50 Years, 50 Articles

Title Authors Abstract
DISTRIBUTION OF MICROBIAL CONTAMINANTS IN OPERATING THEATRES AND HEALTHCARE ENVIRONMENTS

Hansjörg Rotheudt, Eugen Lichtner, Gerrid Brockmann, Valeria Hofer, Tunc Askan, Anne Hartmann, Benjamin Zielke, Martin Kriegel Contamination control in healthcare facilities against airborne pathogens is a challenging task to prevent nosocomial infections and the distribution of highly infectious diseases from one patient to another. In different areas and contamination protected areas like operating rooms, isolation wards and intensive care units, similar tasks for the ventilation scheme and knowledge about the distribution of pathogens in the airflow is needed. Most investigations and the standard test cases for acceptance tests consider particulate contaminants of small particle size that is completely airborne without gravitational effects. Most microbial contaminants like respiratory droplets and skin flakes have particle diameters of 1 to 20 μm. These particles are also affected by their gravitational settling and do not perfectly follow the airflow motion. The gravitational forces lead to significant increase of their deposition behaviour. Investigations that consider the microbial particulates as completely airborne have limited validity to predict the surface contamination inside the patient’s wound field or on medical instruments and equipment. However, accurate prediction of the behaviour of the contaminants is fundamental for risk assessment and performance tests of ventilation systems. Numerical simulation models to calculate the particle motion and interaction to the airflow field provide more detailed information about the paths for contamination and infectious diseases. To develop and evaluate contamination control strategies for healthcare environments, the method to simulate the movement of pathogen contaminants has major importance. A CFD simulation is a resource-efficient approach. It provides valuable insights into the three-dimensional and transient behaviour of contaminants. Accumulation zones of contaminants in the air and deposition spots on surfaces can be located and the optimal positions of monitoring devices can be found. The state-of-the-art approaches in particle modelling and simulation as well as their advantages and limitations are presented. Within several research projects in the field of cleanrooms, health care facilities and contamination control, the exposure, distribution, deposition and resuspension of airborne particles ranging from 0.1 to 20 µm are investigated at the Hermann-Rietschel-Institut (HRI). In this range of diameter, the transition zone between airborne particles and particles which are highly affected by gravitation is particularly challenging.
Microbial ContaminationParticle DistributionDeposition Of Airborne BacteriaParticle ModellingOperating RoomsAirborneHealthcareContaminationDesignIsothermal
CONTAMINATION CONTROL IN OPERATING THEATRES

Remko J.R. Noor MSc Patient safety is a main topic during surgery. One of the main issues inside operating theatres (OR’s) is the prevention of airborne particles with bacteria that contaminate the wound area and the instruments. The risks and requirements differ for different types of surgery. To minimize the contaminations and improve the patient safety, controlling the quality of the air inside an OR is essential. Several type of air handling systems are available, suitable for different types of surgery. The most used systems are:
• Turbulent Mixed Airflow systems
• Laminar Airflow systems
• Temperature Controlled Airflow systems

The number of colony forming unit is the environment around the patient has an effect on the surgical site infections. When the environment in the OR is clean, the risk of infection will decrease. What is the best ventilation system in an OR in relation to the requirements of surgery, airborne particles and the use of antibiotic prophylaxis? This paper will provide a comparison of different ventilation systems that will support hospital staff to make decisions about the quality of their Operating Theatres. The three systems will be compared both “at rest” and “in operation”.
Performance Of Ventilation Systems In Or’sOperating RoomsAirborneVentilation SystemsContaminationAirflowAt RestIn OperationSurgical Site InfectionsPatient SafetyPoisoning
NEW GUIDELINE ON TESTING OPERATING THEATRES IN THE NETHERLANDS

Frans W. Saurwalt Operating theatres in the Netherlands are commonly based upon the use of Uni Directional Airflow in the middle of the room, in order to protect the patient, operating staff and the instrument tables. From the early days on these UDF systems have been qualified on design parameters and were tested only by air cleanliness classification by particles, at rest. As this is method not totally satisfactory, within the VCCN, a project group evaluated various methods of testing and came to a new approach. The test principle based on segregation test is proposed for adoption in the ISO-14644-3. The method has been tested and improved and is proven to be helpful in assessing operating rooms and instrument lay-up rooms. The ultimate test is the cleanliness during actual surgery. A methodology to monitor is currently under development and practical evaluation is on its way.
Operating TheatresInstrument Lay-up RoomSegregation TestMonitoringOperating RoomsHospitalUnidirectional AirflowVccnRoomTestingTest Method
DETECTION OF MICROORGANISMS IN COMPRESSED GASES

