NIOSH does not develop permissible exposure limits. Permissible exposure limits, or PELs, are created by OSHA. OSHA follows a rigorous and lengthy process required of all Federal Regulators. They:
The permissible exposure limit for respirable dust containing crystalline silica is 0.05 mg/m3 as recommended by the National Institute for Occupational Safety and Health (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH). This limit is intended to protect workers from the health risks associated with exposure to crystalline silica, which can cause silicosis and other respiratory diseases.
Both OSHA and NIOSH were created by the Occupational Safety and Health Act of 1970.
You cannot measure exactly the sound pressure level of the noise. It will change a bit. You cannot decide the allowable sound pressure level exactly on the minute. It depeds on the listening person. Some are more sensitive and some are less. "Permitted Exposure Time Guidelines - SPL" Sound pressure level Lp and permissible exposure time t: 115 dB = 0.46875 minutes (~30 sec) 112 dB = 0.9375 minutes (~1 min) 109 dB = 1.875 minutes (< 2 min) 106 dB = 3.75 minutes (< 4 min) 103 dB = 7.5 minutes 100 dB = 15 minutes 97 dB = 30 minutes 94 dB = 1 hour XXX 91 dB = 2 hours 88 dB = 4 hours 85 dB = 8 hours 82 dB = 16 hours Lower dBs are said to be harmless Accepted standards for recommended permissible exposure time for continuous time weighted average noise, according to NIOSH (National Institute for Occupational Safety and Health) and CDC (Centers for Disease Control and Prevention) in 2002. For every 3 dBs over 85dB, the permissible exposure time before possible damage can occur is cut in half.
The National Institute for Occupational Safety and Health is participating in an international effort of research groups, government agencies and industries seeking to understand the health impact of nanotechnology and how to control potential risks. NIOSH is pursuing a number of initiatives, including: • Studying the mechanisms leading to nanoparticle toxicity. • Developing and testing methods to characterize and monitor the healthrelated properties of nanomaterials. • Investigating nanoparticle exposure and ways of controlling exposure in the workplace Through strategic planning, working in partnership with others and making information widely available, NIOSH is working in parallel with the development and implementation of nanotechnology to fulfill its mission of providing national and world leadership to prevent work-related illness and injuries.
The purpose of NIOSH (National Institute for Occupational Safety and Health) is to conduct research and provide recommendations to prevent work-related injuries, illnesses, and fatalities. NIOSH also offers training and educational resources to help improve occupational safety and health practices.
Niosh
The Occupational Safety and Health Administration (OSHA) has set the permissible exposure limit (PEL) for tantalum exposure in the workplace as 5 mg/m3 over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 5 mg/m3 over an 8-hour workday and a short-term limit of 10 mg/m3. At levels of 2500 mg/m3, tantalum is immediately dangerous to life and health.
OSHA, NIOSH and the Occupational Safety and Health Review Commission (OSHRC) were all established by the Occupational Safety and Health Act of 1970. OSHA issues the regulations and inspects to enforce them. NIOSH researches safety and health and recommends safety and health standards. The OSHRC reviews contested OSHA citations.
True
It is a measure of the opacity of smoke. Ringlemann grid cards run from 0 - all white smoke to 5- all black smoke. See Bureau of Mines Circular ic8333, a link to it is available on the NIOSH site at: www.cdc.gov/Niosh/mining/pubs/pubreference/outputid330.htm
A NIOSH-approved respirator with organic vapor cartridges is recommended for working with polyurethane.
The ear drums are moved by the sound pressure deviations only. Therefore don't ask for sound intensity. Sound pressure is measured by an SPL meter. Very loud noise is aching. The "threshold of pain" has the value of about 130 dB Sound Pressure Level (SPL). "Permitted Exposure Time Guidelines - SPL" Sound pressure level Lp and permissible exposure time t: 115 dB = 0.46875 minutes (~30 sec) 112 dB = 0.9375 minutes (~1 min) 109 dB = 1.875 minutes (< 2 min) 106 dB = 3.75 minutes (< 4 min) 103 dB = 7.5 minutes 100 dB = 15 minutes 97 dB = 30 minutes 94 dB = 1 hour 91 dB = 2 hours 88 dB = 4 hours 85 dB = 8 hours 82 dB = 16 hours Lower dBs are said to be harmless There are accepted standards for recommended permissible exposure time for continuous time weighted average noise, according to NIOSH (National Institute for Occupational Safety and Health) and CDC (Centers for Disease Control and Prevention) in 2002. For every 3 dBs over 85 dB, the permissible exposure time before possible damage can occur is cut in half.