Laminar flow room

Measure the average face velocity of each terminal HEPA filter. Measure the average velocity 1 ft above the workspace, exposed product areas, or exposed component areas in all Class 100 laminar flow rooms or areas. 

The average face velocity of terminal HEPA filters servicing Class 100 laminar flow rooms is 90 ft/min 20%, with no points below 75 ft/min or above 105 ft/min. 

Where product is exposed at transitions or packing operations use containment devices such as gloveboxes provide airflow control (laminar flow booths) or as a last resort use the room as containment and provide suitable personal protective equipment for the operators... 

The arrangement shown in Fig. 9.28 is used in industrial halls or auditoriums. Clean rooms have complex systems using laminar flow to ensure that the room IS fully ventilated. 

Figure 9.29 shows a typical arrangement of a laminar-flow clean room. The flow may be vertical through a perforated ceiling and floor. 

Vertical laminar flow clean benches also are not BSCs. They may be useful, for example, in hospital pharmacies when a clean area is needed. Although these units generally have a sash, the air is usually discharged into the room under the sash, resulting in the same potential problems as the horizontal laminar flow clean benches. 

All laboratory operations are carried out in laminar flow cabinets in rooms in which filtered air is maintained at a slight positive pressure relative to their outer environment. Operators wear sterilized clothing and work aseptically. Antibiotic fermentations are, of strict necessity, pure culture aseptic processes, without con-tamirrating orgarrisms. 

Filtered air may be used to purge a complete room, or it m be confined to a specific area and incorporate the principle of laminar flow, which permits operations to be carried out in a gentle current of sterile air. The direction of the airflow may be horizontal or vertical, depending upon the type of equipment being nsed, the type of operation and the material being handled. It is important that there is no obstruction between the air supply and the exposed product, since this may resnlt in the deflection of microorganisms or particulate matter fiom a non-sterile surface and canse contamination. Airflow gauges are essential to monitor that the correct flow rate is obtained in laminar flow units and in complete suites to ensure that a positive pressure fiom clean to less clean areas is always maintained. 

Carolina in 1981. Each sample (1.4 ml of methanolic sample) was placed into a 3-cm petri dish and the solvent evaporated under a laminar flow hood at room temperature. Seventy seeds (0.035 g) were then placed into the petri dishes and 1.4 ml of sterilized (0.2 pm-filter) 15 mM Mes [2-(N-morpholino)ethanesulfonic acid Sigma Chemical Co.] buffer adjusted to pH 5.5 was added. The dishes were kept in the dark at 25°C2for 84 hr, exposed to 12-hr fluorescent light (250 p einsteins/m /sec), and then placed back in the dark for an additional 4 days (17). Percent germination, root and hypocotyl lengths were then determined. 

A laminar flow enclosure provides a means for environmental control of a confined area for aseptic use. Laminar flow units utilize HEPA filters, with the uniform movement of air along parallel lines. The air movement may be in a horizontal or vertical direction and may involve a confined area, such as a workbench, or an entire room. Laminar flow modules are suspended above filling lines, vial- and stopper-washing equipment, and other processes to provide an aseptic and particulate-free environment. 

Regardless of the methods used to obtain a clean air environment, unless the parenteral operator is made completely aware of the limits of laminar flow, uses careful, planned movements, and is wearing proper clothing, he or she can be a source of product contamination. Operator movement within aseptic rooms should be minimized. The rooms must be disinfected regularly and thoroughly before setting up for aseptic operation. 

The equipment needed is determined by the type and extent of the services chosen to provide. Hospitals already utilize laminar flow hoods for aseptic compounding of sterile solutions. The same hoods can be used to compound other sterile products such as eye drops. A balance, preferably electronic, is essential. Ointment slabs (pill tiles), along with spatulas of different types and materials, should be on hand. A few mortars and pestles (both of glass, ceramic, and/or plastic) should be obtained and some glassware. It may not be necessary to buy a roomful of equipment, but one should purchase what is needed to start the service, and build it up as the service grows and expands to different arenas. 

