In our cleanroom series today, we are looking at the people who work in the cleanroom and the requirements and standards of behavior that they must meet.
We have both ISO 8 and ISO 7 cleanroom areas, which must also fulfill GMP sterility requirements. Working in a cleanroom always requires a clothing and training concept based on the ISO class as well as corresponding rules of conduct. As humans always represent the greatest risk of contamination in a cleanroom, the aim is to automate as many processes as possible and only carry out the most necessary manual operations.
High ISO class = strict requirements
The higher the cleanroom class, the stricter the clothing and conduct regulations. These requirements are regulated in the cleanroom standard DIN EN ISO 14644. The clothing rules for our ISO 8 areas are as follows: Coat over own clothing, overshoes or cleanroom shoes, a hood to cover hair, and a beard protector if necessary. The process starts at the top with the hood and goes down to the shoes. The person then moves to the clean side of the airlock via a sit-over bench inside the personnel airlock. The aim is to minimize the particles entering the ISO 8 cleanroom. The regulations increase significantly when moving on to our ISO 7 cleanrooms: A full-body overall with cuffs on the arms and legs is required to prevent particles from escaping, along with a hood, face mask, cleanroom shoes, and gloves, which must be pulled over the cuffs of the suit. When putting on the sterile-packed overalls, it must never be allowed to touch the floor and must only be touched from the inside so that no particles get onto the outside. The frequency of clothing changes is also important. For example, overalls for the ISO 7 cleanroom are cleaned and reprocessed after each wear, while ISO 8 coats can be used again.
Individual risk assessment for each product
In addition to these general clothing rules set out in the standard, a specific risk assessment is carried out for each product manufactured in a cleanroom to determine which additional measures and clothing, behavioral, training, and cleaning concepts are required in each case. If the end product comes into direct contact with the patient, for example, stricter precautions are required.
Avoiding rapid movements
In addition to the right clothing, trained behavior is also important in the cleanroom. In general, no fast, jerky movements should be made in the cleanroom so as not to stir up particles. Conversations should be kept to a minimum and sneezing or coughing is only permitted in the crook of the arm or, if possible, outside the cleanroom. If employees have a cold, they are not allowed to work in the cleanroom for the duration of their illness. Similarly, for some products, e.g. test cartridges for certain pathogens, people who carry this pathogen must not be involved in the production process in the cleanroom in order to avoid producing a false-positive product batch (e.g., PCR tests for the detection of SARS-CoV-2 pathogens).
Regular mandatory training
In principle, there are technical access barriers to our cleanroom areas. Only trained employees can enter the ISO 7 rooms via their chip and some ISO 8 areas also have access requirements.
Training courses are held at fixed intervals. This is stipulated in the standard and also specified in the respective risk assessment for a product. This includes initial training when new employees start working in the cleanroom, as well as hygiene training, cleaning training, and GMP training for products that require sterility and the absence of particles.
Cleanroom cleaning
Even if no dirt appears to be visible, the cleanrooms must be cleaned at individually defined intervals. Special cleaning agents, equipment, and techniques are used for this purpose. Depending on the requirements, we use external service providers who clean general areas in the cleanrooms according to a fixed cleaning plan, while our own employees clean the systems in the cleanroom, which require a keen eye for system components and functionalities. For the large ISO 8 surfaces, we rely on our cleaning robot – an experienced colleague with whom particles don’t stand a chance.
A matter of common sense
Our Head of Quality Assurance Dr. Sabine Feicht and our Technical Manager Josef Hofmann stress that what may sound like strict regulations and complicated rules is actually a matter of common sense, such as not working when sick. Employees very quickly internalize how to prevent particles from entering the cleanrooms and how to manufacture high-quality medical products even under special conditions.
