Lowsmoke

Low-smoke refers to materials that are formulated to emit relatively little smoke when burned. The term is used for a range of products, including plastics, cables, coatings, and insulation. In a fire, smoke can reduce visibility and hinder evacuation, while inhalation of smoke and toxic gases can be deadly. Low-smoke materials aim to reduce smoke density and, in some cases, limit the release of toxic compounds, improving safety in enclosed or occupied spaces.

Common implementations include low-smoke, halogen-free cables and jackets, often marketed as LSZH or similar variants. These are designed to emit minimal smoke and little or no halogen acids when exposed to flame. Other low-smoke formulations appear in foams, coatings, and insulating materials used in construction, electrical equipment, and furniture. While the focus is on reducing smoke, some formulations also seek to limit toxic gas production, though this depends on the specific chemistry.

Applications and standards vary by region but often target environments with high occupant density or restricted egress routes, such as aircraft, trains, ships, hospitals, offices, and data centers. Building codes, transport safety requirements, and industry standards commonly mandate testing of smoke density, flame spread, and toxicity to classify materials for use in specific spaces.

Testing and classification rely on standardized laboratory methods that measure smoke opacity, density, and the release of toxic gases under controlled flame conditions. Materials are rated accordingly to guide procurement and installation decisions. Limitations include higher cost, potential trade-offs with mechanical properties, and unfinished performance in some real-world fire scenarios; ongoing certification ensures compliance with applicable safety standards.