W912HV25B0003 AM-0002_Specs.pdf

FY24 REPLACE AMERICAN FORCES NETWORK (AFN) RADIO TRANSMISSION 24MC0004

TOWER, CAMP KINSER, OKINAWA, JAPAN

SECTION TABLE OF CONTENTS

DIVISION 09 - FINISHES

SECTION 09 97 13.25

MAINTENANCE, REPAIR, AND COATING OF TALL ANTENNA TOWERS

05/11, CHG 1: 08/17

PART 1 GENERAL

1.1 REFERENCES

1.2 MODIFICATIONS TO REFERENCES

1.3 DESCRIPTION OF WORK

1.4 SUBMITTALS

1.5 SAFETY

1.6 DELIVERY, STORAGE AND HANDLING

1.6.1 Coating Materials

1.6.2 Structural and Miscellaneous Materials

1.7 COATING HAZARDS

1.8 JOB SITE REFERENCES

1.9 PRE-APPLICATION MEETING

1.10 QUALITY ASSURANCE

1.10.1 Drawings: Steel Fabrication

1.10.2 Design Data: Coating System

1.10.3 Certificates

1.10.3.1 Work Plan

1.10.3.2 Qualifications of Certified Industrial Hygienist (CIH)

1.10.3.3 Qualifications of Testing Laboratory for Coatings

1.10.3.4 Qualifications of Testing Laboratory for Abrasive Media

1.10.3.5 Qualifications of Coating Contractors

1.10.3.6 Not Used

1.10.3.7 Abrasive Media

1.10.3.8 Coating System Compatibility

1.10.4 Test Reports

1.10.4.1 Non-metallic Abrasive Media

1.10.4.2 Coatings

1.10.4.3 Metallic Abrasive Media

1.10.4.4 Daily Inspection Checklist

1.10.4.5 Recycled Metallic Abrasive Media

PART 2 PRODUCTS

2.1 STEEL

2.1.1 Structural and Miscellaneous Steel

2.1.2 Steel Tubing and Pipe

2.2 BOLTS, NUTS, AND WASHERS

2.2.1 Structural Steel

2.2.1.1 Bolts

2.2.1.2 Nuts

2.2.1.3 Washers

2.2.1.4 Load Indicator Washers

2.3 GALVANIZING

2.3.1 Galvanizing Repair Compound

2.4 WELDING

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2.4.1 Exothermic Weld Kits

2.5 COATING SYSTEM

2.5.1 Epoxy Intermediate Coat

2.5.2 Polyurethane Topcoat

2.6 SOLUBLE SALTS TEST KITS

2.6.1 Test Kit for Measuring Chlorides on Steel Surfaces

2.6.2 Test Kit for Measuring Chlorides in Abrasives

2.7 ABRASIVE MEDIA

2.7.1 Non-metallic Abrasive Media

2.7.2 Metallic Abrasive Media

2.7.2.1 New and Remanufactured Metallic Abrasive Media

2.7.2.2 Recycled Metallic Abrasive Media

PART 3 EXECUTION

3.1 STRUCTURAL

3.1.1 Fabrication

3.1.1.1 Measurements

3.1.1.2 Metal Surfaces

3.1.1.3 Construction

3.1.1.4 Fastening

3.1.1.5 Shop Fabrication

3.1.2 Galvanizing

3.1.3 Welding

3.1.3.1 Exothermic Welding

3.1.4 Connections

3.1.4.1 Bolts

3.1.4.2 Installation of Load Indicator Washers (LIW)

3.2 COATING SAMPLING AND FIELD TESTING

3.2.1 Coating Sample Collection

3.2.2 Coating Sample Testing

3.3 SURFACES TO BE COATED

3.3.1 Protection of Items not to be Painted

3.4 ACCEPTABLE INSTALLERS

3.5 LIGHTING

3.6 SURFACE PREPARATION

3.6.1 Abrasive Blasting Equipment

3.6.2 Abrasives for Soluble Salts Contamination

3.6.2.1 Pre-Preparation Testing of Abrasive Media Shipped in Bulk

Containers

3.6.2.2 Abrasive Media Shipped in Bags (Nominal 50-110 lb.)

3.6.2.3 Operational Testing of Recycled Metallic Abrasive Media

3.6.3 Clean

3.6.4 Surface Standard

3.6.5 Pre-Preparation Testing for Surface Contamination

3.6.5.1 Pre-Preparation Testing for Oil and Grease Contamination

3.6.5.2 Pre-Preparation Testing for Soluble Salts Contamination

3.6.6 Abrasive Blasting

3.6.7 Pre-Application Testing For Surface Contamination

3.6.7.1 Pre-Application Testing for Oil and Grease Contamination

3.6.7.2 Pre-Application Testing for Soluble Salts Contamination

3.6.7.3 Pre-Application Testing for Surface Cleanliness

3.7 MIXING AND APPLICATION OF COATING SYSTEM

3.7.1 Preparation of Coating Materials for Application

3.7.1.1 Mixing Intermediate and Topcoat Materials

3.7.1.2 Pot Life

3.7.1.3 Application Conditions and Recoat Windows

3.7.2 Application of Coating System

3.7.2.1 Application of Intermediate Coat

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3.7.2.2 Application of Topcoat

3.7.2.3 Procedure for Making Spot Repairs

3.8 FIELD TESTS AND INSPECTION

3.8.1 NACE Coating Inspector

3.8.2 Field Inspection

3.8.2.1 Thickness Testing

3.8.3 Hold Points for Quality Control Inspections

3.9 ELECTRICAL WORK

3.9.1 Terminating Aluminum Stranded Conductors

3.10 FINAL CLEANUP

ATTACHMENTS:

daily inspection checklist

-- End of Section Table of Contents --

W912HV-25-B-0003 SECTION 09 97 13.25 Page 3 AM-0002

SECTION 09 97 13.25

MAINTENANCE, REPAIR, AND COATING OF TALL ANTENNA TOWERS

05/11, CHG 1: 08/17

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AMERICAN INSTITUTE OF STEEL CONSTRUCTION (AISC)

