Transcript GMP Updated Training Modules

Supplementary Training Modules on
Good Manufacturing Practice
Heating,
Ventilation and AirConditioning
(HVAC)
WHO Technical Report Series,
No. 961, 2011. Annex 5
Part 3:
HVAC systems and
components
Section 7
HVAC
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Slide 1 of 28
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HVAC
Objectives
In the following slides, we will study the components of airhandling systems in order to:
HVAC
1.
Become familiar with the components
2.
Know their functions
3.
Become aware of possible problems
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Slide 2 of 28
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HVAC Main subsystems
Exhaust air treatment
Fresh air treatment
(make-up air)
+
Terminal air treatment
at production room level
Production Room
Central air handling unit
HVAC
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Slide 3 of 28
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HVAC
Components
Components in HVAC may include, depending on need:
 Filters
 Fans
– no fan failure; including supply air fans, return air fans,
exhaust air fan, dust extract system fans
 Driers
– Drying of air with chemical driers, e.g. rotating desiccant
wheel
 Frost coils for preheating air
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Slide 4 of 28
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7.1.1 – 7.1.6
HVAC
General
 Pharmaceutical products should be manufactured in areas of
appropriate cleanliness
 Prevent contamination and cross-contamination
 Design of HVAC dependent on various factors e.g.
–
–
–
Outside air quality
Recirculation of air (or not)
Products and range of products
 Risk assessment to determine clean room conditions.
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Slide 5 of 28
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7.1.1
HVAC
General
 Two basic concepts of air delivery
– a re-circulation system, and
– a full fresh air system (100% outside air supply).
 Recirculation – determine the amount of fresh air based
on criteria:
– to compensate for leakage and loss
– to comply with national building regulations; and 7.1.2
– for odour control.
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Slide 6 of 28
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HVAC
General
 Validated automated monitoring systems (e.g. Building
management systems (BMS), building automation system (BAS) or
system control and data acquisition (SCADA) system) - capable of
indicating any out-of-specification condition without delay e.g. by
means of an alarm
– Also helps with preventive maintenance and trend logging
– Critical alarms easily identifiable, visible and/or audible
 Fan interlock failure matrix
7.1.3 – 7.1.6.
 Fan failures can cause a system imbalance, resulting in a pressure
cascade malfunction with a resultant airflow reversal.
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Slide 7 of 28
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HVAC
Air distribution
 Positioning of supply and extract grilles to provide effective room
flushing.
 Low-level return or exhaust air grilles preferred.
 If not possible, a higher air change rate may be needed to achieve
a specified clean area condition, e.g. where ceiling return air grilles
are used.
 There may be alternative locations for return air
7.2.1 – 7.2.2
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Slide 8 of 28
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HVAC
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Slide 9 of 28
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Slide 10 of 28
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HVAC
Air types
Fresh air
(make-up air)
Supply
air
+
Production Room
Return air
(recirculated)
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Slide 11 of 28
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Exhaust
air
HVAC
Recirculation systems
 Increased risk of contamination and cross-contamination.
 Need HEPA filters (EN1822 classification of H13)
 HEPA filters may not be required:
– a single product facility and there is evidence that cross-contamination
would not be possible.
– No dust generated e.g. secondary packing
 HEPA filters installed in the air-handling unit or terminally placed
– If terminally mounted - not with flexible ducting
 If highly toxic processes – never recirculate
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Slide 12 of 28
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7.3.1 – 7.3.6
HVAC
Ventilation with recirculated air + make-up air
Exhaust Unit
Central Air-Handling Unit
Return air
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Slide 13 of 28
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HVAC
Full fresh-air systems
 100% fresh air normally used in a facility dealing with toxic
products or solvents, where recirculation of air with contaminants
should be avoided
 Degree of filtration of the exhaust air depends on the exhaust air
contaminants and local environmental regulations
 HEPA filters in the exhaust system normally when handling
hazardous materials
7.4
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Slide 14 of 28
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Slide 15 of 28
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HVAC
Ventilation with 100% fresh air (no air recirculation)
Washer (optional)
Exhaust Unit
W
Central Air-Handling Unit
Production Rooms
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Slide 16 of 28
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HVAC
Energy-recovery wheels
 Risk assessment to determine cross-contamination risks
 Should not become a source of possible contamination
 Alternatives include crossover plate heat exchangers and watercoil heat exchangers
 Prevent air leakage between the supply air and exhaust air
– exhaust air system operates at a lower pressure than the supply system.
7.4.2 – 7.4.3.
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Slide 17 of 28
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Slide 18 of 28
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Slide 19 of 28
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HVAC
Components
Components in HVAC may include, depending on need:
 frost coils to preheat the air
 reheaters for humidity control, moisture eliminators
 automatic air volume control devices
 sound attenuators
 snow eliminators, dust eliminators,
 fresh air precooling coils
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Slide 20 of 28
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7.5.3
HVAC
Overview components
Exhaust Air Grille
Silencer
Weather louvre
Flow rate controller
Fan
Control damper
+
Humidifier
Prefilter
Cooling coil
with droplet
separator
Secondary Filter
Heating
coil
Recirculated air
HVAC
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Slide 21 of 28
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Filter
Heater
Terminal filter
Production Room
HVAC
Components (1)
 Weather louvre
 To prevent insects, leaves, dirt and rain
from entering
 Silencer
 To reduce noise caused by air
circulation
 Flow rate controller  Automated adjustment of volume of air
(night and day, pressure control)
 Control damper
 Fixed adjustment of volume of air
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Slide 22 of 28
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HVAC
Components (2)
 Heating unit
 Cooling unit/
dehumidifier
 Humidifier
 Filters
 Ducts
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Slide 23 of 28
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 To heat the air to the proper
temperature
 To cool the air to the required
temperature or to remove moisture
from the air
 To bring the air to the proper humidity,
if too low
 To eliminate particles of predetermined
dimensions and/or microorganisms
 To transport the air
HVAC
Air-handling unit
Control damper for airflow
Humid room air
Adsorber wheel
AHU with fan Variable
Speed Controller
Regeneration air
Humid room air
Air heater
De-humidification
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Slide 24 of 28
Dry air
2013
Filter Pressure
Gauges
HVAC
Humidifier
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Slide 25 of 28
Silencer
2013
Heating and
cooling units
HVAC
HEPA or tertiary filter
Primary panel filter
Secondary filter
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Slide 26 of 28
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HVAC
1
2
3
4
Swirl Type air diffusors with
terminal filters
1
2
3
4
HVAC
Filter
Tightening frame
Register outlet
Screw fixation for register
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Slide 27 of 28
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HVAC
Problems with components
 Flow rate controller
 Control damper
 Humidifier
 Cooling battery
 Filters
 Ducts
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Slide 28 of 28
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 Blocked
 Poorly adjusted, bad pressure
differential system
 Bad water/steam quality/
poor drainage
 No elimination of condensed water/
poor drainage
 Incorrect retention rate/damaged/badly
installed
 Inappropriate material/internal insulator
leaking