Problem 1: Number of chromosomes. A human cell has 46 total or 23 pairs of chromosomes. Following mitosis, the daughter cells would each have a total of ______ chromosomes. After meiosis I, the two daughter cells would have _____chromosomes, and after meiosis II ______ chromosomes.
The permissible exposure limit (PEL or OSHA PEL) is a legal limit in the United States for exposure of an employee to a chemical substance or physical agent.For chemicals, the chemical regulation is usually expressed in parts per million (ppm), or sometimes in milligrams per cubic meter (mg/m 3). TWA is the average exposure over a specified period of time, usually a nominal eight hours. This means that, for limited periods, a worker may be exposed to concentration excursions higher than the PEL, so long as the TWA is not exceeded and any applicable excursion limit is not exceeded.
Occupational - Various organizations set standards for occupational exposure limits to beryllium. The. United States Occupational Safety and Health Administration, or OSHA has established standards that limit. the amount of airborne beryllium particles to which a person may be exposed. California OSHA has also. established standards that limit the amount of airborne beryllium particles to which a person may be. exposed. The National Institute for Occupational Safety and Health (NIOSH) is a scientific body which. recommends occupational exposure limits to many substances.