AISC 303 (2016) Code of Standard Practice for Steel Buildings and Bridges

AISC 325 (2017) Steel Construction Manual

AISC 326 (2009) Detailing for Steel Construction

AISC 360 (2016) Specification for Structural Steel Buildings

AMERICAN WELDING SOCIETY (AWS)

AWS D1.1/D1.1M (2020; Errata 1 2021) Structural Welding Code - Steel

ASTM INTERNATIONAL (ASTM)

ASTM A123/A123M (2017) Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products

ASTM A153/A153M (2023) Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware

ASTM A325 (2014) Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength

ASTM A563 (2021; E 2022a) Standard Specification for Carbon and Alloy Steel Nuts

ASTM A780/A780M (2020) Standard Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings

ASTM D1200 (2010; R 2014) Viscosity by Ford Viscosity Cup

ASTM D1640/D1640M (2014) Standard Test Methods for Drying, Curing, or Film Formation of Organic Coatings

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ASTM D3335 (1985a; R 2020) Low Concentrations of Lead, Cadmium, and Cobalt in Paint by Atomic Absorption Spectroscopy

ASTM D3718 (1985a; R 2015) Low Concentrations of Chromium in Paint by Atomic Absorption Spectroscopy

ASTM D3925 (2002; R 2015) Sampling Liquid Paints and Related Pigmented Coatings

ASTM D4285 (1983; R 2018) Indicating Oil or Water in Compressed Air

ASTM D4417 (2021) Standard Test Methods for Field Measurement of Surface Profile of Blast Cleaned Steel

ASTM F436 (2011) Hardened Steel Washers

ASTM F959/F959M (2017a) Standard Specification for Compressible-Washer-Type Direct Tension Indicators for Use with Structural Fasteners, Metric Series

JAPANESE ARCHITECTURAL STANDARD SPECIFICATIONS (JASS)

JASS 6 (2015) Structural Steelwork Specification for Building Construction

JASS 18 (2015) Specification for Water-based Anticorrosive Painting Work

JAPANESE INDUSTRIAL STANDARDS (JIS)

JIS B 1186 (2013) Sets Of High Strength Hexagon Bolt, Hexagon Nut and Plain Washers for Friction Grip Joints

JIS B 1048 (2007) Fasteners - Hot Dip Galvanized Coatings

JIS G 3106 (2022) Rolled Steels for Welded Structure (Amendment 1)

JIS G 3136 (2022) Rolled Steels for Building Structure

JIS G 3444 (2021) Carbon Steel Tubes for General Structure

JIS H 8641 (2007) Hot Dip Galvanized Coatings

JIS K 5659 (2018) Weather-Resistant Paint For Steel Structures

NACE INTERNATIONAL (NACE)

NACE SP0288 (2011) Inspection of Linings on Steel and

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Concrete Equipment

RESEARCH COUNCIL ON STRUCTURAL CONNECTIONS (RCSC)

RCSC A348 (2020) RCSC Specification for Structural Joints Using High-strength Bolts

SOCIETY FOR PROTECTIVE COATINGS (SSPC)

SSPC 7/NACE No.4 (2007) Brush-Off Blast Cleaning

SSPC AB 2 (2015; E 2016) Cleanliness of Recycled Ferrous Metallic Abrasive

SSPC AB 3 (2003; E 2004) Ferrous Metallic Abrasive

SSPC Guide 12 (2023) Guide for Illumination of Industrial Painting Projects

SSPC PA 1 (2016) Shop, Field, and Maintenance Coating of Metals

SSPC PA 2 (2015; E 2018) Procedure for Determining Conformance to Dry Coating Thickness Requirements

SSPC SP 1 (2015) Solvent Cleaning

SSPC SP 10/NACE No. 2 (2015) Near-White Blast Cleaning

SSPC SP COM (2016; E 2017) Surface Preparation Commentary for Steel and Concrete Substrates

SSPC VIS 1 (2002; E 2004) Guide and Reference Photographs for Steel Surfaces Prepared by Dry Abrasive Blast Cleaning

SOCIETY OF AUTOMOTIVE ENGINEERS INTERNATIONAL (SAE)

SAE AMS-STD-595A (2017) Colors used in Government Procurement

U.S. DEPARTMENT OF DEFENSE (DOD)

MIL-A-22262 (1993; Rev B; Am 1 1994; Am 2 1996; Notice 1 2021) Abrasive Blasting Media Ship Hull Blast Cleaning

MIL-DTL-24441 (2009; Rev D; Notice 1 2021) Paint, Epoxy-Polyamide, General Specification for

MIL-DTL-24441/19 (2009; Rev C; Notice 1 2023) Paint, Epoxy-Polyamide, Zinc Primer, Formula 159, Type III

MIL-DTL-24441/31 (2009; Rev B; Notice 1 2021) Paint, Epoxy-Polyamide, White, Formula 152, Type

IV

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MIL-PRF-85285 (2022; Rev F) Topcoat, Aircraft and Support Equipment

U.S. NATIONAL ARCHIVES AND RECORDS ADMINISTRATION (NARA)

29 CFR 1910.134 Respiratory Protection

29 CFR 1910.1000 Air Contaminants

29 CFR 1926.59 Hazard Communication

1.2 MODIFICATIONS TO REFERENCES

In AISC 325 , AISC 360 , AISC 303 , and RCSC A348, except as modified in this section, shall be considered a part of AISC 325 and is referred to in this section as AISC 325 .

1.3 DESCRIPTION OF WORK

The project entail construction of a new 300 foot cylindrical tower for Amplitude Modulation (AM) antenna system. The tower will sit on a concrete foundation and will be supported by guy wires. Provide a brief description of the work to be covered by this specification.

1.4 SUBMITTALS

Government approval is required for submittals with a "G" or "S" classification. Submittals not having a "G" or "S" classification are for Contractor Quality Control approval. Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

Steel Fabrication; G

SD-03 Product Data

Exothermic Weld Kits; G

Load Indicator Washers; G

SD-06 Test Reports

Non-metallic Abrasive Media; G

Coatings; G

Bolts, Nuts, and Washers; G

Supply the certified manufacturer's mill reports which clearly show the applicable ASTM mechanical and chemical requirements together with the actual test results for the supplied fasteners.