Hans Zingre, R. Meier The International Standard Norm ISO 14698-1/21 demands the monitoring of bio contamination in
compressed gas systems which are used in pharmaceutical production processes. The norm describes the
detection of bio contamination by sampling and enumerating viable units with appropriate methods.
Two main questions were investigated:
Do microorganisms survive in compressed gas systems?
If they survive, what appropriate method has to be applied in order to sample and enumerate them?
13 different medical relevant species of microorganisms where grown and put under pressure from 10 to 170
bars. Their growth and behaviour under pressure and the effect of decompression has been analysed.
Based on the MAS-100 CG Ex (Microbiological Air Sampler for Compressed Gas) this presentation shows
that microorganisms can be measured and what trapdoors are to be avoided when dealing with colony
forming units under pressure
Microorganisms Under PressureCompressed GasesIso 14698Mas-100 Cg ExNitrogenCarbon-dioxideArgonOxygenPharmaceuticalFood Industry
RISK MANAGEMENT FOR A PROFESSIONAL CLEANROOM CLEANING

Frank Duvernell Managing a cleanroom either with microtechnology or microbiology demands needs a professional cleaning
management. How to develop such and how to identify and avoid risks during the insatallation of the
cleaning management is the content of this lecture.
The following lecture is in german language and available also in English.
Cleanroom ManagementRisk ManagementCleanroom CleaningMicrobiologySurfacesContaminationEmployeeClothingRisksPersonel Training
SWEDISH SURVEY AND A SUMMARY OF INVESTIGATIONS IN OPERATING ROOMS

Bengt Ljungqvist, Johan Nordenadler, Berit Reinmüller A survey is presented with data from 27 operating rooms in four county councils, where information from
111 ongoing surgical operations was given regarding air volume flows, measured concentration of airborne
viable particles and used clothing systems. With results from the survey the mathematical expression
describing the dilution principle was established to predict the concentration of airborne viable particles
present in the operating room during ongoing surgery. As well supply air system as surgical clothing system
used play here an important role
Operating RoomsOperating TheatresHospital VentilationBacteria-carrying ParticlesSwedish SurveyAirborneFiltrationClothingSupply AirTurbulent Mixing Air
CLOTHING SYSTEMS USED IN OPERATING ROOMS - A QUESTION OF PATIENT SAFETY

Bengt Ljungqvist, Berit Reinmüller The number of airborne bacteria carrying particles in the operating room is considered an indicator of the risk of infections to the operating patient. Today when the supply air in the operating room is HEPAfiltered, the main source of airbome microorganisms is people (patient and personnel). The filtration efficacy of the fabric in operating clothing system plays an important role. The design of the clothing system also affects the number of particles generated from people to the air of the operating room. In ultraclean operating rooms, the selection of clothing systems for the operating personnel can no longer be thought of in terms of comfort but in terms of patient safety.
Results from clothing systems evaluated in a body-box test chamber and in operating rooms will be presented. The influence of different clothing systems in the operating room with different air volume flows will be discussed.
HospitalOperating RoomPersonnelClothingGarmentBody-boxMicroorganismAirbornePatient SafetyFiltration
ENHANCED BIOSAFETY BSL3+ FACILITY DESIGN & PERFORMANCE QUALIFICATON

Conor Murray This paper deals with biosafety change drivers, biosafety risk assessments, high containment biosafety design, secondary containment barrier design, commissioning & qualification as well as performance & verification testing of enhanced BSL3+ biosafety laboratories which are over and above the minimum requirements of the WHO BSL3 international biosafety standards.
While this paper is not intended to be a complete treatment of biosafety design particular attention is paid to biosafety facility design and construction issues including conflicts between personnel protection (biosafety) vs product protection (cleanroom), the importance of Risk Assessment in choosing the appropriate biosafety level and control measures, the critical linkage between design and a schedule of performance verification tests, common flaws and failures arising during commisioning & qualification and the importance of air leakage measurement in the verification of the Secondary Containment Barrier.
BiosafetyBsl3+Risk AssessmentPersonnel ProductionProduct ProductionLaboratoryBscSecondary Containment BarrierQualificationDesign Principles
VIABLE AND NON VIABLE ENVIROMENTAL MONITORING STRATEGY FOR REAL TIME RELEASE IN PHARMA INDUSTRY

