Vibration in the occupational and general environmental settings can be manifested in many ways according to frequency, magnitude, or medium and subsequent effects on the human body. Frequency ranges with potential risk to humans can range from less than one cycle per second (Hertz - Hz) to hundreds of thousands. The vibration ranges to be considered are Whole Body Vibration ranging from 0.5 to 80 Hz and audible sound from 20 to 20000 Hz. Both WBV and noise are acknowledged as having potential to causing harm to the human body.
Safety and health (SH) professionals address hazards through anticipation, recognition, evaluation, and control. The anticipation and recognition of noise hazards can be considered a basic skill set among SH professionals. With the human sense of hearing, we are much attuned to noise in our environments. What is more difficult for the human sense of hearing is the ability to quantify the magnitude of sound. People can categorize sound or its unwanted companion noise as low, moderate, loud, or very loud, but generally fail in attempting to accurately estimate exposures in decibels (dB). Most SH professionals should know the guide to assess if a noise environment is exceeding 85 dB - do you have to raise your voice to be heard at arm's length? This approach is not an accurate means of noise measurement and surely would not stand the scrutiny of an OSHA compliance officer responding to a noise complaint in the workplace. However, this basic technique can satisfy to hazard assessment levels of anticipation and recognition for noise.
WBV is even more difficult for people to assign quantified magnitudes than with noise. While seated in a vehicle seat, such as a forklift traversing a construction site, the human operator can qualitatively describe a smooth, bumpy, or rough ride. However, it would be extremely unlikely that the operator could closely approximate the intensity in terms of actual acceleration in meters per second squared (m-s-2) within the frequency range of 0.5 to 80 Hz.
