations people often talk at distances of 2 to 4 meters. In noisy work situations - level of noise as high as 78 dB(A) - people can converse at a distance of one meter, but with difficulty and for a short time.įor prolonged conversations, the background noise level must be lower than 78 dB(A). People with otherwise unnoticeable hearing loss find it difficult to understand spoken words in noisy surroundings. The sound level of speech must be greater than the background noise at our ear for us to understand what we hear. The noise also prevents individuals from hearing work instructions and warning/danger signals. Surrounding or background noise makes difficult to understand what other people are saying during face to face or telephone conversations. Speech intelligibility is the ability to understand spoken words. Below are some examples of how these factors can affect work performance. Noise can interfere with verbal communications and can be stressful, distracting and annoying. How can noise affect performance? Back to top Changes in the diameter of the blood vessels, particularly in the skin.Īll of these effects are similar to the body’s response to other stressors.The respiratory reflexes, where the respiratory rhythm tends to change when noise is present.The muscle tension response, where muscles tend to contract in the presence of loud noise.The startling response to loud noise, where muscles burst into activities, generally, with the intention to protect.The physiological effects can be temporary or permanent.Įxamples of temporary physiological effects are: What are some examples of physiological effects? Back to top Non-auditory effects can be divided into two categories - physiological effects and performance effects. What types of non-auditory effects are there? Back to top While there are many studies about environmental noise exposure of the community and children, these exposures are not the focus of this document.

Note that this document focuses on non-auditory effects on individuals in workplaces. In the workplace, non-auditory effects of noise also include problems with oral communications. The non-auditory response to noise may depend on the characteristics of the sound including intensity, frequency, predictability, the complexity of sound, duration (length of exposure), and the meaning of the noise. This wide range of effects has led researchers to believe that noise can act as a general, non-specific stressor. Reported non-auditory effects of noise include increased stress, cardiovascular function (hypertension, changes to blood pressure and/or heart rate), annoyance, sleeping problems, and mental health. Hearing loss from long term exposure to noise has been recognized as a hazard for a long time. What are non-auditory effects? Back to top You are here: Noise - Non-Auditory Effects

Auditory synonym