Filter Life Cycle Management

                                   Complete HVAC efficiency highly is dependent on it filters. Good filtration process is the only key to the ultimate objective of a clean room space. When filters are good, then results are best.

                                  This do needs organized procedures and practices inbuilt in the system to achieve the ultimate result. We need to understand the product and its classification of environment, in which it needs to be processed. Ultimate goal is to provide the best class of environment to process the product to produce good quality drugs. The role of product quality gets critical from class D of OSD to Class A of injectables. The more we try to make the environment safe for the drugs, the control measures becomes that more critical too. the filtration process becomes that critical when we go from Class D to C to B to A.

                                                                                                                                             

FILTER LIFE CYCLE MANAGEMENT

  • PROCUREMENT
  • QUALITY CHECK
  • RECEIPT
  • HANDLING
  • STORAGE
  • USAGE
  • LIFE
  • CLEANING
  • SUSTAINABILITY
  • AUTOMATION
  • DISPOSAL

SR NO

STAGES

KEY NOTES

1

PROCUREMENT

•Identify : Determine the type, size, media and efficiency of the filters needed, based on the HVAC application.

•Research Suppliers: Look for reputable suppliers offering high-quality filters that meet your specifications.

•Request Quotes: Obtain quotes from multiple suppliers to compare prices, delivery times, and terms.

•Evaluate Options: Assess the filters based on quality, cost, energy efficiency, and compliance with standards (e.g., GMP, ISO). Note – Filter Media, Media Support, Body MOC, Adhesive Etc to be compared for better selection.

•Place Order: Finalize the purchase with the selected supplier, ensuring clear terms for delivery and payment.

2

QUALITY CHECK & RECEIPT

When receiving HVAC filters, it’s crucial to perform quality checks to ensure they meet specifications and are suitable for use. Here are the key checks to conduct:

•Visual Inspection: Check for physical damage, such as tears, dents, or deformities. Ensure the packaging is intact and free from moisture or contamination.

•Label Verification: Confirm the filter type, size, and efficiency rating (e.g., MERV, HEPA, or ULPA) match the purchase order. Verify compliance with relevant standards (e.g., GMP, ISO).

•Integrity : Ensure a filter integrity test certification (e.g., DOP/PAO test for HEPA filters) to conform there no leaks or defects. Check the uniformity of the filter media.

•Pressure Drop Measurement: Ensure certification for the initial pressure drop to conform it aligns with the manufacturer’s specifications.

•Documentation Review: Verify the supplier’s quality certificates, test reports, and compliance documents. Ensure traceability through batch or serial numbers.

3

HANDLING & STORAGE

Filter handling during transportation and storage are critical. As negligence can damage the filter frame and media, resulting in integrity failure. Storage to be ensured in a area NMT 30 0C so that Media and adhesive properties are not impacted.

4

USAGE

Usage to be done as the scheduled replacement cycle decided in the SOP or as and when required. Necessary documentation to be followed to trace the usage life. If required applicable quality procedure to be followed like Change Procedure or Event.

5

LIFE

Paper Media – Paper Media Prefilters are suggested to replace once in a year.

Synthetic Media – Synthetic Media Pre-Filters are suggested to replace after 30 Cycles of cleaning.

HEPA / ULPA – For Grade A once in Three Years or on to the requirement,

  For Grade B Once in Four Years or on to the requirement,

  For Grade C once in Five Years or on to the requirement,

  For Grade B Once in Seven Years or on to the requirement,

Note – Replacement requirements are subjected to the the Differential Pressure across the filter & the media Integrity

6

CLEANING

Paper Media – Not cleanable

Synthetic Media – Cleanable with Compressed Air or Water

HEPA / ULPA – Not Cleanable

7

AUTOMATION

To have proper traceability of filter replacement and life automation like Barcoding can be done. This barcode scanning data can ensure requirements of audit and compliance and can support during the event investigations also.

8

DISPOSAL

After replacement Filters should be disposed through EHS procedure for the scrap. This will ensure the product traces left in the filter media and their right approach for Human and Environment safety.

