APPENDIX B TO 7 CFR 1755.900-THERMAL
REEL WRAP QUALIFICATION

(I) The test procedures described in this appendix are only for qualification of initial and subsequent changes in thermal reel wraps.

(II) Sample selection. All testing must be performed on two 450 millimeter lengths of cable removed sequentially from the same fiber jacketed cable. This cable must not have been exposed to temperatures in excess of 38 °C since its initial cool down after sheathing.

(III) Test procedure. (1) Place the two samples on an insulating material such as wood. (2) Tape thermocouples to the jackets of each sample to measure the jacket temperature.

(3) Cover one sample with the thermal reel wrap.

(4) Expose the samples to a radiant heat source capable of heating the uncovered jacket sample to a minimum of 71 °C. A GE 600 watt photoflood lamp or an equivalent lamp having the light spectrum approximately that of the sun shall be used.

(5) The height of the lamp above the jacket shall be 380 millimeters or an equivalent height that produces the 71 °C jacket temperature on the unwrapped sample shall be used.

(6) After the samples have stabilized at the temperature, the jacket temperatures of the samples shall be recorded after one hour of exposure to the heat source.

(7) Compute the temperature difference between jackets.

(8) For the thermal reel wrap to be acceptable to RUS, the temperature difference between the jacket with the thermal reel wrap and the jacket without the reel wrap shall be greater than or equal to 17 °C.

[59 FR 34360, July 5, 1994; 59 FR 44795, Aug. 30, 1994]

$1755.910 RUS specification for outside plant housings and serving area interface systems.

(a) Scope. (1) The purpose of this specification is to inform manufacturers and users of outside plant housings and serving area interface (SAI) systems of the engineering and technical requirements that are considered necessary for satisfactory performance in outside plant environments. Included are the mechanical, electrical, and environmental requirements, desired design features, and test methods for evaluation of the product.

(2) The housing and terminal requirements reflect the best engineering judgment available at the present time and may be subject to change due to advances in technology, economic conditions, or other factors.

(3) The test procedures described in this section are required by RUS to demonstrate the functional reliability of the product. However, other standard or unique test procedures may serve the same function. In such cases, RUS shall evaluate the test procedures and results on an individual basis.

(4) The test procedures specified herein satisfy the requirements of housings as well as the requirements of terminals that may be installed within housings. Some of the requirements are interrelated to several tests designed to determine the performance aspects of terminals and are directly affected by testing required for housings. Therefore, the manufacturer should carefully review all the test requirements in order to develop a testing schedule that is comprehensive, efficient in terms of the number of test specimens required and can be accomplished in an orderly and logical sequence.

(5) The specified tests may require special facilities to comply with Federal, State, or local regulatory requirements. Some test procedures are poten

tially hazardous to personnel because of the high voltages and mechanical forces involved. Safety precautions are necessary to prevent injury.

(6) Underwriters Laboratories, Inc. (UL) 94, Tests for Flammability of Plastic Materials for Parts in Devices and Appliances, fourth edition, dated June 18, 1991, referenced in this section is incorporated by reference by RUS. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. A copy of the UL standard is available for inspection during normal business hours at RUS, room 2845-S, U.S. Department of Agriculture, Washington, DC 20250-1500 or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Copies are available from UL Inc., 333 Pfingsten Road, Northbrook, Illinois 60062-2096, telephone number (708) 272-8800.

(7) The American Society for Testing and Materials Specifications (ASTM) A 109-91, Standard Specification for Steel, Strip, Carbon, Cold-Rolled; ASTM A 153-82 (Reapproved 1987), Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware; ASTM A 366/A 366M-91, Standard Specification for Steel, Sheet, Carbon, Cold-Rolled, Commercial Quality; ASTM A 525-91b, Standard Specification for General Requirements for Steel Sheet, Zinc-Coated (Galvanized) by the Hot-Dip Process; ASTM A 526/A 526M-90, Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) by the Hot-Dip Process, Commercial Quality; ASTM A 569/A 569M-91a, Standard Specification for Steel, Carbon (0.15 Maximum, Percent), HotRolled Sheet and Strip Commercial Quality; ASTM A 621/A 621M-92, Standard Specification for Steel, Sheet and Strip, Carbon, Hot-Rolled, Drawing Quality; ASTM B 117-90, Standard Test Method of Salt Spray (Fog) Testing; ASTM B 539-90, Standard Test Methods for Measuring Contact Resistance of Electrical Connections (Static Contacts); ASTM B 633-85, Standard Specification for Electrodeposited Coatings of Zinc on Iron and Steel; ASTM D 52389, Standard Test Method for Specular Gloss; ASTM D 610-85 (Reapproved 1989), Standard Test Method for Evalu

ating Degree of Rusting on Painted Steel Surfaces; ASTM D 822-89, Standard Practice for Conducting Tests on Paint and Related Coatings and Materials using Filtered Open-Flame Carbon-Arc Light and Water Exposure Apparatus; ASTM D 1535-89, Standard Test Method for Specifying Color by the Munsell System; ASTM D 1654-92, Standard Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments; ASTM D 1693-70 (Reapproved 1988), Standard Test Method for Environmental Stress-Cracking of Ethylene Plastics; ASTM D 2197-86 (Reapproved 1991), Standard Test Method for Adhesion of Organic Coatings by Scrape Adhesion; ASTM D 2247-92, Standard Practice for Testing Water Resistance of Coatings in 100% Relative Humidity; ASTM D 2565-92, Standard Practice for Operating Xenon Arc-Type Light-Exposure Apparatus With and Without Water for Exposure of Plastics; ASTM D 2794-92, Standard Test Method for Resistance of Organic Coatings to the Effects of Rapid Deformation (Impact); ASTM D 3928-89, Standard Test Method for Evaluation of Gloss or Sheen Uniformity; ASTM D 4568-86, Standard Test Methods for Evaluating Compatibility Between Cable Filling and Flooding Compounds and Polyolefin Cable Materials; ASTM G 21-90, Standard Practice for Determining Resistance of Synthetic Polymeric Materials to Fungi; and ASTM G 23-90, Standard Practice for Operating Light-Exposure Apparatus (Carbon-Arc Type) With and Without Water for Exposure of Nonmetallic Materials, referenced in this section are incorporated by reference by RUS. These incorporations by references were approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 7 CFR part 51. Copies of the ASTM standards are available for inspection during normal business hours at RUS, room 2845-S, U.S. Department of Agriculture, Washington, DC 20250-1500 or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Copies are available from ASTM, 1916 Race Street, Philadelphia, Pennsylvania 19103-1187, telephone number (215) 299-5585.