Chemical sterilizers, also known as chemosterilants or liquid chemical germicides, are powerful chemical solutions used to achieve high-level disinfection or sterilization of heat-sensitive medical instruments and devices that cannot withstand the high temperatures of autoclaving. Common chemical sterilants include glutaraldehyde, orthophthalaldehyde (OPA), and hydrogen peroxide. These chemicals work by denaturing proteins and disrupting cellular structures of microorganisms, including spores, given sufficient contact time. Instruments are typically immersed in the solution for a specified period, followed by thorough rinsing with sterile water to remove chemical residues. Chemical sterilizers are crucial for reprocessing endoscopes, respiratory therapy equipment, and other delicate instruments, playing a vital role in preventing healthcare-associated infections when heat sterilization is not feasible. Proper ventilation and handling precautions are essential due to the potent nature of these chemicals.