ilmatiivis

Ilmatiivis is a Finnish adjective meaning airtight or hermetically sealed. It describes objects, joints, or materials designed to prevent the passage of air between the interior and the exterior. The word is formed from ilma (air) and tiivis (tight or sealed) and is used in everyday language as well as technical contexts such as packaging, storage, and construction.

In practical use, ilmatiivis implies that the object maintains an internal atmosphere, protecting contents from oxidation, moisture, or contamination, and limiting air exchange with the surroundings. It is commonly applied to containers, packaging materials, seals, films, and housings. The term is often encountered in consumer products (for example, airtight packaging) and in industrial or laboratory settings where controlled atmospheres are important.

In standards and industry, airtightness is typically described by leakage rates or results from pressure-change tests. Achieving ilmatiivis conditions may require components such as gaskets, seals, welding, or appropriate adhesives. The concept is closely related to, and sometimes used interchangeably with, terms like hermetic sealing and airtightness in technical documentation, though regional or disciplinary preferences may vary.

Etymology-wise, ilmatiivis derives from ilma (air) and tiivis (tight/sealed), reflecting its meaning as a state of being closed to air exchange. Common related phrases describe specific applications, such as ilmatiivinen pakkaus (airtight packaging) or ilmatiivinen säiliö (airtight container). See also hermetic seal and airtightness for broader context.