Gilberto Dalmaso The scope of this presentation is to show the usefulness and potentialities of this new rapid microbiological technology/method implemented in the pharmaceutical field in viable and non viable environmental monitoring strategy for real time release in pharma industry and in particular applied on the manufacturing process investigation, using the real-time evaluation, to engage the suitable corrective actions and resolute remedy at the right time. This application has been fundamental to solve an important problem in a short time against the microbiological traditional method resolution, regarding the manufacturing process, which allowed discover and identify considerable benefits. Every day the samples have been analysed in real-time and these results provided a useful mapping of all critical points contaminated to allow the specific actions implementation, reconsider the numbers and type of environmental monitoring and re-samples and which type of sanitization carry out to remove the problem. It is important to underline that the new technology has been able to provide economical benefits in terms of "safe-costs" and the "stock-out" risk reduction of the products as well. Moreover the case study reported has also been useful to implement the process understanding evaluation related to the test carried out in the laboratory until now. This means that in a lot of other fields and other type of analyses this rapid microbiology and the correlated technology could be implemented to improve the quality of the process and the risk of management.
MonitoringMicrobiological TestsRapid Microbiological MethodsAnalytical MethodsReal-timeQbdRmmTimely MeasurementsPatRapid Results
A NEWLY DEVELOPED CLEAN HOOD FOR ISOLATION OF PATIENTS THOUGHT TO HAVE AIRBORNE INFECTIOUS DISEASES

Hidekazu Nishimura, Fumie Kitamura, Soichiro Sakata, Yasushi Kamimura A new medical clean hood was developed for isolation of patients thought to have airborne diseases, such as pandemic influenza and the like. The hood is intended to be used in a ward where many patients are
treated simultaneously in the same closed airspace such as a dialysis facility, in order to prevent cross infection of other patients by the potentially infected patient. The hood consists of foldaway framework, a
fan High Efficiency Particulate Air Filter (HEPA) unit, and transparent polypropylene curtains. The patient is treated inside the hood, and airborne microbes from coughing or sneezing by the patient are contained
inside the hood, and the air containing microbes finally passes through the fan HEPA unit to be released outside the hood as clean air.
Clean HoodIsolationIsolation RoomInfectiousDiseaseAirborne
AIRBORNE BIOLOGICAL CONTAMINATION: MONITORING AND CONTROL

Vance Bergeron Airborne Biological Contamination includes a vast range of particulate and molecular species that present specific challenges for monitoring and control. In particular, the notion of viability places restrictions on
sample collection and analysis. Furthermore, controlling airborne levels of microorganisms requires technologies capable of inactivating and/or chemically eradicating them, as simple capture onto filter media
can lead to proliferation and subsequent release. The advent of new assay capabilities using rapid microbiological methods in combination with effective air sampling techniques holds promise for future
online monitoring systems, while combinations of different technological bricks can be used to tailor air-treatment systems to remove, inactivate and chemically transform particulate, biological, and molecular
airborne contamination.
AirborneContaminationBiological ContaminationMonitoringControl
CLEANING AND DISINFECTION PROGRAM PART OF THE LIFECYCLE APPROACH: A RISK BASED RATHER ARBITRARILY IMPOSED APPROACH

Walid El Azab Is the rotation of more than one disinfectant along with a sporicidal agent mandatory for cGMP compliance? The article will present and analyze the regulatory requirements related to contamination control programs then dive into the requirements for cleaning and disinfection programs, including disinfectant rotation along with a sporicidal agent. the article discusses the process of selection and number of disinfecting agents to be used, the frequency of application, and rotation of (one or more) disinfectants along with a sporicidal agent. Finally, the article reaffirms the importance of periodically reviewing microbial data and auditing practices to confirm the effectiveness of the cleaning and disinfection program including the disinfectant rotation and frequency choice.
CleaningDisinfectionLifecycle ApproachCgmpRisk Based ApproachMicrobiology
INFLUENCE OF EXTERNAL BIOLOGICAL CONTAMINATION ON PARTICULATE BEHAVIOR

Michel Thibaudonab, Julien Clertantc Seasonal Biocontamination is frequently observed both inside cleanrooms and in/on the product. When carrying out sampling of the cleanroom environment, it is necessary to also
sample the outside environment. High levels of pollen and fungal spores outdoors in summer and autumn can correlate to detection of such contaminants inside the clean airlock and
even inside the cleanroom, if appropriate non-cultural methods of detection are used for their detection, whereas classic culture methods are ineffective. Monitoring on a daily or weekly
basis with appropriate method, it is easy to correlate outside levels of pollen and fungal spores with impact inside the installation, and identify the principal mode of transmission as
the personnel, the devices, etc. This enables optimization of gowning and cleanroom cleaning practices to maintain effective control in response to the challenge.
CleanroomContaminationOutdoorIndoorCoriolis
REAL TIME MICROBIAL DETECTION BY LASER INDUCED SPECTROSCOPY AND ITS APPLICATION IN CONTAMINATION CONTROL

