rus
Issue #5/2021
D.P.Melnik, A.K.Rybakov, A.V.Gospodinov
Qualification and certification of clean steam production and distribution systems
Qualification and certification of clean steam production and distribution systems
DOI: 10.22184/1993-8578.2021.14.5.284.290
The paper describes technical details of a relatively complicated qualification procedure of clean steam production and distribution systems. The authors propose a test kit – KIT ASEPTICA CLEAN STEAM intended for qualifying the clean steam system.
The paper describes technical details of a relatively complicated qualification procedure of clean steam production and distribution systems. The authors propose a test kit – KIT ASEPTICA CLEAN STEAM intended for qualifying the clean steam system.
Теги: clean rooms clean steam clean steam distribution systems системы распределения чистого пара чистые помещения чистый пар
Qualification and certification of clean steam production and distribution systems
INTRODUCTION
In accordance with Appendix No. 15 GMP, the production and distribution system "Validatsia" [1] is critical and must be qualified. The methods of qualification are described in details in PIC/S recommendations [4]. Qualification is carried out in three stages, IQ, OQ, and PQ.
Steam dryness, steam superheating, noncondensing gases, and condensate electrical conductivity are the normalized parameters important for the sterilization quality.
TERMS AND DEFINITIONS
Clean Steam means a steam produced in a specialized steam generator from the conditioned drinking water which condensate meets, according to the Pharmacopoeia the quality criteria of "water for injections". Basically, it is used in medicine, electronics and food production.
Steam humidity means the ratio of the dropping liquid contained in a saturated steam to the total quantity of the mixture of phases.
Noncondensing gases mean air and other gases, which are not condensed under the steam sterilization conditions.
Superheated steam means a steam heated to a temperature, exceeding the boiling point at a given pressure.
CLEAN STEAM SYSTEM
The rules of design and assembly of clean steam systems are described in the ISPE Guideline "Baseline Pharmaceutical Engineering Guide for New and Renovated Facilities", volume 4 "Water and Clean Steam Systems" [3].
It is strongly recommended to indicate the bleed clean steam points both for monitoring needs and for steam qualification.
Bleed points are arranged at a steam generator inlet and near each steam consumer. Three main factors can affect the steam quality:
See below the steam bleeding diagrams in accordance with GOST and their implementation by using a KIT ASEPTICA CLEAN STEAM for qualifying the clean steam systems.
Steam dryness
Steam sterilization requires a continuous supply of dry saturated steam.
Excessive humidity, transferred in the aerosol form can lead to overwatering load, whereas too low humidity cannot prevent the steam transformation into the superheating steam when it is expanded in a sterilization chamber. It is hard to accurately measure the moisture content percentage and the traditional methods require a continuous steam jet and cannot be used in sterilizers. The testing method described below should be considered as a demonstration of a good quality of a steam, not as an instrument for measuring a real content of moisture in steam.
Steam superheating
Checking steam for superheating must show that a quantity of moisture transferred with a steam is sufficient (not sufficient) to prevent transformation of a saturated steam to the superheated steam at its expansion in a sterilizer chamber.
Noncondencing gases
Checking a steam quality and the content of noncondensing gases must show that the noncondensing gases content level contained in a steam does not prevent achievement of sterilization conditions in any part of the sterilizer loading. This checking method can be considered as a demonstration of a good quality of a steam, not as an instrument for measuring of a real content of noncondensing gases in a steam.
Electrical conductivity of condensate
When bleeding samples of clean steam, it is necessary to remember the following:
The kit consists of:
CONCLUSIONS
It is important that throughout the entire process of distribution and supply of steam, it has been produced and maintained in a high quality condition. Therefore, clean steam must comply with strict requirements that depend on the final application.
Engineers of LLC "VALIDATION LABORATORY ASEPTICA" propose:
Declaration of Competing Interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
INTRODUCTION
In accordance with Appendix No. 15 GMP, the production and distribution system "Validatsia" [1] is critical and must be qualified. The methods of qualification are described in details in PIC/S recommendations [4]. Qualification is carried out in three stages, IQ, OQ, and PQ.
