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Administrative Draft Environmental Impact Report Gill Medical Center Project Table 4.15-2 displays the reactions of people and the effects on buildings produced by continuous vibration levels.The annoyance levels shown in the table should be interpreted with care since vibration may be found to be annoying at much lower levels than those listed, depending on the level of activity or the sensitivity of the individual.To sensitive individuals,vibrations approaching the threshold of perception can be annoying. Low-level vibrations frequently cause irritating secondary vibration, such as a slight rattling of windows, doors, or stacked dishes.The rattling sound can give rise to exaggerated vibration complaints, even though there is very little risk of actual structural damage. In high-noise environments, which are more prevalent where groundborne vibration approaches perceptible levels, this rattling phenomenon may also be produced by loud airborne environmental noise causing induced vibration in exterior doors and windows. Table 4.15-2.Human Reaction and Damage to Buildings for Continuous or Frequent Intermittent Vibration Levels Peak Particle Approximate Velocity Vibration Velocity Human Reaction Effect on Buildings (inches/second) Level(VdB) 0.006-0.019 64-74 Range of threshold of perception Vibrations unlikely to cause damage of any type 0.08 87 Vibrations readily perceptible Recommended upper level to which ruins and ancient monuments should be subjected Level at which continuous 0.1 92 vibrations may begin to annoy Virtually no risk of architectural damage to normal people,particularly those involved buildings in vibration sensitive activities 0.2 94 Vibrations may begin to annoy Threshold at which there is a risk of architectural people in buildings damage to normal dwellings Vibrations considered unpleasant 0.4-0.6 98-104 by people subjected to continuous Architectural damage and possibly minor structural vibrations and unacceptable to damage some people walking on bridges Source: Caltrans 2020 Ground vibration can be a concern in instances where buildings shake, and substantial rumblings occur. However, it is unusual for vibration from typical urban sources such as buses and heavy trucks to be perceptible. For instance, heavy-duty trucks generally generate groundborne vibration velocity levels of 0.006 PPV at 50 feet under typical circumstances,which as identified in Table 4.15-2 is considered very unlikely to cause damage to buildings of any type. Common sources for groundborne vibration are planes, trains, and construction activities such as earth-moving which requires the use of heavy-duty earth moving equipment. Environmental Setting 4.15.2.2 Noise-Sensitive Land Uses Noise-sensitive land uses are generally considered to include those uses where noise exposure could result in health-related risks to individuals, as well as places where quiet is an essential element of their Noise 4.15-7 October 2021