The American model: AMPP standards and ASTM methods
American practice is organised differently from the ISO 12944 series: coating requirements are assembled in the client’s specification, which refers to two groups of documents. The first is the standards of the industry association AMPP on surface preparation, thickness control and the qualification of contractors and inspectors. The second is ASTM test methods: how to measure profile, thickness, adhesion and continuity. American designations appear constantly in technical data sheets and in the specifications of international contractors working in Central Asia, so it helps to be able to read them without translating them into “ISO language”.
AMPP: NACE and SSPC combined
AMPP (Association for Materials Protection and Performance) was formed in 2021 by the merger of NACE International and SSPC (The Society for Protective Coatings). Since June 2021 their standards programmes have been merged into a single AMPP programme. Published NACE and SSPC documents have kept their alphanumeric designations: when a document is revised, its date changes but the designation stays the same. That is why specifications contain dual numbers such as SSPC-SP 10/NACE No. 2 — this is one joint document of the two former organisations, not two different requirements.
Steel surface preparation: SSPC-SP and NACE
| Designation | Title | What it means |
|---|---|---|
| SSPC-SP 1 | Solvent Cleaning | Removal of oil, grease and other soluble contaminants with solvents |
| SSPC-SP 2, SSPC-SP 3 | Hand Tool Cleaning; Power Tool Cleaning | Hand and power tool cleaning |
| SSPC-SP 11, SSPC-SP 15 | Power Tool Cleaning to Bare Metal; Commercial Grade Power Tool Cleaning | Power tool cleaning to bare metal |
| SSPC-SP 5/NACE No. 1 | White Metal Blast Cleaning | Blast cleaning to “white” metal |
| SSPC-SP 10/NACE No. 2 | Near-White Metal Blast Cleaning | Blast cleaning to “near-white” metal |
| SSPC-SP 6/NACE No. 3 | Commercial Blast Cleaning | “Commercial” blast cleaning |
| SSPC-SP 14/NACE No. 8 | Industrial Blast Cleaning | “Industrial” blast cleaning |
| SSPC-SP 7/NACE No. 4 | Brush-Off Blast Cleaning | Light (brush-off) blast cleaning |
| NACE WJ-1 … WJ-4/SSPC-SP WJ-1 … WJ-4 | Waterjet Cleaning of Metals: Clean to Bare Substrate, Very Thorough, Thorough, Light Cleaning | Four grades of waterjet cleaning |
The blast cleaning grades differ in how much residual mill scale, rust, old coating and staining is allowed to remain on the surface. For visual assessment, AMPP publishes reference photographs: SSPC-VIS 1 for dry abrasive blast cleaning and SSPC-VIS 4/NACE VIS 7 for waterjetting, where the photographs are also used to assess the initial condition of the surface.
We have not found an official correspondence table between SSPC-SP grades and ISO 8501-1 in AMPP documents. Projects often compare them, but the wording and criteria of the standards differ. If a specification refers to both systems, it is better to state explicitly which one governs and to agree any substitution of one designation for another with the client.
Coating thickness: SSPC-PA 2 and ASTM D7091
SSPC-PA 2 (Procedure for Determining Conformance to Dry Coating Thickness Requirements) is one of the documents most often cited in specifications for the frequency and acceptability of dry film thickness measurements. The measurement frequency depends on the size of the coated area, steel beams and test panels are treated separately, and results are assessed against coating thickness restriction levels. The gauges themselves and how to use them are covered by ASTM D7091-22: magnetic and eddy-current gauges and verification of their accuracy. For coatings on concrete, wood and plastics, ultrasonic gauges are used to ASTM D6132-13(2022); the destructive cross-sectioning method with a microscope follows ASTM D4138-07a(2022), and wet film thickness with notch gauges ASTM D4414-25.
