CAPITULO I Análisis del sector de las frutas y hortalizas
I. 3.1.- Indicadores macroeconómicos
5985 5986
6.3.1 Introduction 5987
5988
The maintenance of systems is vital to achieving proper operation, 5989
appearance, longevity and safety. Inadequate maintenance will 5990
eventually lead to unexpected and extended shutdowns. It will also lead 5991
to underperformance for maintaining the various environmental 5992
(temperature, humidity, air quality, air flow and pressurization) 5993
aspects required for good cGMP facilities.
5994 5995
Predictive Maintenance describes a range of technologies used to detect 5996
developing machinery degradations at an early stage, before they can 5997
become a problem. This allows maintenance personal to order parts, 5998
schedule manpower, and plan multiple repairs during a scheduled 5999
shutdown. The goal of PdM is to proactively correct machinery 6000
degradation before significant deterioration occurs to a critical 6001
component or equipment item.
6002 6003
Traditional Preventative Maintenance (PM) practices cannot identify 6004
mechanical equipment failures that are preceded by detectable changes 6005
in operating temperature, vibration signatures, and bearing wear 6006
indictors. Equipment is susceptible to unplanned catastrophic failure 6007
that interrupts production operations, causes risk to product, and 6008
regulatory inspector the impression of sloppy maintenance practices.
6015
Maintaining clean heating, ventilation and air-conditioning (HVAC) 6016
systems is an important part of sustaining acceptable indoor air 6017
quality (IAQ). Contaminants in HVAC systems can take many forms. Common 6018
contaminants include dust particles (viable and non-viable), active 6019
bacterial or fungal growth, debris from HVAC components (rust, belt 6020
shedding, grease), insulation, mold spores, and other items. For these 6021
reasons good housekeeping practices need to be followed.
6022 6023
Periodic walk downs of mechanical areas to evaluate state of 6024
housekeeping to ensure compliance is maintained at an acceptable level 6025
of quality.
6026 6027
6.3.2 Air Handling Units (AHU) 6028
6029
The unit, which is really a box filled with components to condition and 6030
transfer air should be periodically inspected to identify air leakage, 6031
rusting, condensate drainage, dirt accumulation and for the proper 6032
operation of doors, dampers & actuators, lighting and switches.
6033 6034
Periodic cleaning of the unit‘s interior will be needed especially for 6035
units serving classified spaces and in particular aseptic operation. A 6036
cleanliness inspection should consider all components within the unit 6037
such as filters, heating and cooling coils, condensate pans, condensate 6038
drain lines, humidification systems, acoustic insulation, fans, fan 6039
compartments, dampers, door gaskets and general unit integrity. Though 6040
prefilters are installed, they are not intended to remove all air 6041
particulates. Dirt accumulation can lead to microbial growth. Typically 6042
the units are washed down with a solution that will kill 6043
microorganisms, while at the same time eliminating grease and oil, 6044
which may have been dispersed from bearing and other lubricated joints.
6045 6046
It is recommended to remove visible rust and repaint surfaces to return 6047
their appearance to new.
6048
humid periods when condensate generation is high.
6052 6053
Lighting fixtures where the fluorescent tubes or ballasts have failed 6054
will result in poor lighting levels, which can negatively impact 6055
maintenance on the AHU components and for personnel safety.
6056 6057
Electrical switches and receptacles can lead to electrical hazards, 6058
lower air delivery by the unit, sweating and infiltration of dirt.
6065 6066
All the other components, which are needed to fulfill the role of the 6067
air-handling unit, are discussed below.
6068
Maintaining the desired airflow is critical to providing the
return fans provide semi-conditioned air back to air handling units 6077
6078
Fans have several components, which if not properly maintained will 6079
lead to diminished airflow capacity and eventual failure. They include 6080
the fan housing, wheel, bearings, belts, guards and motor.
6081 6082
The wheel, which generates the airflow, needs to be checked 6083
periodically for accumulation of dirt, mechanical fatigue and 6084
imbalance. These will eventually result in increased vibration and 6085
noise and possible catastrophic failure and a life threatening 6086
condition. If present and not removed, the desired airflow volume may 6087
not be achieved. In addition, dirt accumulation on the fan impeller 6088
will become unbalanced, causing vibration and overloading of the shaft 6089
and motor bearings resulting in catastrophic failure (i.e. broken 6090
blades and housings).
6091 6092
Bearing failure is common due to over or under lubrication and the use 6093
of lubricants, which are not intended for the environment they 6094
encounter. Personnel need to have proper training and services provided 6095
from bearing manufacturers and lubrication vendors are recommended.