Metallic Abrasive Media; G

Daily inspection checklist; G

Coating Sample Testing; G

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Recycled Metallic Abrasive Media; G

SD-07 Certificates

Coating System; G

Abrasive Media; G

Coating System Compatibility; G

Galvanizing; G

Bolts, Nuts, and Washers; G

Work plan; G

Qualifications of Certified Industrial Hygienist (CIH); G

Qualifications of Testing Laboratory for Coatings; G

Qualifications of Testing Laboratory for Abrasive Media; G

Qualifications of Coating Contractors; G

SD-08 Manufacturer's Instructions

Coating system; G

1.5 SAFETY

The Contractor shall submit an Accident Prevention Plan as per Section

01 35 26 GOVERNMENTAL SAFETY REQUIREMENTS.

1.6 DELIVERY, STORAGE AND HANDLING

1.6.1 Coating Materials

Ship, store and handle materials in accordance with SSPC PA 1. Maintain temperature in storage spaces between 5 and 24 degrees C. Maintain ambient air temperature more than 3 degrees C above the dew-point at all times. During mixing of polyurethane materials, maintain relative humidity below 90 percent.

1.6.2 Structural and Miscellaneous Materials

Handle, store, and protect materials in accordance with the manufacturer's recommendations. Replace damaged items with new items, or repair as approved by the Contracting Officer.

1.7 COATING HAZARDS

Ensure that employees are trained in all aspects of the safety plan.

Specified coatings may have potential health hazards if ingested or improperly handled. The coatings manufacturer's written safety precautions shall be followed throughout the mixing, application, and curing of the coatings. During tank cleaning, cleanup, surface preparation, and paint application phases, ensure that employees are adequately protected from toxic and hazardous chemical agents which exceed

W912HV-25-B-0003 SECTION 09 97 13.25 Page 8 AM-0002 the concentrations in OSHA 29 CFR 1910.1000 . Comply with respiratory protection requirements in OSHA 29 CFR 1910.134 . Obtain the services of a certified industrial hygienist to review and approve the operations as to correctness of work procedures and personal protective equipment.

1.8 JOB SITE REFERENCES

Make available to the Contracting Officer at least one copy each of

ASTM D3925, ASTM D4285, ASTM D4417, NACE SP0288, SSPC SP COM, SSPC SP 1 ,

SSPC SP 10/NACE No. 2 , SSPC PA 1 , SSPC PA 2 , SSPC Guide 12 , and SSPC VIS 1 at the job site.

1.9 PRE-APPLICATION MEETING

Prior to any surface preparation or coating operations, Contractor representatives, including at a minimum, project superintendent and QC manager, paint foreman, Contracting Officer representatives, coating inspector shall have a pre-application tank coating preparatory meeting.

This meeting shall be in addition to the pre-construction conference.

Specific items to be addressed shall include: the work plan, the safety plan, inspection standards, inspector qualifications and tools, test procedures, environmental control system, safety plan, and test logs.

Notify the Contracting Officer 10 days prior to meeting.

1.10 QUALITY ASSURANCE

1.10.1 Drawings: Steel Fabrication

Submit fabrication drawings for approval prior to fabrication. Prepare in accordance with AISC 326 and AISC 325 . Drawings shall not be reproductions of contract drawings. Include complete information for the fabrication and erection of the structure's components, including the location, type, and size of bolts, welds, member sizes and lengths, connection details, blocks, copes, and cuts. Use AWS standard welding symbols.

1.10.2 Design Data: Coating System

Submit manufacturer's printed instructions including detailed mixing and application procedures, number and types of coats required, minimum and maximum application temperatures, and curing procedures. Include Safety Data Sheets (SDS) for materials to be used at the job site in accordance with 29 CFR 1926.59 .

1.10.3 Certificates

1.10.3.1 Work Plan

A specific written plan describing in detail all phases of coating operations. For coating work, address work sequencing, surface preparation, coating application, recoat and cure time projections, as well as how each step will be controlled, tested, and evaluated. Address safety measures, work scheduling around weather, and record keeping.

1.10.3.2 Qualifications of Certified Industrial Hygienist (CIH)

Submit name, address, telephone number, FAX number, and e-mail address of the independent third party CIH. Submit documentation that hygienist is certified by the American Board of Industrial Hygiene in comprehensive

W912HV-25-B-0003 SECTION 09 97 13.25 Page 9 AM-0002 practice, including certification number and date of certification/recertification. Provide evidence of experience with hazards involved in industrial coating application work.

1.10.3.3 Qualifications of Testing Laboratory for Coatings

Submit name, address, telephone number, FAX number, and e-mail address of the independent third party laboratory selected to perform testing of the coating samples for compliance with specification requirements. Submit documentation that laboratory is regularly engaged in testing of paint samples for conformance with specifications, and that persons performing analyses are qualified.

1.10.3.4 Qualifications of Testing Laboratory for Abrasive Media

Submit name, address, telephone number, FAX number, and e-mail address of the independent third party laboratory selected to perform the testing of the abrasive media samples for compliance with specification requirements. Submit documentation that laboratory has experience in testing samples of abrasive media for conformance with specifications, and that persons performing analyses are qualified.

1.10.3.5 Qualifications of Coating Contractors

Submit the name, address, telephone number, FAX number, and e-mail address of the agency that will be performing all surface preparation and coating application. Submit evidence that key personnel have successfully performed surface preparation and application of coatings in accordance with the requirements of JASS 18 on a minimum of three separate projects within the past three years. List information by individual and include the following:

a. Name of individual and proposed position for this work.

b. Information about each previous assignment including:

Position or responsibility Employer (if other than the Contractor) Name of facility owner Mailing address, telephone number, and telex number (if non-US) of facility owner Name of individual in facility owner's organization who can be contacted as a reference Location, size and description of structure Dates work was carried out Description of work carried out on structure

1.10.3.6 Not Used

1.10.3.7 Abrasive Media

Certify conformance to contract requirements and provide copies of test results required by MIL-A-22262 or SSPC AB 3 for material chosen.

1.10.3.8 Coating System Compatibility

Provide certification from each manufacturer of components of the coating system, epoxy intermediate, and polyurethane topcoat, that the supplied

W912HV-25-B-0003 SECTION 09 97 13.25 Page 10 AM-0002 coating material is suitable for use in the specified coating system.

