Utility Qualification

Facility design is critical. Likewise, individual utilities require qualification. The
most important of these are heating, ventilation, and air conditioning (HVAC),
water (including clean steam), and compressed gases.
Typical programs begin with installation qualification (IQ). The IQ is described
in a written protocol that contains the following key elements:
1. Equipment or system specifications
2. Spare parts list
3. As-built drawings
4. Wiring diagrams
5. Piping and installation
6. Installation certification statement
Following completion of the IQ, the equipment or system is subjected to
operational qualification (OQ). This is a more rigorous exercise in which the
object is to ascertain that the equipment or system being tested performs in
accordance with design specifications throughout the full operational range(s).
The OQ protocol contains
1. A full system description
2. Calibration certification documents
3. Testing plans
4. Acceptance criteria
5. Full record of testing results
6. Certification statement
1. Heating, Ventilation, and Air Conditioning (HVAC)
Features of the HVAC system that affect product quality (sterility) and therefore
require qualification include
1. HEPA filter integrity
2. Airborne particle control
3. Airflow direction
4. Room air pressure differentials
5. Temperature and humidity control
A popular method for certifying the integrity of the filter installation uses
a polydisperse aerosol, created by blowing air through liquid (e.g., poly-alphaolefin)
introduced into the upstream ductwork, followed by scanning the entire
downstream side of the filter face and periphery with a probe nozzle of an
aerosol photometer. This testing will identify “leaks” caused by damage due to mishandling or faulty construction. Small leaks can be repaired with a suitable
silicone-based compound without removing the filter.
The importance of maintaining air pressure differentials in the enclosures
of the aseptic suite within the ranges specified in the design plans cannot be
overemphasized. Reversal of airflow, which can occur if the relative room pressures
are upset, can allow contaminated air from a noncontrolled region into the
clean room, thus defeating the purpose of the HEPA-filtered air supply.
Most enclosures in the aseptic processing suite are not airtight because of
the need for conveyor lines and pass-through openings, so there is a very real
opportunity for contamination from the noncontrolled adjacent manufacturing
areas and particularly from overhead uncontrolled technical areas.
Special monitoring devices known as Magnahelic or Photohelic gauges
measure the pressure differentials across a diaphragm and depict the value in
terms of inches of water or some other convenient scale. These instruments are
very accurate and sensitive to very small changes in pressure differential. Typically
they are connected directly to an alarm system that will cause a visual signal
(flashing light) or an audible signal (alarm buzzer) and/or trigger a recording device
to report a deviation outside a prescribed range of pressure differential.