| Laminar flow creates an aseptic, non-turbulent work | | | | - Directing airflow in the room of a patient who must |
| environment for a variety of applications. This | | | | not come in contact with contaminants. An example |
| technique for airflow particulate cleanliness has been | | | | is the burn patient, with large exposed areas of flesh. |
| in wide use to protect animal and human beings, | | | | - Controlling airflow in the room of a patient who is |
| processes, and products since the 1970s. In 2000 the | | | | extremely contagious, so that the contaminants he |
| International Standards Organization published | | | | emits will not enter the environment of unprotected |
| performance standards. The term originates from the | | | | individuals. |
| word laminae, the plural of lamina, referencing the | | | | - Biological laboratories in which contagious bacterial or |
| layers of air that flow over one another to guarantee | | | | viral germs must remain contained. |
| clean layers of air. | | | | - Pharmacological facilities in which environmental |
| It is easy to illustrate both the necessity and the | | | | control permits successful compounding of sterile |
| principle of air particulate cleansing if you look at a | | | | medications or solutions-think chemotherapy-or in |
| window when it's opened. Sunlight falls on tiny dust | | | | intravenous solution preparation. |
| motes traveling through the room's air. Now suppose | | | | - Biological testing laboratories, when the integrity of |
| that someone with a viral infection has just sneezed | | | | animal or plant specimens must be guaranteed. |
| into the room, and the spray that he exhales | | | | - Robotic equipment, whether utilized in the |
| contains hundreds of thousands of viruses. What if | | | | preparation of medical admixtures, high throughput |
| each one of them attaches itself to a dust particle? | | | | testing, or industrial small part assembly. |
| Laminar flow hoods remedy that dilemma, and they | | | | - Scientific applications, in which the quality of air |
| have many additional applications. But first consider | | | | emissions must be guaranteed during quality control |
| how they work. There are two basic designs: vertical | | | | processes for small computer system interfaces or |
| or horizontal hoods. | | | | other instances of equipment sensitivity. |
| Vertical hoods channel the room's air through an | | | | - Industrial uses, including the use of laminar flow to |
| intake. A blower directs it toward a HEPA (high | | | | eliminate sound and air vibrations disruptive to |
| efficiency particulate air filter). Some of the air is | | | | sensitive equipment. |
| eliminated via an exhaust vent and leaves the area | | | | - Electronic testing, inspection, and manufacturing. |
| entirely. Once the air is filtered through the HEPA, it | | | | - Food industry, for aseptic food preparation. |
| flows back into the room. The air flows constantly | | | | Add-on equipment depends on the application. In |
| through the room, in layers. Suppose we are in the | | | | most laboratories you will find use for ultraviolet |
| hospital room of a patient, and a hospital technician | | | | lights, butterfly valves, fume hoods, plus more. Some |
| enters the area. The laminar flow hood will draw | | | | equipment is designed to provide an unimpeded view |
| contaminants off the technician and immediately cycle | | | | while working with acrylic sidewalls or back panels. |
| them through the HEPA. | | | | You will most likely need exhaust blowers, low flow |
| Horizontal hoods are typically designed as work | | | | alarms, and exhaust transitions. |
| benches. Below the work surface you will find a | | | | The specific application affects the design of the |
| pre-filter that draws the room's air up to the HEPA. | | | | hood or work bench and dictates which features are |
| From the HEPA the air is cycled smoothly over the | | | | necessary. Costs are high, but laminar flow hoods |
| work surface. | | | | eliminate catastrophic costs associated with |
| General applications for laminar flow include medical, | | | | contamination. Most companies will provide you a |
| scientific, pharmacologic, robotic, industrial, and | | | | quotation based on your specific needs. |
| aerodynamic applications, such as: | | | | |