6096
Vibration and temperature monitoring can assist in trending analysis to 6097
identify impending bearing failure.
6098 6099
Belt drives need proper care especially as it relates to maintenance.
6100
There are extensive procedures for removing, installing and starting-up 6101
of equipment with belt drives. One item in particular, belt tension, is 6102
one of the most common root causes for premature failure. The following 6103
provides several important steps to follow:
6104
Rotate the belt drive by hand for a few revolutions. Re-check the belt 6110
tension and adjust as necessary.
6111
V-belts will drop after the initial run-in and seating process, failure 6125
to check and re-tension the belt will result in low belt tension, belt 6126
slippage and reduction of airflow. This slippage will result in 6127
premature belt failure.
6128 6129
Motors should be capable of operating for more than 10 years without 6130
major problems. Properly maintained. Since motors are expensive to 6131
purchase and their operating costs are high (e.g. 25hp motor x 8760 6132
hrs/yr. x $0.075/kwh = $12,250/yr.) maintenance is vital to keep these 6133
costs at a minimum and the following few steps should be followed:
6134 6135
External cleaning should be done periodically to remove any contaminant 6136
that would affect heat dissipation from the motor. Wipe, brush, vacuum 6137
or blow accumulated dirt from the frame and air passages of the motor.
6138
Dirty motors run hot when thick dirt insulates the frame and clogged 6139
passages reduce cooling airflow. Heat reduces insulation life and 6140
eventually causes motor failure.
6141 6142
Check for signs of corrosion. Serious corrosion may indicate internal 6143
deterioration and/or a need for external repainting.
6144
dirt and can damage bearings.
6148
cause vibration and noise and possible damage to equipment and person.
6156 6157
6.3.4 Fume Exhaust / Extraction Systems 6158
6159
Exhaust systems serving pharmaceutical operations need to have a high 6160
level of reliability due to the impact on the process should they fail.
6161
Inspect the system to ensure it is free of debris and dirt. If present 6165
and not removed, the desired airflow volume may not be achieved.
6166 6167
Control dampers shall operate freely 6168
6169
Check the flexible duct connections to make sure they are not leaking 6170
air due to deterioration or wear.
6171 6172
Fans are the primary component to the operation of fume exhaust / 6173
extraction systems, refer to the Fan section for details.
6174 6175
6.3.5 Heating & Cooling Coils 6176
6177
Coils, whether for heating, cooling or dehumidifying all have one thing 6178
in common as it relates to their maintenance. They must be clean both 6179
internally and externally and the fins for heat transfer must be intact 6180
and undamaged. Since cooling coils typically have a dual function of 6181
reducing both the sensible (cooling) and latent (de-humidify) heat of 6182
the air, they are more sensitive to reduction in heat transfer than
dirt. Internal cleaning is typically reserved when differential 6188
pressures (inlet vs. outlet) increase beyond what the manufacturer 6189
fluid, which ultimately controls the discharge air temperature. These 6199
valves wear out over time due to the constant modulation to control the 6200
supply quantity of fluid to provide the required discharge 6201
temperatures. These valves should be included in a regularly scheduled 6202
maintenance program.
6203 6204
6.3.6 Humidifiers 6205
capacity for humidification will be reduced.
6215 6216
Inspect the control valve annually to ensure that: (1) the valve closes 6217
off steam tight, (2) the stem packing is not leaking steam, and (3) the 6218
diaphragm in the actuator is not leaking air.
6219
Inspect the silencer at least annually for cleanliness.
6229 6230
6.3.7 Dehumidifiers 6231
6232
Dehumidification of the air supplied to spaces requiring lower humidity 6233
wheel support bearing, fan, fan belts and controls. Maintenance of fans 6238
and belts are discussed in the ―Fans‖ section.
6239 6240
Like any other mechanical equipment, desiccant components must be 6241
maintained according to a recommended schedule.
6242
discomfort due to reduced airflows. Clogged filters on the reactivation 6248
traced to clogged filters.
6255 6256
The drive belt around the desiccant wheel must be tight enough to turn 6257
the wheel, but not so tight as to put an excessive load on the drive 6258
motor shaft bearings. Desiccant units are equipped with automatic 6259
tensioning devices, but belt tension should be checked at least twice a 6260
year, or when the filters are changed, to be certain the belt is 6261
neither too slack nor too tight.
6262 6263
In addition to bearings on the fan section of the unit the desiccant 6264
wheel also has bearings. They should be inspected at the same time that 6265
the fan bearings occur and should be greased based on the operation and 6266
the manufacturers recommendation. Typically greasing is only needed 6267
once a year due to their slow rotational speed.
