1. Laminar Flow
Purpose
Laminar flow in a bench used in microbiological inoculation. It keeps sterile atmosphere to
carry out microbiological inoculations.
Conditions & Requirements: The bench shall be compatible with the climatic and other
environmental conditions of Indian laboratories
Specifications:
Description • Horizontal laminar flow conforming to class 100
conditions of the U.S. Federal Standards 290 B
Work area • Bench of 120 cm X 60 cm X 60 cm, with white
sunmica top
Principle • Double filtration of air and provision for UV light to
make work area microbe free
Filters • Filters with at least 98% efficiency for particles of 0.3
µM or larger size
Housing • Wood or melamine or equivalent
• Blower: 220 VAC ±10%, 47 to 53 Hz
• UV Lamp and other fluoroscent light: 220 VAC ±10%,
47 to 53 Hz with certification
• Provision for a UV tube light and a fluorescent tube
light
• Tested for leaks and certified
• Blower: Dynamically balanced, and with at least 0.25
Horse Power electric motor operating on 220 VAC
±10%, 47 to 53 Hz AC power supply
• Static pressure manometer to measure the air flow rate
Method • To avoid contamination during microbial inoculation,
filtered air is blown on work bench from opposite side
to make the working environment microbe free.
• The filtration of air is performed through filters having
pore size < 0.3 µM
Operation and Performance • The filtration of air is performed through filters having

2. • Pore size < 0.3 µM
• Air flow: 3 m3
per minute
• Noise: Less than 65 db at work area
• Vibration free work table
• Light level: More than 100 feet candle in work area
• Filtration with 98% removal of suspended particles of
0.3 µM size or bigger
• Installation qualification, operational qualification and
performance qualification certificate from NABL
Accredited Laboratory or US-EPA certificate of
performance
Accessories • Spare UV tube light
• Static pressure inclined manometer