HVAC FILTER TYPES

HVAC filters are essential for maintaining air quality and efficiency in heating, ventilation, and air conditioning systems. Here are the common types of HVAC filters:

  1. Fiberglass Filters
  • Description: Thin, flat panels made from layered fiberglass.
  • Purpose: Capture large particles like dust and debris.
  • Pros: Inexpensive.
  • Cons: Limited filtration of smaller particles like allergens.
  1. Pleated Filters
  • Description: Made from polyester or cotton, with pleated surfaces to increase the filtering area.
  • Purpose: Trap finer particles like pollen and pet dander.
  • Pros: Affordable and more effective than fiberglass filters.
  • Cons: Can slightly restrict airflow if heavily pleated.
  1. HEPA Filters (High-Efficiency Particulate Air)
  • Description: Very dense material designed to trap tiny particles.
  • Purpose: Block at least 99.97% of particles as small as 0.3 microns.
  • Pros: Excellent for improving air quality.
  • Cons: Expensive and may require compatible HVAC systems.
  1. Electrostatic Filters
  • Description: Use static electricity to attract and hold particles.
  • Purpose: Capture dust, smoke, and pet dander.
  • Pros: Reusable options available; suitable for households with allergies.
  • Cons: Lower effectiveness compared to HEPA filters.
  1. Carbon Filters
  • Description: Use activated carbon to absorb odors and gases.
  • Purpose: Neutralize smells and VOCs (volatile organic compounds).
  • Pros: Great for odor removal.
  • Cons: Do not filter particles as effectively.
  1. Washable/Reusable Filters
  • Description: Made of durable materials that can be cleaned and reused.
  • Purpose: Trap large particles and reduce waste.
  • Pros: Eco-friendly and cost-saving.
  • Cons: Lower efficiency and require regular maintenance.

CLASSIFICATION WITH RESPECT TO GMP CATEGORISATION

      Maximum Permitted Number of Particles/m3
      At Rest In Operation
GMP
Grade		 ISO 14644-1
Standard Classification		 FED STD 209E Classification
(0.5µ Particles per ft3)		 ≥ 0.5 µm ≥ 5.0 µm ≥ 0.5 µm ≥ 5.0 µm
A 5 100 3 520 20 3 520 20
B 6 1000 3 520 29 352 000 2 900
C 7 10000 352 000 2 900 3 520 000 29 000
D 8 100000 3 520 000 29 000 Not defined Not defined

In the context of Good Manufacturing Practices (GMP), HVAC filters are classified based on their efficiency and application in maintaining cleanroom environments. Here’s a breakdown:

  1. Pre-Filters
  • Purpose: Capture larger particles like dust and fibers to protect downstream filters.
  • Efficiency: Typically G3/G4 or MERV 7-8, with 80–90% efficiency for particles >10 μm.
  • Application: Used as the first line of defense in HVAC systems.
  1. Medium Filters (Bag Filters)
  • Purpose: Remove medium-sized particles (1–10 μm) to improve air quality and protect HEPA filters.
  • Efficiency: M5-M6 or MERV 13-14, with 60–95% efficiency for particles of 1–10 μm.
  • Application: Installed after pre-filters in cleanroom environments.
  1. HEPA Filters (High-Efficiency Particulate Air)
  • Purpose: Critical for filtering submicron particles, bacteria, and microorganisms.
  • Efficiency: H13-H14, with 99.97% efficiency at 0.3 μm for H13 and 99.995% for H14.
  • Application: Essential in sterile and aseptic manufacturing areas.
  1. ULPA Filters (Ultra-Low Penetration Air)
  • Purpose: Remove particles as small as 0.1 μm, including viruses.
  • Efficiency: U15-U17, with 99.9995% to 99.999995% efficiency.
  • Application: Used in ultra-clean environments like aseptic filling zones.
  1. Activated Carbon Filters
  • Purpose: Absorb chemical fumes, gases, and odors.
  • Efficiency: Based on chemical adsorption rather than particle filtration.
  • Application: Used in areas requiring odor and VOC control.

These classifications ensure compliance with GMP standards by maintaining air quality and preventing contamination in pharmaceutical manufacturing.

ISO 14644 CLASSIFICATION FOR MAXIMUM PARTICLE /m3
ISO 14644-1:2015 Cleanroom Standard – This chart details for each classification the maximum number of particles in micrometers (µm) permitted per cubic meter of air.
Class Maximum Particles per m3
≥0.1 μm ≥0.2 μm ≥0.3 μm ≥0.5 μm ≥1 μm ≥5 μm
ISO 1 10 2        
ISO 2 100 24 10 4    
ISO 3 1,000 237 102 35 8  
ISO 4 10,000 2,370 1,020 352 83  
ISO 5 1,00,000 23,700 10,200 3,520 832 29
ISO 6 10,00,000 2,37,000 1,02,000 35,200 83,200 2,930
ISO 7       3,52,000 8,32,000 2,930
ISO 8       35,20,000 8,32,000 29,300
ISO 9       3,52,00,000 83,20,000 2,93,000