Whatman™ Polyvent (0.2µm PTFE)-Product Information sheet


For research use only.

Not recommended or intended for diagnosis of disease in humans or animals.

Do not use internally or externally in humans or animals.

The Polyvent family of integral vent filters provides a range of dedicated products for the venting of vessels. This family of filter products is constructed from a single standardized set of materials (polypropylene & PTFE), thus simplifying the task of approving materials. From Polyvent 4 to Polyvent 1000, the same materials for the housing and for the membrane are used throughout. By qualifying any one of the Polyvent products, the materials of the full family of Polyvent are tested.

The five Polyvent family members have been designed to provide the optimum sterilizing grade of hydrophobic vents ever manufactured. Venting is the reason for Polyvent, it is not an afterthought.

Typical Applications for Polyvent
Filling Vessels Incubators
Mixing Vessels Autoclaves
Holding Vessels Lyophilizers
Autoclave Vessels EtO Sterilizers
Fermentation Vessels Fermentors
Shipping Vessels  
Dispensing Vessels  

1Sterile Venting
2Gases Pass, Liquids/Aerosols are Stopped

Especially Useful For

Biotech: Sterile vents & exhausts for growth environments.

Pharmaceutical & Diagnostics: Vents for liquid vessels.

Food & Beverage: Vents for holding, shipping and dispensing vessels.

Bulk tanks may store food products, biological products, or deionized water. Vent filters on these tanks allow only sterile, microfiltered air to replace the liquid drawn off for use. Positive pressure may develop in some vessels as sterile gases are pumped into the vessel. Reaction gases must be safely vented off, without contaminating either the environment or the tank’s contents.

A properly designed sterile vent filter allows pressure within a sealed vessel to equalize with external atmospheric pressure. In some applications, protection of the environment from contaminants in the vessel is the objective; in other applications, the objective is to protect the contents of the vessel from external contamination.

  • Integral
  • Bi-Directional
  • Sterile Vent Filters
  • Pure Virgin Polypropylene Structure
  • Broad Family of Devices Specifically for Venting
  • Hydrophobic PTFE Membrane
  • Autoclavable
  • Identification and Lot Number (for GMP’s) Permanently Bonded on each vent*

*Polyvent 4, due to size, does not have Lot or Serial No. on each vent

The Polyvent Family of Vent Filters

The Polyvent Family of Vent Filters


Operating Instructions: Venting

Safety: Considering the special factors of your application, consult the table of Technical Data to determine the correctness of use. Key safety concern is to not exceed the pressure, temperature, or chemical compatibility recommendations.

PTFE membrane considerations: PTFE membrane is hydrophobic and will not allow water (aqueous solutions) to pass without high pressures. These pressures are called the Water Breakthrough Test (WBT) values and change with the pore size of the membrane.

Autoclavability: At 121°C (132°C Max.) for 20 minutes. Multiple autoclave cycles may be possible, however, reuse is the responsibility of the operator, who should protect the device from cross contamination and detect loss of integrity by appropriate testing.

Filtration Installations:

Vents: If exhaust gas is saturated with moisture, install vent filter in a vertical position to allow collected moisture to drain back into vessel rather than fill (and block) vent filter housing. Polyvents are Sterilizing vents, and therefore use a 0.2 μm membrane.

Integrity Testing:

Water Breakthrough Pressure (WBT): The PTFE membrane is hydrophobic. This feature allows a simple yet practical test to be conducted with water to determine gross integrity of the filter device. This procedure is particularly helpful in testing “in situ” devices when used as vents. Use sterile water to fill outlet side of filter. The atmosphere outlet connector is indicated by the labeled side or the flow arrow. Apply 5.0 psi (0.3 bar) controlled pressure for 15 seconds. An integral membrane should hold water. This test is not designed to be definitive for pore size. A WBT cannot be performed following use of alcohol.

Technical Data: Polyvent Filters for Sterile Venting

The Polyvent family of vent filter devices are designed and built with PTFE membrane and polypropylene housing. This compact design provides high effective filtration area in small size.