Each manufacturer shall identify the specific products, including manufacturer's name, which their product may be used with. The certification shall provide the name of the manufacturer that will provide technical support for the entire system. When all coating materials are manufactured by one manufacturer, this certification is not required.

1.10.4 Test Reports

1.10.4.1 Non-metallic Abrasive Media

Submit test results from independent laboratory of representative sample of abrasive media. Sample must have been tested within the last three years. Submit results as required in article entitled "QUALIFICATION INSPECTION" of MIL-A-22262 , and as revised by article entitled "ABRASIVE MEDIA" herein. Note that requirement for "QUALIFICATION INSPECTION" is a pre-qualification requirement, and involves the same testing required for listing in the Qualified Products List of the respective material. See appropriate Military Specification for specific test requirements.

1.10.4.2 Coatings

Submit test results from independent laboratory of representative samples of each coating material. Samples must have been tested within the last three years. Submit results for epoxy materials as required in article entitled "QUALIFICATION INSPECTION" of MIL-DTL-24441 , and as revised by article entitled "COATING SYSTEM" herein. Submit results for polyurethane materials as required in article entitled "QUALIFICATION INSPECTION" of MIL-PRF-85285 , and as revised by article entitled "COATING SYSTEM" herein. Note that requirement for "QUALIFICATION INSPECTION" is a pre-qualification requirement, and involves the same testing required for listing in the Qualified Products List of the respective material. See appropriate Military Specification for specific test requirements.

1.10.4.3 Metallic Abrasive Media

Submit test results from independent laboratory testing of sample of each batch delivered to job site.

1.10.4.4 Daily Inspection Checklist

Submit one copy of daily inspection checklist, completed each day when performing work under this section, to the Contracting Officer. Submit within 24 hours of date recorded on the checklist.

1.10.4.5 Recycled Metallic Abrasive Media

Submit test results from independent laboratory of daily and weekly Quality Control testing required by SSPC AB 2 , as modified in article entitled "ABRASIVE MEDIA."

PART 2 PRODUCTS

2.1 STEEL

New steel shall be galvanized.

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2.1.1 Structural and Miscellaneous Steel

Wide flange and WT shapes, JIS G 3136 , SN490B, 325 MPa. Angles and Channels JIS G 3106 , SM400, 235 MPa. Plates, JIS G 3136 , SN490B, 325 MPa. All hot dip galvanized.

2.1.2 Steel Tubing and Pipe

JIS G 3444 , STK400, 235 MPa, hot dip galvanized.

2.2 BOLTS, NUTS, AND WASHERS

Provide the following unless indicated otherwise.

2.2.1 Structural Steel

2.2.1.1 Bolts

ASTM A325, Type 1, hot dip galvanized or JIS B 1186 , Type F8T. Bolts shall have a maximum Rockwell hardness of 32. The bolt heads and the nuts of the supplied fasteners must be marked with the manufacturer's identification mark, the strength, grade and type specified by ASTM specifications.

2.2.1.2 Nuts

Provide galvanized ASTM A563 or JIS B 1186 , F10 nuts, Grade and Style as specified in the applicable ASTM standard. Provide ASTM A563 or JIS B 1186 , F10, hot dip galvanized nuts with a locking pin set in the nut. The locking pin shall slide along the bolt threads, and by reversing the direction of the locking pin, the nut shall be removed without damaging the nut or bolt. Provide noncorrosive locking pins.

2.2.1.3 Washers

ASTM F436 or JIS B 1186 , F35, hot dip galvanized steel.

2.2.1.4 Load Indicator Washers

ASTM F959/F959M , hot dip galvanized steel.

2.3 GALVANIZING

ASTM A123/A123M or ASTM A153/A153M , and JIS H 8641 or JIS B 1048 as applicable, unless specified otherwise. GALVANIZED SURFACES SHALL NOT BE

"PASSIVATED" OR "STABILIZED".

2.3.1 Galvanizing Repair Compound

ASTM A780/A780M or JASS 6 , cold galvanizing repair compound.

2.4 WELDING

AWS D1.1/D1.1M for steel.

2.4.1 Exothermic Weld Kits

Exothermic weld kits specifically designed by the manufacturer for welding the types of materials and shapes provided.

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2.5 COATING SYSTEM

Alternate systems or products will not be considered. Provide primer per

JASS 18 .

2.5.1 Epoxy Intermediate Coat

Provide intermediate coating per JIS K 5659 or Epoxy polyamide, MIL-DTL-24441/31 (Formula 152, Type IV, White (Tinted)). Tint to approximately SAE AMS-STD-595A color number 27778 parchment using pigment dispersions prepared for epoxy paint tinting. Manufacturer shall tint material and appropriately label. Modify requirements to include maximum allowable lead content of 0.06 percent by wt. as tested by ASTM D3335, maximum Cadmium content of 0.06 percent by wt. as tested by ASTM D3335, and maximum allowable Chromium content of 0.00 percent by wt. as tested by ASTM D3718. All other requirements of this Military Specification apply.

2.5.2 Polyurethane Topcoat

Provide top coat per JIS K 5659 or Polyurethane coating topcoat of MIL-PRF-85285 , Type II, White SAE AMS-STD-595A color number 17875, and Orange color number 12197.

Modify paragraph 3.6.4 of MIL-PRF-85285 , Viscosity and Pot Life, as follows:

The viscosity of the admixed coating, when tested in accordance with ASTM D1200 through a No. 4 Ford cup, shall be as follows:

Time from mix (minimum) Maximum time through a No. 4 Ford cup

Initially 30 seconds

2 hours 60 seconds

4 hours No gel

Modify paragraph 3.7.1 of MIL-PRF-85285 , Drying Time, as follows:

When applied by spray techniques and when tested in accordance with ASTM D1640/D1640M , the coating shall be set-to-touch within four hours and dry-hard within eight hours (see 4.6 and table I).

All other requirements of this Military Specification apply.

