Texas Comptroller of Public Accounts

Texas Comptroller of Public Accounts, Glenn Hegar

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Texas Specification No. 031-45-05A
(Supersedes Specification No. 031-45-05)
Effective Date: September 18, 1992
Revised Date: September 15, 2000


1. SCOPE: This specification establishes minimum requirements for replaceable air filter frames and pads, bulk roll filter media, and panel filter media.

2. APPLICABLE SPECIFICATIONS AND STANDARDS: References to specifications, standards and test methods shall be to the issues in effect on the date of the Invitation for Bids. Copies of the referenced documents may be obtained from the issuing organizations at the addresses shown. The following documents form a part of this specification to the extent specified herein:

2.1. AIR CONDITIONING AND REFRIGERATION INSTITUTE (ARI), 4301 N. Fairfax Drive, #425, Arlington, VA 22203, 703-524-8800, Fax: 703-528-3816, www.ari.org

2.1.1. ARI 850 -- Commercial and Industrial Air Filter Equipment.

2.2. AMERICAN SOCIETY OF HEATING, REFRIGERATING, AND AIR CONDITIONING ENGINEERS (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA 30329, (800) 527-4723, Fax: (404) 321-5478 www.ashrae.org

2.2.1. ANSI/ ASHRAE 52.1 -- Gravimetric and Dust-spot Procedures for Testing Air-Cleaning Devises Used in General Ventilation for Removing Particulate Matter.

2.3. FEDERAL DOCUMENTS: U.S. Government Printing Office, 8660 Cherry Lane, Laurel, MD 20707, (202) 512-1803, Fax: (202) 512-2168, www.access.gpo.gov

2.3.1. F-F-310 -- Filter, Air Conditioning: Viscous- Impingement and Dry Media, Replaceable.

2.4. UNDERWRITERS' LABORATORIES, INC. (UL), 333 Pfingsten Road, Northbrook, IL 60062-2096, (847) 272-8800, Fax: (847) 272-8129, www.ul.com

2.4.1. UL 900-1987 -- Air Filter Units.

2.5. GLOBAL ENGINEERING DOCUMENTS, Customer Support A105, 15 Inverness Way, Englewood, CO 80112, (800) 624-3974, Fax: (303) 792-2192, www.global.ihs.com.
2.5.1. Global Engineering Documents is an information specialist company that maintains and provides standards information for numerous organizations. Copies of standards may also be ordered from Global Engineering Documents.

3. CLASSIFICATION: Air filters shall be classified by type, grade, media thickness, and size as follows:

3.1. Types:

3.1.1. Type A: Air filter unit (Frame and Pad).

3.1.2. Type B: Filter Media, Roll Type. Type 1: Service roll, packed in dispenser carton, for cutting to size for permanent frames. Type 2: Bulk roll, for cutting to size for permanent frames.

3.1.3. Type C: Filter Pad, Flat Panel Type (Pre-cut).

3.2. Grade:

3.2.1. Grade A: Standard dust-holding capacity (commercial).

3.2.2. Grade B: High dust-holding capacity (industrial), for high velocity operations (exceeding 500 feet per minute).

3.3. Media:

3.3.1. Fiberglass.

3.3.2. Polyester.

3.4. Thickness:
3.4.1. One inch.

3.4.2. Two inches.

3.5. Size: Unless otherwise specified in the Invitation for Bids, dimensions shall be as shown in Tables 1, 2, and 3 for each Type. Thickness may be either one or two inches for each size as indicated.

4. DEFINITIONS: Terminology used in this specification is intended to be generic in nature and consistent with meanings that have been defined through general use and/or accepted trade practices. Where variant meanings may exist, the applicable interpretation shall be determined by the Texas Procurement and Support Services (TPASS).

4.1. Commission: Texas Procurement and Support Services.

4.2. Air Filter: The air cleaning device used for the removal of dust and other airborne particles from air circulated mechanically in equipment.

4.3. Synthetic Dust Weight Arrestance: The measure of the ability of a device to remove injected ASHRAE synthetic dust from the test air.

4.4. Atmospheric Dust Spot Efficiency: A measure of the ability of the device to remove atmospheric dust from the test air.

4.5. Class 1 Filter: Those which, when clean, do not contribute fuel when attacked by flame, and which emit only negligible amounts of smoke.

4.6. Class 2 Filter: Those which, when clean, burn moderately when attacked by flame or emit moderate amounts of smoke or both.

4.7. Media (Medium): That part of the device which is the actual dust removing agent.

5. REQUIREMENTS: Products furnished under this specification shall meet or exceed the following requirements:

5.1. General Requirements:

5.1.1. All filters shall be new, unused, and a currently standard product of an established manufacture except for such deviations as may be required by this specification.

5.1.2. Filters shall be free of all imperfections and/or defects which might affect appearance, normal life, or serviceability.

