Laboratories may generate hazardous gases during chemical reactions, sample preparation, heating, digestion, synthesis, and analytical testing. Effective gas collection is essential for protecting laboratory personnel, preventing environmental contamination, and maintaining a safe working environment. The appropriate collection method should be selected according to the gas properties, concentration, generation rate, and laboratory process.

The most common method is local exhaust ventilation, particularly through a chemical fume hood. A fume hood captures hazardous gases directly at the source and removes them through a dedicated exhaust system. It is widely used for volatile organic compounds, corrosive vapors, toxic gases, and chemical reactions that may release harmful fumes.

For processes requiring more targeted capture, local exhaust arms and extraction hoods can be installed close to the emission point. These systems are useful for instruments, reaction vessels, furnaces, and other equipment that continuously produces gases.

When gases require treatment before discharge, laboratories may use gas scrubbers. Wet scrubbers can remove soluble or reactive gases, while dry scrubbers and adsorption systems use materials such as activated carbon or specialized sorbents to capture specific contaminants. Activated-carbon filtration units are particularly useful for certain organic vapors.

Common supporting equipment includes exhaust fans, ductwork, gas collection chambers, filtration units, scrubbers, adsorption columns, gas detectors, and alarm systems. Continuous monitoring with toxic-gas or oxygen-deficiency detectors can provide early warning when hazardous concentrations occur.

A complete hazardous-gas control system should combine source capture, appropriate filtration or treatment, reliable ventilation, regular inspection, and routine maintenance. Proper equipment selection and periodic performance testing are critical for ensuring safe and effective laboratory operation.