2.6 SOLUBLE SALTS TEST KITS

2.6.1 Test Kit for Measuring Chlorides on Steel Surfaces

Provide test kits to be considered for approval. Each proposed test kit shall:

a. Be a completely self-contained test kit with all materials, supplies, tools and instructions to take tests and identity results;

b. Use identifiable, consistent, factory pre-measured test extract solution;

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c. Provide for testing of any steel surface, regardless of orientation;

d. Provide for testing flat, curved, smooth, pitted and rough surfaces;

e. Provide for taking direct measurements of the chloride ion in micrograms per square centimeter without using conversion charts or tables;

f. Be environmentally friendly and not contain any forms of mercury;

g. Provide all new components for extraction and titration for each test;

h. Provide an encapsulated environment while extracting chlorides;

i. Provide a factory sealed titration device for each test;

j. Use the extract sampling container as the titration container.

2.6.2 Test Kit for Measuring Chlorides in Abrasives

Provide test kits to be considered for approval. Each proposed test kit shall:

a. Be a completely self-contained test kit with all materials, supplies, tools and instructions to take tests and identify results;

b. Use identifiable, consistent, factory pre-measured test extract solution;

c. Provide for testing equal volumes of abrasive and test solution;

d. Provide for taking direct measurements of the chloride ion in parts per million (PPM), without using conversion charts or tables;

e. Provide all new components for extraction and titration for each test;

f. Provide a factory sealed titration device for each test;

g. Use the extract sampling container as the titration container.

2.7 ABRASIVE MEDIA

The referenced abrasives specifications have been modified to place additional requirements on testing for soluble salts contamination. Other factors such as on-site handling and recycling can allow contamination of abrasives. Successful testing of chlorides in abrasives does not negate the final acceptance testing of steel surfaces.

Interpret MIL-A-22262 to include the meaning that abrasive material contains a maximum one percent by weight of any toxic substance listed in either Table Z-1, Z-2, or Z-3 or OSHA 29 CFR 1910-SUBPART Z, with the exception of inert or nuisance dust materials, arsenic, beryllium, cadmium, cobalt, lead, mercury, rhodium, silver, tellurium, thallium, and uranium.

2.7.1 Non-metallic Abrasive Media

Abrasive media shall conform to MIL-A-22262 , Type I (Inorganic materials)

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a. The maximum allowable chloride content is 7 parts per million (ppm) as measured with the test kit described in article entitled "Test Kit for Measuring Chlorides in Abrasives."

b. The gross gamma radioactivity shall not exceed 5 picocuries per gram.

Use sampling procedures and testing frequencies as prescribed in MIL-A-22262 . Use abrasive media that is specifically selected and graded to provide a sharp, angular profile to the specified depth. Do not use ungraded media. Make adjustments to processes or media gradation to achieve specified surface profile. Do not use recycled non-metallic abrasive media.

2.7.2 Metallic Abrasive Media

Use abrasive media that is specifically selected and graded to provide a sharp, angular profile to the specified depth. Make adjustments to processes, media gradation, or media hardness to achieve specified surface profile.

2.7.2.1 New and Remanufactured Metallic Abrasive Media

Abrasive media shall conform to the chemical and physical properties of SSPC AB 3 , except that:

a. The maximum allowable chloride content is 7 parts per million (ppm) as measured with the test kit described in article entitled "Test Kit for Measuring Chlorides in Abrasives." Modify the requirements of SSPC AB 3 to substitute requirement for one chloride test for each "WATER SOLUBLE CONTAMINANTS" test required.

b. Hardness of steel grit shall be chosen to match requirements of abrasive blasting work.

c. The gross gamma radioactivity shall not exceed 5 picocuries per gram.

2.7.2.2 Recycled Metallic Abrasive Media

Abrasive media shall conform to the chemical and physical properties of SSPC AB 2 except that:

a. The maximum allowable chloride content is 7 parts per million (ppm) as measured with the test kit described in article entitled "Test Kit for Measuring Chlorides in Abrasives." Modify the requirements of SSPC AB 2 to substitute requirement for one chloride test for each "WATER SOLUBLE CONTAMINANTS" test required.

b. The maximum allowable Chromium and Cadmium content of the work mix shall be 0.1 percent by wt. when tested in accordance with ASTM D3718 for Chromium and ASTM D3335 for Cadmium. Modify the requirements of SSPC AB 2 to add requirement for one Chromate test and one Cadmium test for each "LEAD" test required.

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PART 3 EXECUTION

3.1 STRUCTURAL

3.1.1 Fabrication

By mechanics skilled in the trade and in accordance with the manufacturer's directions. Metalwork shall be well formed to shape and size, with sharp lines, angles, and true curves. Work shall be fabricated to allow for expansion and contraction of materials. Provide welding and bracing of adequate strength and durability, with tight, flush joints, dressed smooth and clean. Prior to erection, members shall be identified with a painted erection mark.

3.1.1.1 Measurements

Before fabrication, verify all measurements to ensure coordination of new members to existing tower structure.

3.1.1.2 Metal Surfaces

Shall be clean and free from mill scale, flake rust and rust pitting; well formed and finished to shape and size, with sharp lines, angles, and smooth surfaces. Shearing and punching shall leave clean true lines and surfaces. Weld permanent connections. Welds shall be used and finished flush and smooth on surfaces that will be exposed after installation.

3.1.1.3 Construction

Thickness of metal and details of assembly and supports shall be as indicated. Joints exposed to weather shall be formed to exclude water.

3.1.1.4 Fastening

Provide the necessary brackets so that the work can be assembled in a neat and substantial manner. Holes for bolts and screws shall be drilled.

Joints exposed to the weather shall be formed to exclude water. Conceal fastenings where possible.

3.1.1.5 Shop Fabrication

Fabrication and assembly shall be done in the shop to the greatest extent possible.

3.1.2 Galvanizing

New metal, except stainless steel, shall be galvanized. Galvanize after fabrication. Repair galvanizing damaged by handling, transporting, cutting, welding, or bolting. Do not heat surfaces to which repair paint has been applied. Coat inside of holes drilled in existing steel structure with cold galvanizing repair compound within 1 hour of drilling.

