RKT Editorial Team in collaboration with
Quality Assurance Management
Cleanroom Production to ISO 8 and ISO 7
Reading time: 2 min
Owing to our focus on medical technology, diagnostics, and life science, roughly 70 percent of production at RKT already takes place under cleanroom conditions of ISO Class 8. Higher requirements are met with our ISO 7 cleanrooms enclosed within the ISO 8 area (shell principle). But what exactly do the ISO classes mean, and which components have to be manufactured under which conditions?
Among others, we provide intensive consulting to start-ups with little industrial manufacturing experience who come to us with a product idea—covering production planning, the structuring of processes, and cleanroom requirements. Our quality assurance team is always involved in this and begins advance quality planning at an early stage, for example by also carrying out an FMEA (Failure Mode and Effects Analysis), which includes cleanroom planning, among other things.
Permitted Particle and Germ Counts
The ISO class of production has to be clarified; it differs primarily in the permitted number of particles in the air (ISO 8: 3,520,000 particles of 0.5 µm/m³ of air; ISO 7: 352,000 particles of 0.5 µm/m³ of air). In addition, there is the consideration of whether GMP criteria must also apply. These concern a possible microbial load within the cleanroom cell. Analogous to ISO Class 7 is GMP Class C, in which microbiological monitoring is carried out by means of so-called contact plate samples on surfaces distributed around the room. Here, no more than 25 CFUs per contact plate (55 mm diameter) may be detected (CFU = colony-forming units).
Airlock Procedure
Apart from the permitted particle and germ counts, ISO 8 and ISO 7 cleanrooms differ less in their filter and fan systems than, above all, in the airlock-in procedure and in the behavioral rules regarding hygiene requirements. While for ISO 8 long clothing, a cleanroom coat, a hairnet, and overshoes are sufficient, the ISO 7 cleanroom requires a special clothing concept in which a full-body suit, shoes, gloves, and safety goggles have to be donned in a prescribed manner.
Which components require which cleanroom class cannot be answered across the board. In principle, medical products in which a germ or particle load could harm a patient require high ISO classes and, where applicable, manufacturing in accordance with GMP specifications. Through subsequent sterilization of the finished product, production in the ISO 8 area can also be implemented with an appropriate hygiene concept.