5.1.3. The filters shall be designed and fabricated for disposal when the dust load limit is reached.

5.1.4. The filter media shall be adhesive coated in accordance with the manufacturer's standard practice.

5.1.5. The filter media shall be non allergenic and non toxic.

5.1.6. Details not specified herein shall be in accordance with standard commercial practices for products of this type.

5.2. Registration: All filter units and media shall be rated Class 1 or Class 2 by Underwriters Laboratories, Inc. (UL 900) for flammability.

5.3. Design:

5.3.1. Filter Media: The filter media shall be graduated density, continuous filament fiberglass or polyester as specified in the Invitation for Bids. Fiberglass: Fiberglass media weight for one inch thick media shall be 10 grams minimum per square foot (dry). For two inch media, it may range from 20 to 35 grams, according to industry standards for medium to heavy duty filters. Polyester: Polyester media shall not contain voids or thin spots and shall provide strength in all directions. Fibers shall be interlocked. The media shall be manufactured of 100% non-woven polyester synthetic fibers.

Filter media shall be bonded together with a flame retardant thermosetting agent.

5.3.2. Adhesive: The media shall be coated with a non-toxic, non-migrating, non-flammable, odor-free adhesive, sufficient to cover all fibers uniformly.

5.3.3. Frame: The frames for Type A filter units shall be heavy duty kraft fiberboard or chipboard, of sufficient rigidity and securely bonded to the media.

5.3.4. Grille: Front and back metal grilles shall be provided for Type A filter units, minimum 28 gauge, with minimum 80% open area. The grilles shall be securely bonded to the frame, and be non-corrosive.

5.3.5. Backing: In lieu of a metal grille, commercial grade fiberboard or scrim backing may be used, whichever is the manufacturer's standard practice, provided that it is equivalent in strength and adhesion to the metal grille.

5.3.6. Type A Filters: With areas up to 500 square inches, a grille/backing may be provided on the downstream side only, if this is the manufacturer's standard practice. The backing shall meet the requirements of Paragraphs 5.3.4. and 5.3.5.

5.3.7. Roll Media: Type B filter media shall be of graduated density and be furnished with a rigid scrim or skin backing.

5.3.8. Pre-cut Filter Pads: Type C filter media shall be of graduated density and designed to fit securely into the owner's one or two inch metal frame.

5.3.9. Dimensions: Nominal sizes shall be subject to industry wide tolerances and sizing, as determined by the Air Conditioning and Refrigeration Institute (ARI). Actual sizes shall be listed on the manufacturer's specification sheets.

5.3.10. When so specified in the Invitation for Bids, stiffening bars shall be provided for heavy duty (Grade 8) filters.

5.4. Performance: Air filters shall meet or exceed the following requirements when tested according to ASHRAE 52.1, at 300 fpm face velocity.

5.4.1. Arrestance: Minimum values shall be as follows: Glass fiber media: 70% for one inch; 80% for two inch. Polyester fiber media: 80% for one inch; 85% for two inch.

5.4.2. Dust Holding Capacity: Grams per 24" x 24" face area, minimum values: Fiberglass: For one inch shall be 175 grams; for two inch shall be 200 grams. Polyester: For one inch shall be 140 grams; for two inch shall be 175 grams.

5.4.3. Efficiency: Minimum value of 20% for Type B bulk rolls and Type C pads.

5.5. Fabrication:

5.5.1. Edges: Air filters units and pads shall be constructed with 90 ° corners. Edges shall be parallel to within 1/16 of an inch.

5.5.2. Grille/Scrim: The media pad backing shall be of adequate rigidity not to cause displacement or distortion of the media when in heavy use.

5.5.3. Frames: Type A frames shall be of adequate rigidity to provide support during heavy usage, and shall be closed at all corners.

5.5.4. Separation: The media, frame, and/or retention materials shall be structurally sufficient to prevent any separation while installed or when in operation.

5.5.5. Sizing: Wood pulp products used for frame construction shall be sized to reduce moisture absorptivity.

5.6. Options: When so specified in the Invitation for Bids, filters shall be furnished with the following options:

5.6.1. Special size (See Paragraph 3.5.).

5.6.2. Class 1 (See Paragraph 4.3.).

5.6.3. Stiffening bars for air filter units, (See Paragraph 5.3.10.).

5.6.4. Fiberglass or polyester (See Paragraph 5.3.1.).

6. TESTING: Testing shall be done by, or at the direction of, the Commission and/or the receiving State agency. Test shall be performed on products from shipments to ordering agencies. In the event products tested fail to meet or exceed all conditions and requirements of this specification, the cost of the samples used and the cost of testing shall be borne by the supplier.

6.1. Certification: When so specified in the Invitation for Bids, independent laboratory certification that the filters meet the requirements of Paragraph 5.4. shall be submitted.