3.1.3 Welding

Perform welding, welding inspection, and corrective welding, in accordance with AWS D1.1/D1.1M for steel. Existing tower steel shall be stripped to bare metal prior to welding. Weld in a manner to prevent permanent distortion of the connected parts. Weld continuously along the entire area of contact. Provide AWS qualified welders, welding operators and

W912HV-25-B-0003 SECTION 09 97 13.25 Page 16 AM-0002 tackers.

3.1.3.1 Exothermic Welding

Use exothermic weld kits for connections of #3/0 AWG bare copper grounding wire.

3.1.4 Connections

Except as modified in this section, connections not detailed shall be designed in accordance with AISC 360 . Build connections into existing work. Punch, subpunch and ream, or drill bolt holes. Bolts, nuts, and washers shall be clean of dirt and rust, and lubricated immediately prior to installation.

3.1.4.1 Bolts

ASTM A325 or JIS B 1186 , Type F8T bolts shall be fully tensioned to 70 percent of their minimum tensile strength. Provide load indicator washers in all high strength bolted connections. Direct tension indicator tightening, or installation of alternate design fasteners, shall be the only acceptable tightening methods. Bolts shall be installed in connection holes and initially brought to a snug tight fit. After the initial tightening procedure, bolts shall then be fully tensioned, progressing from the most rigid part of a connection to the free edges.

3.1.4.2 Installation of Load Indicator Washers (LIW)

ASTM F959/F959M . Where possible, the LIW shall be installed under the bolt head and the nut shall be tightened. If the LIW is installed adjacent to the turned element, provide a flat ASTM F436 washer between the LIW and nut when the nut is turned for tightening, and between the LIW and bolt head when the bolt head is turned for tightening.

3.2 COATING SAMPLING AND FIELD TESTING

3.2.1 Coating Sample Collection

Notify Contracting Officer three days in advance of sampling. The Contracting Officer and either the QC Manager or NACE Coating Inspector shall witness all sampling. Obtain a one liter sample of each batch of each base material, and proportional samples of each activator based on mix ratio, by random selection from sealed containers in accordance with ASTM D3925. Prior to sampling, mix contents of sealed container to ensure uniformity. A batch is defined as that quantity of material processed by the manufacturer at one time and identified by number on the label.

Identify samples by designated name, specification number, batch number, project contract number, sample date, intended use, and quantity involved. Ship samples to an approved laboratory for testing as required by paragraph entitled "Testing of Coating Samples."

3.2.2 Coating Sample Testing

Test samples of all primer, intermediate, and topcoat materials for compliance with requirements of Table I. Reject samples that fail tests, reselect, and retest samples.

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3.3 SURFACES TO BE COATED

Coat all exposed surfaces, including ladders, railings, and other exterior appurtenances.

3.3.1 Protection of Items not to be Painted

Remove or protect all objects not to be abrasive blasted or painted.

Items that are to be removed or protected are listed below:

a. Guys, guy insulators, guy hardware

b. Base insulator

3.4 ACCEPTABLE INSTALLERS

Contractors qualified in accordance with this section shall perform all surface preparation and coating application.

3.5 LIGHTING

Provide lighting for all work areas as prescribed in SSPC Guide 12 .

3.6 SURFACE PREPARATION

3.6.1 Abrasive Blasting Equipment

Use abrasive blasting equipment of conventional air, force-feed, or pressure type. Maintain a minimum pressure of 650 kPa at nozzle. Filter air supply so that air is free of oil and moisture in accordance with ASTM D4285. Test compressed air quality at each startup, but in no case less often than every five operating hours.

3.6.2 Abrasives for Soluble Salts Contamination

Test abrasive media for chloride contamination using test kit as described in article entitled "Test Kit for Measuring Chlorides in Abrasives." The maximum allowable chloride concentration is 7 ppm. Collect composite samples using techniques described in MIL-A-22262 article entitled "QUALITY CONFORMANCE INSPECTION." Test abrasive media immediately prior to use, and in no case more than 24 hours prior to use.

3.6.2.1 Pre-Preparation Testing of Abrasive Media Shipped in Bulk Containers

For bulk containers containing 1350 kg or less, test one composite sample from each container. Reject entire container for non-conforming test.

For bulk containers over 1350 kg, test one composite sample for each 1350 kg, one sample from each compartment, as appropriate. Reject entire container or compartment for non-conforming test.

3.6.2.2 Abrasive Media Shipped in Bags (Nominal 50-110 lb.)

Maintain palletized grouping as provided from supplier. Test composite sample from one bag of each pallet, but no less than one sample each 1350 kg of abrasive. Reject entire pallet for nonconforming test. If palletized grouping is not maintained, sample and test one bag for every 450 kg of abrasive. Reject each 450 kg represented by a nonconforming test. If bags are stamped with Lot number, test composite samples from

W912HV-25-B-0003 SECTION 09 97 13.25 Page 18 AM-0002 each of two bags per lot. Reject entire lot for nonconforming test.

3.6.2.3 Operational Testing of Recycled Metallic Abrasive Media

For batch processing of abrasive, test composite sample of each batch.

Reprocess entire batch for non-conforming test. For continuous processing, test composite sample once per cycle, but no less that one sample every four hours. For non-conforming test during continuous processing, discontinue processing, check equipment for correct operation, and check surfaces prepared with non-conforming abrasive media as prescribed in Article entitled "Pre-Application Testing For Surface Contamination." Make adjustments to equipment or to processing as required to correct problem, and resume blasting when testing indicates that equipment is operating properly.

3.6.3 Clean

Brush-off blast all surfaces in accordance with SSPC 7/NACE No.4 to remove all corrosion products, including surface rust and pack rust. After abrasive blasting, remove abrasive and dust from surfaces by brushing, blowing with dry compressed air, and remove all loose material from vicinity of areas to be painted.

3.6.4 Surface Standard

Inspect surfaces to be coated, and select plate with similar characteristics and surface characteristics for use as a surface standard. Blast clean one or more 300 mm square steel panels. Surface preparation and profile shall be as specified in paragraph entitled "SURFACE PREPARATION." Record blast nozzle type and size, air pressure at nozzle and compressor, distance of nozzle from panel, and angle of blast to establish procedures for blast cleaning. Measure surface profile in accordance with ASTM D4417. Seal surface standard with a clearcoat protectant, or keep wrapped and sealed in vapor-tight material, for use as a standard of comparison for steel surfaces throughout the course of work.

