Puhastustaset

Puhastustaset is a Finnish term used to describe the level of cleanliness in environments where contamination must be minimized. The concept covers air purity, surface cleanliness, humidity, temperature, and personnel hygiene, and it is applied in sectors such as pharmaceutical manufacturing, electronics, medical devices, healthcare facilities, and food processing.

The level of cleanliness is typically measured by particle counts per unit volume and, in some contexts, by microbial load. Common practice involves specifying the allowed concentration of particles of certain sizes (for example, 0.5 micrometers and larger) and regularly sampling surfaces and air. International standards, especially ISO 14644, provide a framework for classifying cleanrooms and other controlled environments; Finnish regulations and industry guidelines generally follow these international classifications. Puhastustaso is achieved and maintained through a combination of architectural design, controlled ventilation (often with HEPA or ULPA filtration), pressure differentials, smooth and easily cleanable surfaces, and disciplined operating procedures.

Implementation typically includes routine cleaning protocols, validated cleaning agents, gowning and personal hygiene requirements for staff, and ongoing monitoring of environmental conditions such as particle counts, air changes per hour, temperature, and humidity. Training and documentation are emphasized to ensure consistency and compliance across shifts and facilities. The concept of puhastustaso is thus both a design criterion and a management practice aimed at safeguarding product quality, patient safety, and regulatory compliance.

See also: cleanroom, ISO 14644, environmental hygiene.