Chemicals hazards include health effects, such as irritation, target organ toxicity and carcinogenicity, and physical effects, such as flammability and corrosion.  It is important to understand the hazards of the chemicals that you work with so that you can control your exposure to the hazard.  The Occupational Safety and Health Administration (OSHA) sets permissible exposure limits (PELs) for some workplace chemicals.  These limits are found in 29CFR1910.1000.  Other groups, such as the American Conference of Governmental Industrial Hygienists (ACGIH) also provide exposure guidelines, called Threshold Limit Values (TLVs), that are updated frequently and reflect conditions a worker can be exposed to over their lifetime with no health effect.  Information on the health and physical hazards of a chemical can be found on chemical labels and in safety data sheets (SDSs).   Chemical hazards should be controlled by eliminating the chemical or substituting a less hazardous chemical, using engineering controls and work practices, and finally using appropriate personal protective equipment (PPE).