Compartmentation

Compartmentation refers to the division of a system into separate, enclosed compartments that restrict the movement of substances, energy, or information between them. The concept is used to improve control, safety, efficiency, and security by limiting interactions across barriers that separate regions or components.

In cells, compartmentation describes the organization of biochemical processes into organelles and other membrane-bound or membrane-less regions. This separation creates distinct environments—for example, the acidic interior of lysosomes or the high-ionic milieu of mitochondria—that enable specific reactions to proceed while protecting other cellular components. Examples include the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, peroxisomes, and chloroplasts in plants. Beyond organelles, subcellular compartments include vesicles, microdomains, and protein complexes. Benefits include enhanced metabolic efficiency, regulation of signaling, and protection from toxic intermediates.

In engineering and facilities design, compartmentation uses fire-rated barriers and controlled voids to limit the spread of fire, smoke, and hazardous substances. Building codes specify compartment boundaries that create fire-resistance ratings, smoke barriers, and egress paths to maintain safe operation during incidents. Similar ideas apply in chemical plants and laboratories to contain spills and control cross-contamination.

In information security and defense, compartmentation limits access to information by designing systems with least-privilege and need-to-know constraints. Data and processes are separated into compartments with controlled interfaces, and sensitive operations may be performed in isolated environments or using "compartmented mode of operation." The approach reduces risk by preventing a single breach from exposing all assets.

Other uses include military or industrial design practices where critical components are physically or logically separated to reduce risk.