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). short-term exposure limit is one that addresses the average exposure over a 15-30 minute period of maximum exposure during a single work shift.
Abraham Lincoln became the United States' 16th President in 1861, issuing the Emancipation Proclamation that declared forever free those slaves within the Confederacy in 1863.
Abraham Lincoln (February 12 1809 â April 15 1865) was the 16th President of the United States. He served as president from 1861 to 1865, during the American Civil War. Just five days after most of the Confederate forces had surrendered and the war was ending, John Wilkes Booth assassinated Lincoln. Lincoln was the first president of the United States to be assassinated. Lincoln has been remembered as the Great Emancipator because he worked to end slavery in the United States.