PROGRAMMING MAINTENANCE PAINTING

12.1 Definitions of Programmed Painting and Maintenance Painting. Paint programming is a systematic planning process for establishing when painting is required, what painting should be done, by whom, at what times, and in what manner. Maintenance painting is a vital adjunct to programmed painting. It is defined as a field procedure for maintaining existing coatings in an acceptable condition.

12.2 Components of Programmed Painting. There are three

basic components of successful paint-programming plans: plans

for initial design of the facility, plans for monitoring conditions of structures and coating systems, and plans for maintenance painting. Each plan must be prepared properly and completely for the total program to be successful.

Programmed painting can best be implemented as a computer program. This program will contain the initial design data, data on the conditions of the structures and their coating systems obtained from an annual inspection report, and recommended maintenance painting schedules and procedures. The latter should include cost estimates for each item of work so that funding can be requested well in advance of the time it will be spent. Cost estimating programs for construction work are available in the Construction Criteria Base (CCB) (National Institute of Building Sciences, Washington, DC) and proprietary sources.

12.2.1 Initial Design. The design of both new structures and their coating systems is critical to achieving maximum life of each.

12.2.1.1 Structural Design. Structures should be designed so that they are easy to coat initially and to maintain in an acceptable condition. Common structural design defects include:

a) Contact of Dissimilar Metals. The more active metal will rapidly be consumed by galvanic corrosion to protect the less active metal. This includes contact of steel and stainless steel.

b) Water Traps. Structural components that collect rainwater corrode more rapidly. These components should either be turned upside down or have weep holes of sufficient size and correct placement drilled in them. Weep holes should be as large as possible and placed at the bottom of the structure.

c) Configurations That Permit Vapors or Liquids to Impinge on Structural Components. Structures such as steam lines.

d) Configurations Restricting Access. Structures that restrict access for painting receive poor quality maintenance.

e) Designs Creating Crevices. Crevices are difficult to coat, and the oxygen deficiencies in them produce a type of galvanic corrosion.

f) Other Difficult to Paint Surfaces. Sharp edges and welds should be ground, pits should be filled, and corners should be avoided.

12.2.1.2 Design of Coating System. The original coating system must be designed to be compatible with both the environment in which it is to be located and the substrate to which it is to be applied. Sections 4 and 5 of this handbook list systems that meet this requirement and are cost effective. As far as possible, it is desirable to specify coating systems that are easy to apply and maintain. It is always preferable to do the surface preparation and the paint application in the controlled environment of a shop as compared to the field. If this is not possible, this work should be accomplished at the work site before rather than after erection.

12.2.2 Plan for Monitoring Conditions of Structures and Their Protective Coatings. Annually, each coated structure at each military activity should be inspected for deterioration of both the substrates and their coatings. Both the types and the extent of deterioration should be noted, and the generic type of the finish coat should be determined if it not already known. An estimate should also be made as to when structural and coating repairs should be made to prevent more serious damage. Other structures at the activity that require the same type of maintenance should also be noted, since it would be more economical to include as many structures as appropriate in a single contract. An example of an inspection form which has been successfully used for routine inspections and could be modified to meet an installation’s needs is shown in Figure 26.

12.2.2.1 Determining the Type of Coating Failure. The type of coating failure can be determined by following the procedure given in Section 11.

12.2.2.2 Determining the Extent of Coating Failure. In maintenance painting, it is necessary to determine the extent of coating failure to permit realistic bidding for the repair work.

To do this, both the severity of the deterioration and its distribution must be defined. The level of severity will indicate whether only the finish coat or other coats are involved in the deterioration and how it can best be repaired. If the distribution is limited, spot repairing is likely to be practical; if it is extensive, it is probably best to remove all the coating and repaint.

Standard block diagrams for estimating coating deterioration on ships for "Overall Extent" and "Extent Within Affected Areas" are generally also appropriate for shore structures. They are described in ASTM F 1130. First, draw an imaginary line enclosing all deterioration and select the standard "Overall Extent" diagram that best matches the imaginary area. Then, select the standard "Extent Within Affected Area" diagram that best matches the areas within the imaginary line.

The number and letter of the selected diagrams establish the extent of deterioration. Whatever system is used to determine the extent of deterioration, it should utilize a standard format so that evaluations of different structures can be compared and priorities can be established.

It is also important in maintenance painting to determine precisely the amount of loose and peeling paint to establish the amount of work to be done. This will eliminate any controversy over a "site variation," i. e., the contractor claiming that there was much more work necessary than described in the specification. It is a standard practice to define "loose and peeling paint" as that paint that is easily removed with a dull putty knife.