Figure 3.1. Diagrammatic illustration of the flow pattern of HEPA-filtered air through a t5 pical clean room. Air is pumped into the room through HEPA filters (see text) located in the ceiling, and exits via extract units, normally located at floor level. Although the air flow is non-unidirectional (i.e. not true laminar flow), it generates a constant downward sweeping motion, which helps remove air-borne particulate matter from the room...

Downstream processing is normally undertaken under clean room conditions, with the final steps (e.g. sterile filtration and aseptic filling into final product containers) being undertaken under Grade A laminar flow conditions (Figure 3.18). 

Glass vials are received from the warehouse and enter the washing area. The vials are washed in a validated vial washer, using deionized water and water for injection with sterile compressed air. The vials are depyrogenated in a validated laminar flow dry heat tunnel and unloaded into the sterile filling room under laminar flow. 

The dry heat tunnel is connected directly after the washing machine. Starting at this point, the vials will be processed under class 100 laminar flow areas. First, the washed vials are loaded directly to the preheating zone of the tunnel, which is covered by HEPA filtered laminar flow. The vials are heated and dried properly before passing to the second stage, sterilization and depyrogenation zones. Finally, the vials will be cooled down to room temperature at the cooling zone. 

All finished products are tested for sterility in a controlled-access clean room environment in a laminar flow hood, which provides no greater level of a microbial challenge than that encountered in the fill environment. The testing environment consists of a gowning room and sterility test suite that meets the same air quality standards as the hlling suite. 

C.O.R = centre of the room. LFH = under laminar flow hood. LAF Laminar flow... 

Intuitively, GSD can be considered to be inversely related to the efficacy of installed engineering controls. A GSD of 1.0 means that all exposures are identical, a condition nearly realized in some laminar flow clean rooms. When GSD > 2.5, as may be the case for some kinds of maintenance work, it is likely that there are no functioning engineering controls. The exposure variability for most American workers is characterized by a GSD lying between 1.2 and 2.5 (3). 

Take 10 eggs (5-7 days old make sure that they are kept at the same temperature until the start of the procedure), wash with 70% ethanol and open at the egg s pole under sterile conditions in laminar flow. Decapitate the embryo, isolate the heart from the embryo and remove the atria. Bath the ventricles in 5-10 ml HBSS at room temperature in a Petri dish. 

Because of the sensitivity of PCR assays, it is most important to minimise the potential danger of cross-contamination. Ideally, PCR laboratories should consist of two separate rooms, each containing their own equipment (e.g., pipetors). One room should be dedicated to the setting up of RT reactions and PCR assays only. Both laboratories should use aerosol-resistant tips to prevent carry-over of sample within the barrel of the pipet. Post-PCR tubes should never be opened in the room used to set up PCRs as this is probably the most potent source for potential contamination. A laminar-flow cabinet, particularly one designed for PCR, should be considered a requirement for a PCR room in situations where a large number of samples will be processed. 

Exchange of old gas only (linear, laminar flow along the entire cross-section of the room) air exchange time roughly identical with ventilation time Technically not given in the facilities under consideration. 

A complete visual representation of the manufacturing process in flow chart format should be included. This flow chart should indicate the step in the process, the equipment and materials used, and the room where the operation is performed, and should provide a complete list of the in-process controls and tests performed on the product at each step. The diagram should also include information, including a descriptive narrative, on the methods used to transfer the product between steps (i.e., sterile, SIP connection, sanitary connection, open transfers under laminar flow units, etc.). 

Experimental data were obtained for water flows at room temperature. PoiseuiUe number is plotted versus the Reynolds number in figure 17. It can be observed that a classical value for a laminar flow is found, as expected. The slight underestimation observed is probably due to the experimental imprecision on the estimation of the channel height... 

On a broader scale, pharmaceutical manufacturers were beginning to utilize absolute filtration as a primary engineering control in the maintenance of large, carefully controlled clean spaces in the batch production of quality-controlled parenteral products. In this application, LAF was supplied directly to production lines and extended critical worksurfaces within defined, non-turbulent entrance and exit planes as parallel or columnated airflow (misnamed laminar flow ). This highly controlled laminar airstream was supplied to the critical worksurface, in addition to conventionally supplied turbulent airflow to the general space, provided through terminal diffusers for filtration of the balance of room air. In this manner, the stepped control of all critical, as well as support areas was achieved. 

---