J.P.Jiang A technology based on optical spectroscopy has been developed for real time detection of environmental microbes and continuous monitoring of the environment. This technology utilizes
Mie scattering for airborne particle size measurement in the range of bacterial matters, and the detection of intrinsic UV-induced fluorescence from certain bio-chemicals inside bacterial cells
as a biological marker. The optical instrumentation techniques used to achieve the requisite detection sensitivity and the procedure for its validation test will be presented.
One necessary aspect for applying this technology in contamination control is how to correlate its results to compendial microbiological methods and how to set the new limits based on this new
method. A statistical process control (SPC) approach to the environmental monitoring of bioburden in parenteral aseptic facility is proposed to achieve this goal. This presentation will
cover (1) the procedure of setting new limits using a new instrument, (2) the control chart methodology of utilizing environmental monitoring data to assess the state of control in a
parenteral production environment and to troubleshoot the root cause when a variation from normal trend is detected.

Some application examples will be used to illustrate how to utilize the real time microbial detection features of this technology in the environmental monitoring and contamination control.
Topics of discussion include sensor placement, data analysis, graphic data display, and trend analysis.
Real Time Microbial DetectionEnvironmental MonitoringTrend Analysis
ZERO “0” CONTAMINATION CLEANROOMS

Dr, Horst Weissieker, Dipl.- Ing. Hannes Rink From various points of views zero contamination cleanrooms will be necessary in the next 5 years latest. Not only for the coming semiconductor production environments, but also for the nanotechnology and
biotechnology as well as bio-safety new requirements have to be defined. This affects not only cleanroom and clean air but also all other aspects of contamination control from ultrapure media to ultrapure surfaces to the measurements and monitoring of the contaminants and last but not least the control of the contaminations.
CleanroomContaminationZero ContaminationVdi2083-6Iso14644-7
PERFORMANCE REQUIRED FOR AIR SHOWER AND EFFECTIVENESS OF PERFORMANCE

Akihiro Maruyama, Mamoru Okamoto, Toru Kawamata, Han Hyuck Hee Before entering into cleanroom, people will use Air Shower to clean up the body covered by clean garments. Air Shower is expected to protect cleanroom environment from particle and keep the room pressures. Bu it is saying once in a while, that Air Shower is contaminate cleanroom . We evaluated the expected performances and effectiveness of Air Shower, that was installed between test cleanroom and the owning room as simulation.
Air ShowerCleanroomContamination
NITROGEN PURGING OF FRONT-OPENING UNIFIED POD (FOUP) FOR 450MM WAFER MANUFACTURING

Chun-Yong Khoo, Chen-Wei Ku, Shih-Cheng Hu This study aimed to investigate the nitrogen purging of front-opening unified pod (FOUP) with nitrogen for 450 mm wafer which involves stringent cleanliness requirement of water vapor content (RH ≤ 3%)
within the container, besides airborne molecular contamination (AMC). A parametric study was conducted with factors considered to affect the extraction of water vapor content includes the
configuration of plenum injector, purging outlet and FOUP. Computational fluid dynamic (CFD) was employed and Langmuir adsorption models were used to construct physical models of contaminant
concentrations in the FOUP. The results showed that the configuration with nitrogen entering from the rear inlets and the front vent holes and porous ceramics plenum demonstrate favourable water vapor
depletion rate within the gaps formed between the wafers in a fully loaded FOUP. Elaboration of nonlinear fitting was applied to theoretical model and experimental data yields the desorption coefficient
Kd as 0.4 kg/s.
Nitrogen PurgeWaferFoupWafer Manufacturing Airborne Molecular Contamination
A SHORT INTRODUCTION TO CLEANLINESS TECHNOLOGY: MEETING THE FUTURE CHALLENGES

