Clean spaces are defined as areas in which particle concentration and environmental conditions are controlled at or within specified limits. Design of clean spaces (or cleanrooms) covers much more than traditional control of air temperature and humidity. Additional factors may include control of particle, microbial, electrostatic discharge (ESD), molecular, and gaseous contamination; airflow patterns; air pressurization; sound and vibration; environmental health; life safety; industrial engineering aspects; and manufacturing equipment layouts. The objective of good cleanroom design is to maintain effective contamination control while ensuring required levels of reliability, productivity, installation, and operating costs. Terminology Clean Spaces and Cleanroom Applications Airborne Particles and Particle Control Air Pattern Control Airflow Direction Control Between Clean Spaces Testing Clean Air and Clean Spaces Pharmaceutical and Biomanufacturing Clean Spaces Start-Up and Qualification of Pharmaceutical Cleanrooms Semiconductor Cleanrooms High-Bay Cleanrooms Environmental Systems Sustainability and Energy Conservation Noise and Vibration Control Space Construction and Operation Cleanroom Installation and Test Procedures Integration of Cleanroom Design and Construction Life and Property Safety