7. SAMPLES: Unless otherwise specified in the Invitation for Bids, no prepurchase samples shall be required. Samples tested shall be obtained from products supplied on regular orders.

8. INSPECTION: Products furnished under this specification shall be inspected by, or at the direction of the Commission and/or the ordering State agency either at the destination or place of manufacture.

9. WARRANTY: All filters shall carry the manufacturer's standard warranty and shall be guaranteed against defects in materials, workmanship, and performance for a minimum of one year. The warranty shall begin on the date of acceptance of the unit by the ordering agency. During this warranty period, the vendor shall repair or replace defective components/units at no cost to the State of Texas.

10. PACKING/PACKAGING: Packaging for shipment shall be in accordance with the manufacturer's standard practice and in a manner readily accepted by common carriers engaged in interstate commerce. Within the shipping carton, units shall be packed in a manner designed to minimize damage during shipment due to rough or improper handling.


11.1. Marking: Each shipping container shall be clearly marked with the following:

11.1.1. Name of contents, including brand name, if any.

11.1.2. Quantity.

11.1.3. Name and address of the manufacturer.

The following information shall either be marked on the container or appear on the shipping documents:

11.1.4. Order number or contract number.

11.1.5. Name and address of ordering agency.

11.1.6. Agency requisition number.

11.2. Labeling: Each air filter unit or filter container shall be labeled with the manufacturer's name, model number or equivalent, filter size, and UL approval category.

11.2.1. Each unidirectional filter/filter media shall be marked to show direction of airflow.

12. BID LITERATURE: Bidder shall submit complete and illustrated description of the products being offered.

13. COMPLIANCE: In order for consideration to be given to the bid on an item under this specification, the bidder must comply with the following conditions:

13.1. PRODUCT IDENTIFICATION: The make, model number, name of the manufacturer, brand or trade name, etc., as applicable, of the item which the vendor proposes to furnish must be stated as part of the bid.

13.2. EXCEPTIONS: Notwithstanding the above, any exception taken by the bidder to the requirements and conditions of this specification must be stated and described in detail as a part of the bid. If no exceptions or deviations are identified in this manner, the items must be furnished exactly as described herein.

13.3. PROOF: The bidder shall bear the burden of proof of compliance with this specification.

13.4. BID RESPONSE: When so specified in the Invitation for Bids, bidders shall provide a line by line response to all technical items in Paragraph 5.

13.5. CERTIFICATION: See Paragraph 6.1.

14. PRODUCT INFORMATION: Polyester synthetic media is recommended for those areas where a higher degree of air cleanliness is required.

15. ORDERING DATA: When ordering a product conforming to this specification, the requisitioning agency must specify the following:

15.1. The number of this specification (031-45-05A).

15.2. Type (See Paragraph 3.1.).

15.3. Grade (See Paragraph 3.2.).

15.4. Media (See Paragraph 3.3.).

15.5. Thickness (See Paragraph 3.4.).

15.6. Size (See Paragraph 3.5.).

15.7. Options (See Paragraph 5.6.).

15.8. Quantity of each type, grade, media, thickness, and size required.

16. AVAILABILITY OF SPECIFICATIONS: Copies of this specification may be obtained from our Web site or by writing or calling:
Bid Services
Texas Procurement and Support Services
P. O. Box 13186
Austin, TX 78711-3047
(512) 463-3416


Thickness Size
One Inch (1")
Thickness Size
Two Inches (2")
8 X 16
10 X 10 10 X 10
10 X 20 10 X 20
10 X 24
10 X 25
10 X 30
12 X 20
12 X 24 12 X 24
12 X 25
12 X 30
14 X 20
14 X 25
15 X 20 15 X 20
15 X 30-5/8
16 X 16
16 X 20 16 X 20
16 X 22-1/4
16 X 25 16 X 25
18 X 25
19 X 27
20 X 20 20 X 20
20 X 24 20 X 24
20 X 25 20 X 25
22 X 22
24 X 24 24 X 24
25 X 25 25 X 25

SIZE: TYPE B (Type 1)

Thickness Size
One Inch (1")
Thickness Size
Two Inches (2")
20 X 240 20 X 240
24 X 240 24 X 240
28 X 240
30 X 240 30 X 240
36 X 240 36 X 240
40 X 240 40 X 240
44 X 240

TYPE B (Type 2)

Thickness Size
One Inch (1")
Thickness Size
Two Inches (2")
20 20
25 25
30 30
36 36
40 40
60 60


Thickness Size
One Inch (1")
Thickness Size
Two Inches (2")
16 16
20 20
25 25
40 40
60 60


Filter Pads
Thickness Size
One Inch (1")
Filter Pads
Thickness Size
Two Inches (2")
16 x 20 16 x 20
16 x 25 16 x 25
20 x 20 20 x 20
20 x 25 20 x 25
24 x 24 24 x 24

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