FAQ


How often am I supposed to get my clean room validated?

ISO 14644-2 specifies that a cleanroom that is ISO class 5 or cleaner needs to have their testing procedures done every 6 months. For any cleanrooms less stringent (class 6 through 9) it is only necessary once per year.

Is cleanroom monitoring and cleanroom certification the same thing?

No. Cleanroom certification involves checking the room for various parameters to ensure that it has been built according to the proper requirements set out in ISO 14644. The room is also routinely retested to confirm continued success of the original standards the building was built to achieve.

On the other hand, cleanroom monitoring applies a broader approach – helping to show trends in particles and airflow in day-to-day processes. Continued monitoring can help pinpoint potential issues that are starting to occur or are getting worse – allowing the management to fix the protocol, filter or equipment issues that would affect future certification results and or product yield.

What is involved in cleanroom certification?

Cleanroom certification involves checking the cleanroom for specific parameters to ensure that it is built to the proper set of requirements. The room is also routinely retested to the same factors to ensure the quality has not changed during operations conducted in the cleanroom space.

When a cleanroom is certified to a specific class, it must operate according to standards that meet or exceed the ISO parameters of that class under a specific occupancy status.

How can I avoid particle dropout?


The rule of thumb for this is “the shorter the sampling tube, the more accurate the reading”.  Ideally, if you’re using .1 CFM, don’t allow the sampling tube to be longer than 2 feet.  With 1 CFM, you can go up to 10 feet, but it is better to keep it between 3-4 feet.

How can I collect particles in one area and count them in another area?


With real-time particle monitoring, a single particle counter or sensor is used at a specified location. Each event is detected and counted, and there are no gaps in the particle counting data. And particles are monitored in particles per cubic foot or per cubic meter. This system is best suited at very critical or sensitive operations, where events can occur suddenly or without warning.

There are several kinds of particle counters available. One type is a stand-alone portable particle counter that comes equipped with a display and built-in carbon vane vacuum pump. The remote counter, on the other hand, has no display and should be connected to a computer, a facility monitoring system or data acquisition system. Vacuum for sampling with the remote counters are furnished via a separate centralized carbon vane vacuum pump that serves several, or all, particle monitor sensors.
Whether a single particle counter or sensor or several sensors are used, real-time monitoring offers a number of important benefits. For example, it provides for the continuous detection of all particle events and emergency reaction to those events. It is also ideal for crucial monitoring, as well as watching equipment for failure and preventive maintenance. Real-time particle monitoring allows for immediate notification or alarming of yield-destroying particle levels, feedback to staff when procedures are not being followed, and feedback after shut down/evacuation procedures to determine if the area is in specification.

How many air changes per hour should my cleanroom have?

Airflow is usually specified either as average air velocity within the room or as air changes per hour.  HEPA & ULPA filters used in most stringent cleanrooms are generally built in ceiling and can be installed in groups housed in a proprietary modular pressure plenum system. They can also be installed in single filter housings, individually ducted, suspended in an inverted “T” grid support system, and sealed to prevent unfiltered bypass air from entering the cleanroom. Cleanroom design conventionally follows the following guidelines for filter coverage:

How many filters should I install in my cleanroom?

HEPA & ULPA filters used in most stringent cleanrooms are generally built in ceiling and can be installed in groups housed in a proprietary modular pressure plenum system. They can also be installed in single filter housings, individually ducted, suspended in an inverted “T” grid support system, and sealed to prevent unfiltered bypass air from entering the cleanroom.  Cleanroom design conventionally follows the following guidelines for filter coverage.