3.6.5 Pre-Preparation Testing for Surface Contamination

Perform testing, abrasive blasting, and testing in the prescribed order.

3.6.5.1 Pre-Preparation Testing for Oil and Grease Contamination

Ensure surfaces are oil-free by visual examination. Check entire structure with water misted onto surface. Any beading of water is indication of oil or grease contamination. Clean contaminated surfaces in accordance with SSPC SP 1 and recheck for contamination until surfaces are grease and oil-free.

3.6.5.2 Pre-Preparation Testing for Soluble Salts Contamination

Test surfaces for soluble salts, and wash as required, prior to abrasive blasting. Soluble salt testing is also required as a final acceptance test of prepared surfaces after abrasive blasting, and successful completion of this phase does not negate that requirement. This phase is recommended since pre-preparation testing and washing are generally more advantageous than attempting to remove soluble salt contamination after abrasive blasting. Effective removal of soluble salts will require removal of any barrier to the steel surface, including rust. This procedure may necessitate the use of wet abrasive blasting, high pressure

W912HV-25-B-0003 SECTION 09 97 13.25 Page 19 AM-0002 water washing, or water washing with a soluble salt remover that is biodegradable, noncorrosive, nontoxic, and leaves no film. Delays between testing and preparation, or testing and coating application, may allow for the formation of new contamination. Use potable water, or potable water modified with soluble salt remover, for all washing or wet abrasive blasting. Test methods and equipment used in this phase are selected at the Contractor's discretion.

3.6.6 Abrasive Blasting

Abrasive blast steel surfaces to near-white metal in accordance with SSPC SP 10/NACE No. 2 . Near-white metal surfaces shall conform to SSPC VIS 1 and shall match the prepared test-panels. Provide a 50 to 75 micron surface profile. Surface profile greater than 75 microns will not be accepted. Measure surface profile in accordance with ASTM D4417. Time interval between abrasive blasting and application of primer shall not exceed eight hours. After abrasive blasting, clean surfaces of dust and debris by brushing, blowing with oil-free and moisture-free compressed air, or vacuuming.

3.6.7 Pre-Application Testing For Surface Contamination

3.6.7.1 Pre-Application Testing for Oil and Grease Contamination

Ensure surfaces are oil-free by visual examination. Check questionable areas and random areas for beading of water misted onto surface. Clean contaminated surfaces in accordance with SSPC SP 1 and recheck for contamination until surfaces are oil-free. Reblast tested and cleaned areas as required.

3.6.7.2 Pre-Application Testing for Soluble Salts Contamination

Test surfaces for chloride contamination using the Test Kit described in article entitled "Test Kit for Measuring Chlorides on Steel Surfaces".

Test all surfaces at rate of three tests for the first 100 square meters plus one test for each additional 300 square meters or part thereof. One or more readings greater than 5 micrograms per square centimeter of chlorides shall be cause for rejection of surface. Wash all surfaces as discussed in article entitled "Pre-Preparation Testing for Soluble Salts Contamination," allow to dry, and re-test until all required tests show allowable results. Reblast tested and cleaned areas as required. Label all test tubes and retain for test verification.

3.6.7.3 Pre-Application Testing for Surface Cleanliness

Apply coatings to dust free surfaces. To test surfaces, apply strip of clear adhesive tape to surface and rub onto surface with finger. When removed, the tape should show little or no dust, blast abrasive, or other contaminant. Clean contaminated surfaces and retest. Test surfaces at rate of three tests for the first 100 square meters plus one test for each additional 300 square meters or part thereof.

3.7 MIXING AND APPLICATION OF COATING SYSTEM

3.7.1 Preparation of Coating Materials for Application

Each of the epoxy and polyurethane products, intermediate, and topcoat, is a two-component coating supplied in separate containers.

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3.7.1.1 Mixing Intermediate and Topcoat Materials

Mix in accordance with manufacturer's instructions, which may differ for each product. Do not mix partial kits or alter mix ratios. Mix all coating materials in same temperature and humidity conditions specified in article entitled "DELIVERY AND STORAGE." Allow epoxy material to stand for required induction time based on its temperature. Keep coating material containers covered at all times after mixing and during application to prevent contamination. The polyurethane coating material is moisture sensitive and any introduction of moisture or water into the material during mixing or application will shorten usable pot life.

3.7.1.2 Pot Life

Apply mixed products within stated pot life for each product. Stop applying when material becomes difficult to apply in a smooth, uniform wet film. Do not add solvent to extend pot life. Add all required solvent at time of mixing. Pot life is based on standard conditions at 21 degrees C and 50 percent relative humidity. For every 10 degrees C rise in temperature, pot life is reduced by approximately half, and for every 10 degrees C drop it is approximately doubled. Other factors such as the shape of the container and volume of mixed material may also affect pot life. Precooling or exterior icing of components for at least 24 hours to a minimum of 10 degrees C in hot climates will extend pot life. High humidity at time of mixing and application shortens pot life of the Polyurethane topcoat material. Following are approximate pot life times at 21 degrees C:

Epoxy materials 4 hours Polyurethane materials 2 hours.

3.7.1.3 Application Conditions and Recoat Windows

The overcoating requirements for the coating system are very time and temperature sensitive. If ambient conditions do not allow for orderly application of primer, stripe coat, intermediate coat and topcoat, use appropriate means of controlling surface temperatures, as required.

Partial or total enclosures may be required, as well as other measures, to control conditions to allow for orderly application of all required coats.

Apply coating only when ambient air and steel temperatures are between 16 and 38 degrees C, and steel surface temperature is more than 3 degrees C above the dew-point of the ambient air during application and the first four hours for epoxy and the first eight hours for polyurethane. Do not apply coatings above 38 degrees C or below 16 degrees C.

Use Table entitled "RECOAT WINDOWS" to determine appropriate recoat windows for each coat after the initial coat. Apply each coating during appropriate RECOAT WINDOW.

If coating is not applied during RECOAT WINDOW, apply during EXTENDED RECOAT WINDOW. Application of any epoxy coat within the EXTENDED RECOAT WINDOW requires application of a TACK COAT prior to applying any full coat. Perform cure test immediately prior to application of TACK COAT to determine condition of applied coating. If CURE TEST indicates that surface is fully cured, provide GLOSS REMOVAL prior to application of TACK

COAT.