Steam dryness, steam superheating, noncondensing gases, and condensate electrical conductivity are the normalized parameters important for the sterilization quality.
TERMS AND DEFINITIONS
Clean Steam means a steam produced in a specialized steam generator from the conditioned drinking water which condensate meets, according to the Pharmacopoeia the quality criteria of "water for injections". Basically, it is used in medicine, electronics and food production.
Steam humidity means the ratio of the dropping liquid contained in a saturated steam to the total quantity of the mixture of phases.
Noncondensing gases mean air and other gases, which are not condensed under the steam sterilization conditions.
Superheated steam means a steam heated to a temperature, exceeding the boiling point at a given pressure.
CLEAN STEAM SYSTEM
The rules of design and assembly of clean steam systems are described in the ISPE Guideline "Baseline Pharmaceutical Engineering Guide for New and Renovated Facilities", volume 4 "Water and Clean Steam Systems" [3].
It is strongly recommended to indicate the bleed clean steam points both for monitoring needs and for steam qualification.
Bleed points are arranged at a steam generator inlet and near each steam consumer. Three main factors can affect the steam quality:
- feed water quality (treatment and cleaning);
- steam generator equipment;
- steam distribution pipelines and valves;
See below the steam bleeding diagrams in accordance with GOST and their implementation by using a KIT ASEPTICA CLEAN STEAM for qualifying the clean steam systems.
Steam dryness
Steam sterilization requires a continuous supply of dry saturated steam.
Excessive humidity, transferred in the aerosol form can lead to overwatering load, whereas too low humidity cannot prevent the steam transformation into the superheating steam when it is expanded in a sterilization chamber. It is hard to accurately measure the moisture content percentage and the traditional methods require a continuous steam jet and cannot be used in sterilizers. The testing method described below should be considered as a demonstration of a good quality of a steam, not as an instrument for measuring a real content of moisture in steam.
Steam superheating
Checking steam for superheating must show that a quantity of moisture transferred with a steam is sufficient (not sufficient) to prevent transformation of a saturated steam to the superheated steam at its expansion in a sterilizer chamber.
Noncondencing gases
Checking a steam quality and the content of noncondensing gases must show that the noncondensing gases content level contained in a steam does not prevent achievement of sterilization conditions in any part of the sterilizer loading. This checking method can be considered as a demonstration of a good quality of a steam, not as an instrument for measuring of a real content of noncondensing gases in a steam.
Electrical conductivity of condensate
When bleeding samples of clean steam, it is necessary to remember the following:
- steam is a dangerous medium which requires strict adherence to safety measures when working with it so as to avoid burns and more grave injuries;
- the materials of devices, valves, fittings, measuring instruments, etc., should not affect the steam quality. They can be: AISI 316 L stainless steel, glass, fluoroplastic, or silicone;
- a steam bleeding kit includes dozens of accessories, so it takes up a large volume and is rather heavy;
- steam sampling procedures are time-consuming. Determination of dryness, overheating and noncondensing gases at one point takes up about six hours.
The kit consists of:
- common components (measuring knee, temperature record device, temperature sensors, a pressure sensor, a pressure gauge, a tripod, silicone hoses, fittings and a case);
- accessories to determine noncondensing gases (a 2 liter capacity container with an overflow system, a funnel with parallel walls, burettes, a needle valve);
- accessories to determine the steam dryness (Pitot tubes – 3 pcs, Pitot tubes spare nozzles, a thermos, scales and silicone plugs);
- accessories to determine superheating steam (Pitot tubes, fittings);
- accessories to determine electrical conductivity of condensate (a heat exchanger, silicone hoses and conductivity meter).
CONCLUSIONS
It is important that throughout the entire process of distribution and supply of steam, it has been produced and maintained in a high quality condition. Therefore, clean steam must comply with strict requirements that depend on the final application.
Engineers of LLC "VALIDATION LABORATORY ASEPTICA" propose:
- ualification kit for the ASEPTICA CLEAN STEAM system;
- ervices in certification / qualification of clean steam systems;
- raining in testing clean steam quality. ■
Declaration of Competing Interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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