Handy Table on Surface Contamination

NAVY SEA Systems Command
Materials Engineering Group
Codes SEA 03M12.5
2531 Jefferson Davis Highway
Arlington, VA 22242-5160

Soluble Substances Table 1  (P & W Hand Held Hydroblast Unit)
  Total Sample Area  (cm2) 112.5
 Total µg/ cm2   2.61
 Chloride µg/ cm2  0.85

Soluble Substances Table 2 (ABB Hand Held Grit Blast Unit)
 Total Sample  Area (cm2) 50
 Total µg/ cm2   120.71
 Chloride  µg/ cm2  62.55

How is this going to be spent?

A few days ago we decided that we needed to take some action on the new budget.

The government is going to need a lot of help if it is to know how to spend some of the following:

$6 Billion on energy efficiency in public housing.
$5 Billion on weatherization grants to homeowners.
$8 Billion on public transit and ancillary infrastructure.
$40 Billion assisting school districts to modernize.
$2 Billion rehabing foreclosed properties.
$29 Billion for roads and bridges.

Personally, I don’t think we should have very much faith in the decision process. We’ll tend to get storm windows on houses in Lake Charles, La. and screens on houses in Montana. New benches at bus stops will feature eye catching designs and no shelter roofs. Old-but-serviceable will become targets for new-and-novel. The public will get a whole slew of new buzz words and politicians won’t have to get colds kissing babies for a while. Dedicating a few new acres of asphalt is safer than repainting the food bank.

Inspection Manual for Flash Rust

Inspection Manual for Flash RustSupplement to Standard Photograph Guides
Supplement to VIS-4

December 29, 2008

Prepared for
Advanced Technology Institute
SSA: No. 2008-326

Prepared by
Lydia M. Frenzel, Ph.D.
Fat Squirrel 22, LLC
On behalf of
Project Participants:
Todd Pacific Shipyard- Lead Shipyard

Project Goals and Objective:

This document is a supplement to SSPC-VIS No. 4 NACE VIS 7 (or ISO 8501-4).

SSPC-VIS No. 4 NACE VIS 7, ISO 8501-4, International Paint Hydroblasting photos, and Hempel photos do not illustrate: 1. an example of lightly wiping; 2. an example of the surface after excess flash rust with loose rust dust has been mitigated by pressure washing.

For this manual, “Flash Rust” is the rust that occurs from the time the waterjet (WJ) or wet abrasive blast (WAB) cleaning process starts to the time the water used for the cleaning process dries. Flash rust often looks like a rust bloom.

Look at SSPC-VIS No. 4 NACE VIS 7, ISO 8501-4, and NACE No. 5- SSPC- SP-12 for a more detailed definition of flash rust.

“Rust-Back” is used in dry abrasive blast standards. Rust-Back occurs on surfaces that appear to be dry. Rust Back is the rust that occurs when DRY, bare steel is exposed to conditions of high humidity, moisture, or a corrosive atmosphere.

“Rust Bloom” is somewhat uniform rust spread evenly over a large section of the surface. Rust Bloom is a generic description. The observer doesn’t know if it originates from flash rust or rust-back.

Coatings manufacturers will designation the level of Flash Rust that is acceptable for the coating in a specific environment.

How much “Flash Rust” is formed is directly related to time of wetness. Engineering controls and project scheduling are key in reducing the time of wetness. Look at Blast and Dry, Clean Blasting, and Drying Effects.mpg

Inspecting for “Flash rust” is not rocket science.
It is deceptively simple or deceptively hard, because the decision is subjective.
? Prior to painting, look at the rust bloom on the steel.
? Find out the environmental history-if there was rain, pressure washing, waterjet cleaning, or no water involved at all.
? If there is no water involved, you reject the “Rust-Back.”
? If there is water involved in the surface cleaning, you place VIS-4 up to the surface nest to the rust and make an initial judgment concerning light, moderate, and heavy.
? If necessary, you wipe the “Flash Rust” to continue the determination between light, moderate, and heavy.
? Be consistent in the determination methods.
? Mitigate the flash rust to the amount required by the project specifications.

This manual does not address whether or not the amount of flash rust is suitable for coatings. Coatings manufacturers DO NOT recommend painting over HEAVY flash rust. The coatings must wet to the substrate, consolidate the dust, and be thick enough to cover the rust dust.

SSPC, NACE, ISO and Coatings Manufacturers published several guides to “Flash Rust” with photos.
All guides are to be used in the same manner. All lead to the same answer!

Download this manual here:

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