Monitoring Considerations for
Existing facility considerations
Automation Inc. Facilities grappling with USP 797 and USP 800 ver- ify their compliance through cleanroom certifica- tion. Airflow measurements, leakage testing, and environment measurements (differential pressure,
temperature, and relative humidity) are documented
and certified. Non-cGMP certified facilities do not
generally have ongoing monitoring of their cleanroom
space and have difficulties identifying when interven-
tion is required. The challenge for facility managers is
how to monitor their day-to-day operations without
disrupting the facility or adding significant cost.
Existing cleanrooms have numerous non-invasive
options to supplement their facility with monitoring
products. New construction will find “combined”
control systems for FFU operation/optimization con-
taining environment monitoring to be cost-effective
and convenient solutions to monitoring their facility
and optimizing air-management.
Existing cleanrooms complying with USP 797 or USP
800 were generally not designed with centralized
cleanroom monitoring. Small cleanrooms also didn’t
invest in smart FFU centralized air flow controls.
Air-exchanges (ISO 7 or ISO 8 levels) or exhaust (for
negative pressure as specified for USP 800 hazardous
material compounding) are manually adjusted by the
installer/certifier to meet compliance.
Without airflow monitoring the easiest way to
monitor cleanroom airflow changes/stability is by
monitoring the differential pressure maintained
between the controlled environments and their surrounding space (a failed or compromised FFU will
materially impact the differential pressure in a small
cleanroom). Significant changes in differential pressure can point to filter blockages and/or FFU failures.
Most cleanrooms follow a simple floor-plan lay-
out with com-
are available to
assist in the process: monitor the key parameters — dif-
ferential pressure, temperature, RH; notify and alarm
if these parameters change significantly; capture the
data for reporting purposes (data log).
Simplest solutions are stand-alone sensors that
can be mounted inside the cleanrooms that display
their value so the cleanroom staff can manually
check the values, determine if the values have changes significantly (manual notification), and jot them
in a log for future reference (data log).
Moving to more automated processes, sensor
manufacturers provide solutions that have connectivity (i.e., BACNET or wireless) that allow
the sensor data to be transmitted to a central PC
for processing and documentation. Notification
of parameter swings (alarm/notification) can be
accommodated by some sensors and/or left to the
PC consolidation to address. Centralized kits provide
sensors and also fulfill the functions of monitoring,
alarming, and notification.
Facility managers can easily find non-invasive
solutions that allow real-time monitoring solutions to
supplement compliance between certifier visits. From
low-cost sensors that require manual daily activity to
centralized monitoring systems, facility managers can
find cost-effective options. Finding the right mix of
sensor data, auto-alarming and/or notification, and
documentation are the key determinants at different
price points as all solutions can provide adequate support to supplement day-to-day monitoring.
New USP 797 and USP 800 construction have
the benefit of installing cost-effective non-cGMP
monitoring systems for their cleanroom space.
Additionally, network-capable FFU units provide
for centralized monitoring and control of air-flow
and cleanroom stability. When monitoring the FFU
performance and differential pressure between
rooms, the FFU units can be set to optimize the
air-exchange demand and the differential pressure
requirements. The positive pressure requirement
for non-hazardous compounding and negative differential pressure required by hazardous material
processing relies on air-flow adjustments that can
be efficiently addressed through FFU centralized
controls. As USP guidelines consider adjustments to
air-exchange requirements for compliance, systems
can be easily adjusted to match the changing land-
STANDARDS AND PROCEDURES
Typical 3-room USP 800
or USP 797
compliant floor plan.
Image: Courtesy of Terra