Polyvent’s light weight is extremely important. When heavy filters are used, they can cause collapsed tubing, stopping the intake of air).Manufactured in GMP controlled Clean Room facilities.


Catalog Number PTFE Product Membrane Housing Connections1 Qty/Pk
WHA67130425 Polyvent 4 0.2 μm 25 mm disc ML/FLL 1/8”/3 mm ID Tube 50
WHA67131650 Polyvent 16 0.2 μm 50 mm disc SB 6 to 10 mm 1/4 to 3/8” 10
WHA67131651 Polyvent 16 0.2 μm 50 mm disc SB 6 to 10 mm 1/4 to 3/8” 100
WHA67135036 Polyvent 500 0.2 μm Capsule 36 (Vented) SB 6 to 10 mm 1/4 to 3/8” 1
WHA2103 Sterivent 36 0.2 μm Capsule 36 (Vented) SB 10 to 13 mm 3/8 to 1/2” 1
WHA67131075 Polyvent 1000 0.2 μm Capsule 75 (Vented) SB 10 to 13 mm 3/8 to 1/2” 1
WHA2107 Sterivent 150 0.2 μm Capsule 150 (Vented) SB 10 to 13 mm 3/8 to 1/2” 1
WHA2108 Sterivent 150 0.2 μm Capsule 150 (Vented) 11/2” Sanitary 1


Maximum Pressure: 2 bar (29 psi)
Housing: Polypropylene
Filter Media: PTFE 0.2 μm
Flow Direction: Bi-directional.
Connectors: For 3 mm to 13 mm (1/8 to 1/2 inches) ID tubing – See specific product.  
Autoclavability: Autoclave at 121°C (132°C Max) for 20 minutes. Multiple autoclave cycles are possible, however reuse is the responsibility of the operator, who should protect the device from cross contamination and detect loss of integrity by appropriate testing.
Integrity Testable: WBT, Water    Breakthrough –Test from outlet side only (Atmosphere connection is indicated by the label or the flow arrow.) – See instructions.


Typical Air Flow RatesI

Typical Air Flow RatesI

Polyvent Filters Retention and Hydrophobicity

Particle retention of membrane filters in air streams is more efficient than in liquid streams by a factor of 10 or more. (2, 6) Retention of particles in liquids is principally by mechanical entrapment while retention in air is by interception, inertial impaction, diffusion, gravitational setting, and electrostatic attraction. (5)

Polyvent Filters (PTFE Membranes) are Rated 0.2 m, in Liquid

Retention of aqueous solutions with particulates by hydrophobic microporous membranes is a function of their WBT value, rather than the pore size. (4)

Liquid water presented to the surface of a hydrophobic membrane at a pressure lower than the WBT pressure will be blocked by the membrane. Water in its vapor form may pass through a hydrophobic membrane as single molecules, which may condense again to form a liquid on the downstream side.

However, it has been reported that no viable organisms have been found  on the downstream side of hydrophobic membranes presented with a biological challenge at pressures below the WBT pressure (1, 2, 3 and 4)




  1. Medical Devices Bulletin, March 1992, Vol. X, No. 3
  2. Olsen, W.P.L. Vanden Houten, and J.E. Ellis, “Sterile Vent filter Function Test” Journal of Parenteral Science and Technology, March-April 1981, Vol.35, No. 2, pp. 35-36.
  3. Port, F.K., and I.A. Bernstein, “Hepatitis Risk from Hemodialysis Pressure Monitors” Proceedings of the Third Meeting of ISAO, 1981, Supplement to Vol. 5, pp. 638-641.
  4. Vincent, M.E., and J.C. Glorioso, “Evaluation of Vacuum/Suction Safety Devices in Preventing Transmission of Human Virus Pathogens” American Clinical Laboratory, January 1989.
  5. Hinds, W.C., Aerosol Technology, A Wiley-Interscience Publication, 1982, p. 175.
  6. Ibid, p. 185.


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