12.2.2.3 Determining the Generic Type of the Finish Coat. Once a painting program is set up, the identifications of paints being applied will automatically be entered into the database. If the generic type of the finish coat is not known, it can be determined by infrared spectrophotometric analysis as described in Section 11. The general compatibility of a coating can be determined by the solvent rub test, also described in Section 11.

12.2.3 Types of Maintenance Painting. In planning maintenance painting, it is first necessary to determine the general scope of the work. There are four different approaches to maintaining an existing coating in an acceptable condition:

a) Cleaning only to restore to an acceptable condition. This may be accomplished by pressure washing or steam cleaning.

Structure Number

Date

Reason for Inspection Inspector’s Name

Substrate:

Component:

Wood

Siding

Aluminum

Window Frame

Concrete

Door

Transite

Door Pocket

Steel

Door Frame

Galvanized Steel

Eaves

Other

Other

Appearance:

Deterioration:

Chalking

Cracking

Fading

Blistering

Mildew

Peeling

Other

Other

MEK Rub Test:

Evaluation (1=good, 4=bad):

– (no effect)

1

+

2

+ +

3

+++ (large effect)

4

Suspected Binder Type:

Samples Collected:

Alkyd

Chip Sample

Latex

Photograph

Epoxy

Factory Finish

Other

Figure 26

Coating Condition and Identification Form

b) Spot repair (priming and topcoating) of areas with localized damage but otherwise sound paint. This should be done before the damage becomes more extensive.

c) Localized spot repair plus complete refinishing with topcoat only. This should be done when localized repair only would produce an unacceptable patchy finish.

d) Complete removal of existing paint and total repainting. This should be done when the damage is so extensive that types "b" or "c" are impractical or uneconomical.

Repair of exterior coatings may not be warranted with the first appearance of weathering, but deterioration should not proceed to the point that damage occurs to the substrate, or more costly surface preparation or application techniques become necessary. If lead-containing paint is present, the costs for paint repair or removal will be much more expensive. If the paint can be maintained in place, a great deal of savings will result. New restrictions on abrasive blasting and other surface preparation techniques may also significantly increase total costs. Thus, scheduling of repairs should be made to avoid such costly operations.

12.2.4 Plan for Maintenance Painting. The plan for maintenance painting includes selection of the surface preparation, application, and inspection methods and the materials to be used.

12.2.4.1 Selecting Materials for Maintenance Painting. For localized repairs to an otherwise sound coating system (12.2.3 types "b" and "c"), it is wise to repair a damaged coating system with the same coating previously used or one of the same generic type or curing mechanism to avoid incompatibility. If in doubt as to the compatibility of a paint to be applied to an existing finish, apply a small patch to it and inspect it after 2 to 3 days for any bleeding, disbanding, or other sign of incompatibility.

For total recoating (12.2.3 type "d"), select the coating as described for new work in Section 4 or 5.

12.2.4.2 Surface Preparation for Maintenance Painting. For making localized repairs, it is best to use the surface preparation methods for different substrates described in Section 6. It may be more practical or necessary, however, to use hand or power tools rather than abrasive blasting where the amount of work to be done is small, or where abrasive blasting would contaminate an area.

Loose and peeling coating should be removed, and the adjacent intact coating should be sanded to produce a feathered edge and roughened paint surface extending 2 inches beyond the repair area. The feathered edge will produce a smoother transition between the old and new paint and roughening the adjacent intact paint will permit good adhesion of the new primer.

Feather edging of steel may be accomplished by blasting with a fine abrasive (e. g., 60 mesh grit or finer) with the nozzle held at a low angle about 3 or 4 feet from the surface. However, even fine abrasive may damage adjacent coating. Thus, it is best to determine if there are any adverse effects with a surface preparation procedure before proceeding will it.

12.2.4.3 Application for Maintenance Painting. Spot application of paint in maintenance painting is usually done by brush or spray, as the painter determines to be most efficient. Brushing of the primer is usually preferred where the surface is rough or otherwise difficult to paint. Patches should be extended 2 inches beyond the areas of damaged coatings where the adjacent intact paint has been previously roughened.

12.2.4.4 Inspection of Maintenance Painting. Inspection of maintenance painting usually consists of visual inspection for workmanship, dry film thickness, and adhesion. Fuel tanks and lines, waterfront structures, and other critical structures should also be tested for holidays Imperfections in the coating). These inspection procedures are described in Section 9.

12.2.5 Scheduling the Work. By planning work well in advance, it is possible to schedule it at a time when minimum inclement weather is expected. It may also be possible to schedule it when there will be less interference with other trades doing construction work or personnel utilizing the structures.

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