The cleanliness of the parts of maintenance before sterilization
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The parts of maintenance in contact with pharmaceutical products or medical must be the object of regular cleanings in order to guarantee the constancy of the process. In Addition To the sterilization which makes it possible to avoid the biological contamination, other residues on surfaces must be withdrawn. |
According to the contamination to be withdrawn (grease, residues of powder…), several techniques of cleaning are presented to find the good compromise enters on and under quality. In order to qualify the cleanliness of the parts after cleaning, different measurement technique are presented.
1 What to clean?
1.1 Parts of maintenance
The parts of maintenance are defined like all parts in contact with the products (cap, filter, mould…) who are dismounted equipment of production.
The constitutive materials are of all kinds:
- Metal: in the majority of the cases, the parts are massive and out of stainless steel or aluminum.
- Plastic: the polyfluorés polyethylenes, polyacrylates and (PTFE, PFA) are the principal plastics used. (PE) (PA)
- Ceramics: glasses and sintered ceramics are sometimes used for small parts.
Dimensions of the parts can be of all sizes going from screws and bolts (a few cm ²) to bonnet covers (1m ²); just as the geometry can be in two dimensions (caps) until complex forms such as the filters (figure attached).
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1.2 Contaminations
The studies the “Extractable ones & Leachables” inevitably any more do not relate to packing of the drugs but also surfaces of materials in contact with the parts during the manufacturing.
The particles (> 0.1 µm) represent the majority contamination because generally they are visible with the eye. They can be of all natures such as the dust of drugs or environment or staff.
Other species on the surface of the parts of maintenance can generated contaminations of contact with the products. Residual metals are distinguished (of which “Big Four”, As, Cd, Hg, Pb), the ions (residues of solutions ammonia, acids, bases) and the organics (grease, oil, solvent…).
2 techniques of cleanings
Cleaning must be adapted according to materials and of the contaminations to be withdrawn. The following table shows the usual techniques of cleanings:
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The rinsing and drying are the stages according to cleaning. They will be carried out preferably in classified clean room ISO 6 or 7 according to the ISO standard 14-644. Packing and storage are also key stages to take care of the good process of cleaning.
This process must conform to the criteria of cleanliness required in order not to realize on or of under quality.
3 the measurement of cleanliness
To qualify the cleanliness of surfaces of the parts of maintenance, several methods can be under consideration according to the family of contamination.
Thus to measure the particulate contamination it can be used either a radiation counter on surfaces, or a radiation counter in the liquids. The first measurement is fast and easy to use but gives a relative result. The second measurement is more complex to implement with an immersion of the part in water, the use of the ultrasounds to take down the particles and to put them in solution to be counted. This method of measurement has the advantage of being absolute than the first. Thus, during cleaning in room ISO 6, surface counting gives a number of particles >1µm of 0/cm ² whereas voluminal counting gives 200,000 part/cm ².
The measurement of the chemical contaminations (metal, ionic and organic) is generally carried out by immersion in a solvent adequate and the extracted liquid is analyzed by the adapted techniques of analysis, cf following table.
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4 Conclusion
The cleanliness of the parts of maintenance must be supervised because only sterilization does not make it possible to withdraw all the contaminations which can be present in the pharmaceutical products.
 Pièce en acier inoxydable: Avant / Après nettoyage |
 Pièce acier inoxydable: Avant / Après nettoyage |
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Séverine Blanc - 40-30 |
