Texas Comptroller of Public Accounts

Texas Comptroller of Public Accounts, Glenn Hegar

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Texas Specification No. 505-57-03B

Effective Date: August 30, 1985

Reformatted: January 29, 1996




1. SCOPE: This specification covers the minimum requirements for a laundry alkali known in the chemical trade as sodium orthosilicate, which is actually an intimate mixture of sodium metasilicate and sodium hydroxide.

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. AMERICAN SOCIETY FOR TESTING MATERIALS, 1916 Race Street, Philadelphia, PA 19103:

2.1.1. ASTM D 501 -- Standard Methods of Sampling and Chemical Analysis of Soaps and Other Detergents.

2.1.2. ASTM D 502 -- Standard Method of Test for particle Size of Soaps and Other Detergents.

2.1.3. ASTM D 1172 -- Standard Method of Test for pH of Aqueous Solutions of Soaps and Detergents.

2.2. LINEN SUPPLY ASSOCIATION OF AMERICA, 1250 East Hallandale Beach Boulevard, Hallandale, FL 33009:

2.2.1. Textile Laundering Technology, 1979, by Riggs, Charles L. and Sherrill, Joseph C.

2.3. TEXAS SPECIFICATIONS: General Services Commission, P.O. Box 13186, Austin, TX 78711:

2.3.1. Texas Specification No. 505-57-01B -- Laundry Alkali -- Sodium Metasilicate.

2.3.2. Texas Specification No. 505-57-02A -- Caustic Soda (Lye), Anhydrous (Sodium Hydroxide).

3. 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).

3.1. Commission: Texas Procurement and Support Services (TPASS).

4. REQUIREMENTS: Sodium Orthosilicate furnished under this specification shall meet or exceed the following minimum requirements:

4.1. General Requirements: The product shall be free flowing granular material, white in color, with no objectionable odor or tendency to raise irritating dust. It shall be suitable for the intended use as a laundry alkali.

4.2. Chemical COMPOSITION: The product shall be a uniformly blended mixture of anhydrous particles of sodium metasilicate and sodium hydroxide in a 3:2 ratio by weight. A small amount (not to exceed 0.3%) of a highly refined light mineral oil may also be present in order to diminish the amount of dust during handling.

4.3. PRODUCT REQUIREMENTS: The product shall conform to the requirements of Table 1, when tested by the methods cited in Paragraph 6.



Requirement Minimum Maximum Test Paragraph
1. Total alkalinity as Na2O, pbw* 60.0 -- 6.1
2. Silica as SiO2, pbw* 27.0 -- 6.2
3. Carbonate as CO2, pbw* -- 1.9 6.3
4. Water insoluble matter, pbw* -- 0.6 6.40
5. pH in 1% aqueous solution 12.8 -- 6.5
6. Particle size, pbw* passing
No. 8 standard sieve (2.36 mm) 99.00 -- 6.60
No. 80 standard sieve (180 mm) -- 5.00 6.60
*pbw: percent by weight

5. SAMPLES: Unless otherwise specified in the Invitation for Bids, no prepurchase samples shall be required. Samples tested shall be taken from regular orders.

6. TESTING: Testing shall be done by or at the direction of, the Commission and/or the receiving State agency. Tests 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. TESTS: The product furnished under this specification shall be tested by the following methods or equally applicable procedures:

6.1.1. Total Alkalinity: Determine compliance with Paragraph 4.2. by the procedure of ASTM 501, Paragraphs 47 through 49.

6.1.2. Silica: Determine compliance with Paragraph 4.2 by the procedure of ASTM D 501, Paragraphs 50 through 52.

6.1.3. Carbonate: Determine compliance with Paragraph 4.2 by the procedure of ASTM D 501, Paragraphs 12 through 15.

6.1.4. Water Insoluble Matter: Determine compliance with Paragraph 4.2 by the procedure of ASTM D 501, Paragraphs 55 and 56.

6.1.5. pH: Determine compliance with Paragraph 4.2 by the procedure of ASTM D 1172, with the exception that a 10 gram sample weighed to the nearest 0.1 gram shall be used.

6.1.6. Particle Size: Determine the compliance with Paragraph 4.2 by the procedure of ASTM D 502, with the exception of the screen sizes required.

7. 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.

8. PACKING / PACKAGING: Packing 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 the shipment because of rough or improper handling.

8.1. PACKING: The product shall be packaged for shipment in one of the following types of containers, whichever is specified in the Invitation for Bids:

8.1.1. 55 pound moisture resistant multiwall paper bags*.

8.1.2. 100 pound moisture resistant multiwall paper bags.

8.1.3. 400 pound plastic lined fiber drums approved for this use by the U.S. Department of Transportation.

Note: Vendors furnishing this product in 55 pound bags shall furnish total amounts as close as possible to the amount ordered. (For example, if the order specifies 10,000 pounds, the vendor shall furnish 182 bags or 10, 010 pounds. bids will be awarded to the lowest bidder on a per pound basis.)


9.1. MARKING: Each shipping container shall be clearly marked with the following:

9.1.1. Name of contents.

9.1.2. Quantity ordered.

9.1.3. Name and address of the manufacturer.

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

9.1.4. Order number or contract number.

9.1.5. Name and address of ordering agency.

9.1.6. Agency requisition number.

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

10.1. 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.

10.2. 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.

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

11. ORDERING DATA: When ordering products conforming to this specification the requisitioning agency shall specify the following:

11.1. The number of this specification (505-57-03B).

11.2. Size and type of container required.

11.3. The total quantity required.


12.1. Caution: Any of these strong alkalis can cause irritation or serious injury unless promptly washed off with running water. In case of accidental swallowing, the patient should drink a large amounts of water containing about an ounce of vinegar. A physician should be called immediately.

12.2. Other Sources of Sodium Orthosilicate: The inaccurate term "sodium orthosilicate" refers in the trade to a mechanical mixture of two parts of sodium metasilicate and one part sodium hydroxide. These two alkalis are obtainable separately under Texas Specifications, and will give the same results when mixed in the correct proportions, possibly at a lower cost.

12.3. Product Use: A product conforming to this specification is one of the strongest laundry alkalis available under Texas Specifications. It is recommended for use in laundering fabrics belonging to the heavy soil and very heavy soil classifications (see Riggs and Sherrill, page 94). This includes diapers and fabrics soiled with animal fats and greases.

13. AVAILABILITY OF SPECIFICATIONS: Copies of this specification may be obtained by calling or writing:

Bid Services

Texas Procurement and Support Services

P.O.Box 13186

Austin, TX 78711-3047

(512) 463-3416

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