【Reference】 In terms of the objects they control, clean rooms are divided into two major categories: industrial clean rooms and biological clean rooms.

The industrial clean room takes the control of non-biological particle contamination as its main purpose, while the biological clean room takes the control of biological particle contamination as its main purpose.

【Reference】 A biological clean room refers to a clean space in which suspended microorganisms in the air are controlled within specified values.

【Reference】 Since the objects of control are different, biological cleanroom technology has its own particularities; the differences between it and industrial cleanroom technology in essence and control mechanism can be concisely summarized in Table 1.5.

Table 1.5　Different control requirements of biological clean rooms and industrial clean rooms

Name Biological clean room Industrial clean room
Typical application fields Medical care, pharmaceuticals, food, laboratory animals, biosafety and other fields High-purity materials, microelectronics (e.g., integrated circuits), precision instruments, aerospace, etc.
Particle properties Microorganisms are living particles that can reproduce. They usually form colonies, with a relatively larger equivalent particle diameter Most dust particles have smaller diameters and higher concentrations. Some processes also pay attention to the chemical properties of dust
Particle control objectives Control microbial contamination or harm, with greater emphasis on eliminating hidden dangers of bacterial growth in the system Control the particle diameter and concentration of dust, with emphasis on the protection of process production
Particle control requirements The allowable microbial concentration in the air is determined by the requirements of the quality control system The controlled particle diameter is generally taken as 1/3 of the characteristic line width or smaller
Impact of particles on processes Aseptic processes do not allow contamination by even a single microbial particle; for general processes, biological particles must reach a certain concentration to constitute a hazard A single particle at a critical location can ruin an entire integrated circuit
Characteristics of controlled particles Particles that can cause a one-time harm to aseptic process control are, for general processes, a kind of cumulative harm particle (Progressive failure particle) The particle diameter of "killer particles (Killer particles)" that can cause fatal damage to the process
Control parameters Indoor microbial concentration (purification measures are only a means) Indoor cleanliness class