If coating is not applied during EXTENDED RECOAT WINDOW, wash surface with

W912HV-25-B-0003 SECTION 09 97 13.25 Page 21 AM-0002 water and detergent, rinse clean with fresh water and allow surface to dry thoroughly, provide GLOSS REMOVAL, apply TACK COAT, where applicable, within 24 hours, and apply next full coat within TACK COAT RECOAT WINDOW.

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RECOAT WINDOWS

EPOXY OVER EPOXY

Temperature degrees C 16-21 22-27 28-32 33-38 39-43 44-49

RECOAT WINDOW (Hrs.) 24-72 18-60 16-48 12-36 8-18 4-6

EXTENDED RECOAT (Hrs.) 72-168 60-140 48-120 36-96 18-36 6-12

TACK COAT RECOAT WINDOW

(Hrs.)

6-72 4-60 4-48 3-36 2-18 1-6

POLYURETHANE OVER EPOXY

Temperature degrees C 16-21 22-27 28-32 33-38 39-43 44-49

RECOAT WINDOW (Hrs.) 24-72 18-60 16-48 12-36 8-18 4-6

RECOAT WINDOW (Hrs.) 24-96 24-72 16-48 12-36 10-24 8-16

EXTENDED RECOAT (Hrs.) 96-168 72-144 48-120 36-96 24-48 16-24

TACK COAT RECOAT WINDOW

(Hrs.)

24-96 24-72 16-48 12-36 10-24 8-16

POLYURETHANE OVER POLYURETHANE

Temperature degrees C 16-21 22-27 28-32 33-38 39-43 44-49

RECOAT WINDOW (Hrs.) 8-48 6-48 4-36 3-24 2-12 1-2

EXTENDED RECOAT (Hrs.) NONE

TACK COAT RECOAT WINDOW

(Hrs.)

NO TACK COAT USED

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The temperature ranges shown in the table above are for determining recoat windows. Choose recoat window based on the highest surface temperature that was sustained for one or more hours between coats. This applies to the entire time between coats. Measure and record air and surface temperatures on hourly basis to determine appropriate recoat windows. If surface temperature goes above 38 degrees C, measure and record temperatures every half hour.

CURE TEST - Where indicated, test surface for cure using high-flash aromatic Naphtha only (cas #64742-95-6). Do not use aliphatic VMP Naphtha. Wipe surface with rag saturated with Naphtha, and check for surface tackiness, loss of gloss, or other indications that solvent has softened surface. If softening is found on 95 percent of test sites, this is indication that coating has not fully cured, and GLOSS REMOVAL is not required if TACK COAT is applied within three hours and full coat is applied within the TACK COAT RECOAT WINDOW. Test surfaces at rate of three tests for the first 100 square meters plus one test for each additional 300 square meters or part thereof.

TACK COAT - Where indicated, apply coat of intermediate coat epoxy, at 25 to 50 microns WFT, then apply next specified full coat within TACK COAT RECOAT WINDOW. Thin TACK COAT material approximately 25 percent by volume, using appropriate epoxy thinner.

GLOSS REMOVAL - Where indicated, remove all gloss by brush-off abrasive blasting in accordance with SSPC 7/NACE No.4 or by hand sanding with 150-200 grit wet/dry sandpaper, pressure wash or wipe down with a clean rag soaked with denatured alcohol to remove dust. If zinc primer coat is brush-off abrasive blasted, touch-up or overcoat as required to restore zinc coating to 100 percent coverage of steel surfaces, to the specified primer coat thickness.

3.7.2 Application of Coating System

Apply coatings in accordance with SSPC PA 1 and as specified herein.

Apply coatings to surfaces that meet all stated surface preparation requirements.

After application of primer coat and prior to application of each subsequent coat, perform testing prescribed in article entitled "Pre-Application Testing For Surface Contamination," as necessary, to ensure minimal intercoat contamination. This testing may be reduced to one half of the prescribed rate for bare steel if the testing indicates no contamination when sampling is evenly distributed over surfaces being tested. If contamination is found between coats, revert to the specified testing rate. Generally, oil and grease contamination and soluble salts contamination are not encountered if subsequent coats are applied within specified recoat windows and unusual atmospheric events do not occur.

Such atmospheric events as a coastal storm blowing onshore can bring unusual chloride contamination. Concern for intercoat contamination should be continually prevalent, and spot testing should be accomplished to verify satisfactory conditions. Where visual examination or spot testing indicates contamination, perform sufficient testing to verify non-contamination, or to define extent of contamination for appropriate treatment.

Apply each coat in a consistent wet film, at 90 degrees to previous coat.

Ensure that primer and intermediate coat "cold joints" are no less than

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150 mm from welds. Apply stripe coat by brush. Apply all other coats by spray application. Use appropriate controls to prevent airborne coating fog from drifting beyond three meters from the structure perimeter. Cover or protect all surfaces that will not be coated. The cleanliness, temperature, recoat windows, and airborne paint containment requirements may necessitate the use of enclosures, portable shelters, or other appropriate controls.

3.7.2.1 Application of Intermediate Coat

Apply intermediate coat within RECOAT WINDOW of primer coat. Apply intermediate coat 75 to 125 microns DFT. Check coating thickness prior to application of topcoat. If additional coating film is required, use intermediate coating material to provide desired thickness, then apply topcoat.

3.7.2.2 Application of Topcoat

Make all required repairs to primer and intermediate coats as specified in paragraph entitled "Procedure for Making Spot Repairs" prior to applying topcoat. Apply topcoat within RECOAT WINDOW of intermediate coat. Apply polyurethane topcoat 40 to 60 microns DFT. Total system of primer, intermediate, and topcoat shall not be less than 225 microns DFT. Apply additional topcoat, if necessary, to obtain required minimum total system thickness.

3.7.2.3 Procedure for Making Spot Repairs

Use this procedure only with written approval from the Contracting Officer. Observe all requirements for soluble salts contamination and cleanliness between coats. Apply each coat within RECOAT WINDOW of preceeding coat.