Laminar flow work stations

It should be remembered that HEPA-filtered laminar flow work stations designed to provide horizontal or vertical clean air flows are suitable for aseptic purposes only and offer no protection to the worker. Hazardous biotechnology processes must not be carried out in such areas. 

---

A quantity sufficient to carry out the required tests, generally in duplicate, are filled into the containers. Most substances for which there are no concerns for either toxicity or stability are filled by weighing the appropriate quantity into antibiotic vials in a horizontal laminar flow work station. These operations are carried out in a self-contained cubicle to avoid cross-contamination. The vials are then closed with butyl rubber stoppers and sealed with an aluminium crimp seal using an automatic crimping and labelling machine. 

Laminar air-flow work station. Systems should provide homogeneous air speed of 0.3 M/s vertical and 0.45 M/s horizontal flow. 

Grade A The local zone for high risk operations, e.g., filling zone, stopper bowls, open ampoules and vials, making aseptic connections. Normally such conditions are provided by a laminar air flow work station. Laminar air flow systems should provide an homogeneous air speed of 0.45m/s +/-20% (guidance value) at the working position. 

Open circuit operations involving products or components not subsequently sterilized should be carried out within a laminar air flow work station (grade A) in a grade area. 

A Laminar air flow work station 3500 none less than 1 ... 

Riling large volume parenterals should be done under laminar air flow work station, in a Grade C environment The same conditions are recommended for small volume parenterals. 

The number of air changes should geneidly be higher than 20 per hour in a room with good air-flow pattern and appropriate HEPA filters. Source reference 8. Laminar air-flow work station. Systems should provide homogeneous air speed of 0.3 m s vertical and 0.45 m s horizontal flow. 

The greatest risk of contamination of a pharmaceutical product comes from its immediate environment. Additional protection from particulate and microbial contamination is therefore essential in both the filling area of the clean room and in the aseptic unit. This can be provided by a protective work station supplied with a unidirectional flow of filtered sterile air. Such a facility is known as a laminar airflow unit in which the displacement of air is either horizontal (i.e. from back to front) or vertical (i.e. from top to bottom) with a minimum homogenous airflow rate of 0.45 ms" at the working position. Thus, airborne contamination is not added to the work space and any generated by manipulations within that area is swept away by the laminar air currents. 

In the early days of laminar flow, the idea of entire rooms being protected by laminar flow was greeted with enthusiasm. They are now rarely found in connection with aseptic filling. They arc far more expensive to construct than conventional turbulent flow clean rooms, because of the need for more filters and greater engineering capabilities to move a lot of air at high velocity. Moreover, a horizontal laminar flow wall provides unidirectional air flow only as far as the first work station. Thereafter it is no different from a conventional clean... 

This may be achieved by the provision within the work station of a laminar flow of HEPA-filtered air and by fitting air-locks to entry ports. Total containment work stations may provide these requirements. They should be in an environment conforming to at least grade D. 

A.3.5.3 Laminarity of flow 15.A.3.5.3.1 This control checks whether the flow of air at the level of the work stations is laminar and not turbulent, i.e. that the mean velocity in the direction of flow lies within the limits of 10 percent of the theoretical velocity and that each of the values measured does not vary by more than 20 percent from the mean velocity measured. 

The filling of products to be terminally sterilised should be carried out in an appropriate environment for control of viable and non-viable airborne particulate matter. Extra precautions in the form of contained work stations and/or laminar air flow protection may be necessary when solutions intended for intravenous use are filled into wide-necked containers. 

Basic Environmental Standards Aseptic Areas For aseptic processing, rooms with conventional filtered airflows and with contained work stations in the form of filtered air hoods or laminar air flow protection at working points are usually more appropriate than laminar air flow rooms. 

Are Laminar Flow (supplied air) Islands provided at work stations ... 

---