825.03 CONSTRUCTION METHODS 825.03.1 NEW STEEL STRUCTURES

Work under this Section shall be in accordance with Subsection 825.03.1 of the Standard Specifications except as modified below.

Work under this Section shall include, but is not limited to, all new structural steel specified to be shop primed and field primer touch-up and field intermediate and field finish topcoat painted as described in Section 825.01 of this Special Provision and to the limits shown on the Plans or as directed by the Engineer. Work under this Section shall also include field touch-up of intermediate and finish coats, as required. Work on new steel that is required to complete repairs shall be painted as part of 825.03.2 Existing Steel Structures.

Shop drawings for new steel shall indicate areas of painting to be shop- and field-applied. Cleaning, surface preparation, and painting shall be performed as follows for all new steel surfaces specified to be shop painted:

a) Cleaning: Delete Subsection 825.03.1(a) of the Standard Specifications in its entirety and replace with the following:

Areas in which oil and/or grease are present shall be cleaned by solvent cleaning methods as described in the Society for Protective Coatings Surface Preparation Specification No.1; Solvent Cleaning (SSPC-SP1). This cleaning shall be performed prior to blast cleaning. If contamination remains after blast cleaning, the surfaces shall be recleaned with the SSPC-SP1 procedures.

b) Surface Preparation: Delete Subsection 825.03.1(b) of the Standard Specifications in its entirety and replace with the following:

Surface preparation shall be in accordance with the SSPC Specifications and any additional requirements contained within this Special Provision.

All steel shall be blast cleaned to a near white condition using the cleaning methods described in the SSPC Surface Preparation Specification No.10; Near White Blast Cleaning (SSPC-SP10).

Unless otherwise allowed by the Engineer, final surface preparation, which exposes the substrate, shall not be performed when the surface temperature is less than 5o F greater than the dew point temperature of the surrounding air.

The surface area of the steel to be blast cleaned shall be no greater than the surface area of steel that can be prime coated in the same day. The maximum time lapse between surface preparation and application of the prime coat shall not be greater than 8 hours. Should any "rust back" occur prior to the application of the prime coat, the surfaces shall be recleaned to the near white condition. The blast cleaning shall leave a 1.5 to 2.5 mil deep, angular, anchor profile in a dense uniform pattern of depressions and ridges. Steel shot shall not be used for cleaning unless it is blended with steel grit to create a sharp, angular profile.

Flame cut edges shall be ground before blast cleaning to assist in attaining the required anchor profile. All reamed or drilled holes in the steel shall have their edges cleaned by methods specified in SSPC-SP1 and softened by grinding prior to blast cleaning. If any grinding occurs after blast cleaning, the profile shall be restored. All fins, tears, slivers and burred or sharp edges present before or after blast cleaning shall be removed by grinding followed by reblasting to attain the required anchor profile.

The near white blast condition may be determined and/or verified by the use of the SSPC pictorial standard guide VIS-1. The surface profile depth shall be measured and/or verified by the use of Testex Replica Tape.

Compressed air supply lines shall be equipped with oil traps and moisture separators. The traps and separators shall be cleaned and/or changed on a regular basis. Cleanliness of the compressed air from each compressor system used for abrasive blast cleaning or blowing down the surfaces shall be verified each work day in accordance with ASTM D4285, Standard Test Method for Indicating Oil or Water in Compressed Air.

All abrasive and deleterious material residues shall be removed from steel surfaces by vacuuming with a commercial grade vacuum cleaner or by double blowing with clean, dry, compressed air. Air blow-down shall be followed by vacuum cleaning of the top surfaces of all flanges, stiffeners, splice plates, hangers, etc. The steel shall then be kept dust free until the coating is applied.

Care shall be taken to protect freshly coated surfaces from subsequent blast cleaning operations. Previously primed surfaces damaged by subsequent blasting operations shall be returned to the near white condition by reblasting, or upon approval of the Engineer, power tool cleaning in accordance with SSPC-SP11, Power Tool Cleaning to Bare Metal. The surfaces shall then be vacuumed and reprimed.

The painting contractor/subcontractor shall provide access to any location where cleaning and painting may be in progress for servicemen, manufacturer's representatives, Authority representatives or other duly authorized persons.

The contractor/subcontractor is required to perform all Quality Control functions to assure that surface preparation and painting meet the requirements of this Special Provision and the Standard Specifications, and provide the results of all inspections and testing in a written daily inspection report. The Engineer will provide Quality Assurance observations. The Engineer's Quality Assurance acceptance of the preparation of all surfaces to be painted is required before any paint is applied. No paint shall be applied to any surface until the Engineer or his representative has accepted the cleanliness and surface preparation of the surfaces to be painted.

c) Painting: The painting of new steel shall be performed in accordance with the applicable requirements of Paragraph c of Subsection 825.03.1 of the Standard Specifications, Subsection 825.03.2(a)3 of this Special Provision, which shall override conflicting requirements, and the following:

Paint film thickness measurements will be made during wet film application, utilizing an approved wet film thickness gauge. Dry film thickness of each coat shall be measured with an approved Type 2 electronic dry film thickness gage meeting the requirements of SSPC-PA2. Measurements for all coats shall be in accordance with SSPC-PA2, except that one hundred percent of all thickness measurements shall be within the specified minimum dry film thickness. Thicknesses as measured by spot readings that are less than one hundred percent of the required thickness shall be cause for rejection. Where thickness measurements fall below the specified minimum, additional applications of paint shall be made as necessary to meet the thickness required, at no additional cost to the Authority. Excessive thickness shall be removed and replaced unless otherwise directed by the Engineer.

The prime coat on new steel shall be shop applied. The intermediate and topcoat shall be field applied. Before the application of the primer touch up, intermediate, or topcoat in the field, all zinc salts, oil, dust, dirt, and other contaminants shall be removed from the steel or previously shop painted surfaces to be painted. Primed surfaces shall be cleaned by pressurized water washing (800 psi min.). Areas in which the shop coating is damaged or is corroded shall be power tool cleaned in accordance with SSPC-SP11 and touched up prior to the application of the intermediate and topcoats.

Areas of new steel where field welding will be performed shall be masked before shop priming.