Udo Gommel, Guido Kreck For semiconductor components, the demand to improve performance and velocity as well as energy consumption is met through miniaturization. The continuing trend to miniaturize semiconductor structures can be observed since several decades and requires, among other things, sophisticated cleanliness technology. Cleanliness technology in this context is to be understood as the chain of all activities taken to control and reduce all contamination harmful to the product. Because of the very challenging particulate and outgassing contamination levels, semiconductor industry still claims technological and economic leadership in terms of cleanliness technology. But no longer only semiconductor industry is relying on cleanliness technology as the following case studies graphically demonstrate:
In life science industries, mainly microbiological contamination is controlled to prevent users and patients from severe health issues caused by poor hygiene or cleanliness of the highly effective pharmaceuticals or very innovative medical devices.
Space exploration combines nowadays the challenging cleanliness requirements of semiconductor and pharmaceutical industry to be in compliance with the planetary protection program, the guiding principle to preserve planetary and terrestrial conditions for future generations.
And even automotive industry discovered the benefit of cleanliness technology almost ten years ago: Metallic micro sized particles (>50μm) were identified as critical contamination because they can cause malfunctions in fluidic and electronic vehicle systems such as antiblocking systems.
By having a closer look on these three case studies, the increasing importance and on-going diversification of cleanliness technology can be shown and also the challenging future requirements of cleanliness technology over the next few years can be derived.
Cleanliness TechnologyCleanroom TechnologyContamination ControlMedical DevicesPharmaceuticalsSemiconductorsSpace ExplorationFlight HardwareAutomotive
THE CASCADE APPROACH: SEGREGATION BY AIRFLOW DESIGN N STEAD OF BY ROOM PRESSURE

Ir. Frans W. Saurwalt Governmental inspection bodies as well as internal quality departments have enforced adherence to monitoring of room pressure as a critical aspect. And because of that, the pharmaceutical and medical
devices and healthcare industry puts a strong emphasis on controlling room pressure itself. As clean room construction becomes better and better, resulting in very limited leakage, active room pressure control
becomes more and more complex. With a narrow focus on room pressure control and monitoring, the broader contamination control perspective and a useful different approach is overlooked. Room pressure
control is only one aspect of the concept of segregation of zones of different classes. The broader view has many benefits. This approach is based on designing on airflow in stead of mere room pressure.
While citing ISO 14644-3, and -4 as well as the EU-GMP-vol 4 Annex 1 it can be demonstrated that there is a basis for designing an overflow / pressure cascade. This cascade approach when compared to various other
systems shows to have many benefits; increased protection of the controlled environment, less complexity, better stability, reduced energy-consumption and reduced costs.
SegregationRoom PressureAirflow/pressure CascadeStabilityWind AttackReduced Energy ConsumptionReduced Costs Of Installation
CLEAN BUILD PROTOCOLS- CONCEPTS AND CONSIDERATIONS

Andrew D. Watson A clean build protocol (CBP) is an essential component of a cleanroom
construction project. This paper provides guidance on how to develop and implement a
CBP in order to deliver a cleanroom that can successfully achieve its designated ISO
classification.
Cleanroom ConstructionClean Build Protocols (cbp)
MODERN PTFE MEMBRANE BASED HEPA/ULPA FILTERS FOR IMPROVED ENERGY SAVINGS AND RISK REDUCTION

Marc Schmidt, Ph.D., Sean O'Reilly, Mike Osborne, Ph.D., Jonathan Rajala, Ph.D. Strict demands are put on HEPA/ULPA filters that are installed as terminal filters in cleanrooms, isolators, workbenches etc. or as last filter stage in air handling units being upstream. They must continuously guarantee safe operation while predefined air quality requirements and energy efficiency are optimized. For that the filter media itself is of major importance.

Standard filter media for HEPA/ULPA filters so far had been fiberglass paper. Being free of boron filter media based on expanded Polytetrafluoroethylene (ePTFE) is used in microelectronics since decades. Based on latest developments in membrane technology, such as PAO compatibility, ePTFE and expanded Fluoro-Resin Membrane (eFRM) based HEPA filters are on their way to replace fiberglass-based filters.

This presentation describes how ePTFE and eFRM membrane media contributes to process safety and low-cost operation.

It sets out structure of modern ePTFE and eFRM membrane media, how these air filters provide significant reduction in energy consumption and risk.

It presents results of several studies on superior stability, durability and performance of ePTFE and eFRM media over traditional fiberglass media. Based on several tests regarding mechanical and chemical resistance as well as soot loading it is demonstrated that ePTFE and eFRM media offer a significant improvement in reducing media failure risk for a retained filter integrity.
Eptfe And Efrm Hepa FiltersRisk ReductionEnergy SavingsMechanical And Chemical Resistance