ASTM test methods
| What is checked | Standard | Explanation |
|---|---|---|
| Profile after blast cleaning | ASTM D4417-21 | Methods for measuring the profile in the field, shop and laboratory; one of the methods is also suitable for profiles produced by power tools. It replaced ASTM D7127, withdrawn in 2021 |
| Compressed air | ASTM D4285-24 | Presence of oil and water in compressed air for blast cleaning and painting |
| Abrasive cleanliness | ASTM D4940-25 | Water-soluble ionic contamination of abrasives by conductivity |
| Pull-off adhesion | ASTM D4541-22; on concrete — ASTM D7234-22 | Portable adhesion testers; testing to fracture or pass/fail |
| Adhesion by cutting | ASTM D3359-23, ASTM D6677-18(2022) | Tape test with two methods — for systems thicker and thinner than 125 µm; knife test |
| Continuity | ASTM D5162-24; on concrete — ASTM D4787-24 | On metal: low-voltage wet sponge or high-voltage spark testing; on concrete: high-voltage spark testing |
| Cure | ASTM D4752-20(2024), ASTM D5402-19(2024) | Solvent rub: MEK for ethyl silicate zinc-rich primers, a separate practice for organic coatings |
| Air humidity | ASTM E337-15(2023) | Psychrometer: dry-bulb and wet-bulb temperatures |
| Laboratory testing | ASTM B117-26a, ASTM D5894-21 | Salt spray; cycles of salt fog/dry and UV/condensation |
| Condition assessment | ASTM D610-25, ASTM D714-25 | Degree of rusting of painted steel and degree of blistering |
ASTM reissues its standards regularly, and the year after the hyphen is part of the designation. The table shows the editions current as of October 2026; older specifications cite earlier ones.
Concrete
The preparation of concrete for coating is described in SSPC-SP 13/NACE No. 6 (Surface Preparation of Concrete). ASTM methods cover surface cleaning of concrete before coating (D4258-23), preparation by abrasion to create a profile and remove weak laitance (D4259-24), testing for capillary moisture by the plastic sheet method (D4263-24) and relative humidity in floor slabs with in-situ probes (F2170-19a), as well as pull-off adhesion (D7234-22) and the continuity of linings on concrete (D4787-24). The chemical resistance of coatings on concrete is not chosen from general tables — for that we use our questionnaire.
Qualification of contractors and inspectors
- AMPP QP 1 and QP 3 (formerly SSPC QP programmes) — accreditation of painting contractors: QP 1 for field application on complex industrial and marine structures, QP 3 for shop painting.
- NACE No. 13/SSPC-ACS-1 — qualification and certification of industrial coating and lining application specialists.
- AMPP Coatings Inspector Program (CIP) — three levels: Basic Coatings Inspector (CIP Level 1), Certified Coatings Inspector (CIP Level 2) and Senior Certified Coatings Inspector (CIP Level 3). According to AMPP, it will eventually take the place of the former NACE CIP and SSPC PCI programmes in standards and requirements.
- ASTM D3276-21 — a guide for painting inspectors on metal substrates.
Separate AMPP documents deal with the design of tanks and vessels to be lined (NACE SP0178) and with corrosion under thermal insulation (SP0198) — see the pages on tank coatings and oil and gas facilities.
Applicability in Uzbekistan
Under the Law “On Standardization”, standards of foreign countries apply in Uzbekistan on a par with national ones only on the basis of a decision by the national standardization body; without such a decision, American standards become requirements through the contract and the specification. When working with them, check the year of the edition, the units (some values in the standards are originally given in mils) and that a specification based on American standards does not contradict the national codes — see Corrosion protection standards in Uzbekistan. The texts of the standards are distributed by AMPP and ASTM themselves: a reference is enough in the design documentation, but it is worth obtaining a working copy for the site from the publisher.
Is the specification for your facility written to SSPC and ASTM? We will compare its requirements with ISO and Uzbek codes and select the system and inspection procedure. Phone, WhatsApp, Telegram: +998 94 094 52 27. E-mail: info@ognezashita.uz.