6268 6269
Controls must have regular recalibration to make sure the system 6270
maintains a steady state of operation.
6271 6272
6.3.8 Air Filtration 6273
with new ones, airflow could be reduced and the filters might collapse.
6277
lower differential pressure set points for change outs. Filters should 6283
be properly installed, so as not to cause air bypassing which can lead 6284
to downstream dirt in the air stream, negating the main purpose of the 6285
filters. Filter manufacturers can provide the optimal scenario for 6286
achieve lowest total cost of ownership based on the operating 6287
conditions at the site.
6288
degradation. Filters should be inspected at a minimum of two times per 6293
year for integrity.
6294
6.3.8.2 HEPA filters are critical to various pharmaceutical operations.
6299
concentration require that the filters be replaced or patched. Testing 6303
is normally performed once a year for most GMP operations, but aseptic 6304
manufacturing requires testing every six months for some areas (See the 6305
appropriate Baseline Guide)..
6306
instruments or hands. Leaks may also occur along the boundary where the 6310
media is attached to the frame by a sealant. The adhesive material can 6311
used in the testing of filters. (See 6.1.8).
6318
replaced when the patchable HEPA filter area is more than an 3% of the 6323
grade applications. (It is not recommended to attempt to use caulk to 6328
repair a leak between silicone gel and the filter frame knife-edge.) 6329
intrusion of foreign matter.
6335 6336
In handling operations, care should be taken to follow manufacturer‘s 6337
recommendations and prevent damage from:
6338
Excessive movement 6342
Rough handling 6343
Improper storage or stack height 6344
6345
Prior to installation it is recommended that information on individual 6346
filters and filter housings be recorded (model number, serial number, 6347
performance, factory test data, etc.). This can resolve future 6348
questions as to filter efficiency, replacement filters or issues 6349
arising from a product recall.
6350 6351
6.3.9 Ductwork 6352
6353
Periodic inspections of HVAC ductwork can identify potential problems 6354
condensation getting into work areas, rusting and mold growth.
6362 6363
6.3.10 Dampers & Louvers 6364
applications, which typically have gaskets, will need to be replaced if 6369
they have become hardened or do not provide a good seal. If these units 6370
are allowed to accumulate dirt or don‘t operate properly will result in 6371
insufficient air distribution.
6372 6373
6.3.11 Diffusers And Registers 6374
insufficient air distribution.
6380 6381
6.3.12 Ultraviolet (UV) Lights 6382
6383
The only significant maintenance required for ultra-violet lighting 6384
used as a germicide is the replacement of the UV lamp or bulb. The 6385
bulbs typically last about 8,000 hours. Their life will be shortened 6386
when dirt has accumulated on them. Dirt acts as a barrier for the lamp 6387
to emit sufficient intensity to effectively destroy microbes. UV 6388
lighting using ballasts will have a long life of typically more than 5 6389
years.
6390 6391
6.3.13 Building 6392
6393
As buildings age, the architectural (ceiling, walls, doors, ceiling 6394
fixtures), mechanical and electrical (piping, ductwork, conduit, 6395
receptacles) components, which penetrate the conditioned perimeter, 6396
requiring adjustments to maintain compliance.
6401 6402
6.3.14 Air Balancing 6403
6404
Testing, Adjusting and Balancing (TAB) for HVAC systems should be 6405
performed within a specific frequency to ensure sufficient current 6406
documentation is available for regulatory agencies to demonstrate 6407
system compliance as well as verify general operation of other less 6408
critical systems are operating as energy efficient as possible. When 6409
changes to the space or HVAC equipment occurs, TAB shall occur at that 6410
time. At a minimum recalibration of instruments, air changes per hour 6411
(ACPH) and differential pressure (DP) shall occur at least annually for 6412
GMP spaces and full rebalancing should be evaluated to be performed at 6413
least every 5 years and 7 years for non-GMP spaces. A total rebalancing 6414
can uncover unsuspected increases in energy consumption and potential 6415
equipment failures.
6416 6417
Room Type Frequency
Aseptic Operation (Grades 5-7) - Re-calibration of Instruments, ACPH & differential pressure; test HEPA filters
6 month GMP Classified Operation (Grade 8) - Re-calibration
of Instruments, ACPH & differential pressure, test HEPA filters
1 year All GMP Spaces, Pilot Plants, Animal Facilities,
Laboratory Space, R&D Space - full rebalancing 5 years Non-GMP Spaces including electrical & mechanical
rooms, auditoriums, utility spaces, central plant ventilation, kitchens and offices - full rebalancing
7 years
6418
Table 6-4 Suggested maintenance frequency 6419
6420