Concrete surface profile (CSP) is the roughness of prepared concrete, graded from CSP 1 (nearly flat) to CSP 10 (very rough) against the ten reference chips of ICRI 310.2R-2013. The data sheet of the coating, overlay or repair product sets the CSP range that product needs, and the specifier copies that range into the specification.
The summary table below lists the documents and checks that govern concrete surface profile on a project.
| Attribute | Value |
|---|---|
| Guideline | ICRI 310.2R-2013, CSP 1 to 10 (the 1997 edition had nine profiles) |
| Measurement | ICRI chips (visual and tactile); ASTM D8271-26 (depth micrometer); ASTM D7682-17(2022) (replica putty) |
| Number of locations | AMPP SP21513-2021 |
| Acceptance | CSP range on the product data sheet |
| Verification | Pull-off trial, for example FDOT Dev403EO (rev 2020-08-11) |
| Worker safety (US) | OSHA 29 CFR 1926.1153, respirable crystalline silica |
| Companion checks | Moisture (ASTM F2170-19a, F1869-23); pH after etching or chemical cleaning (ASTM D4262-05(2024)) |
Standards, codes and regulations are checked against their issuing bodies, product values against the named data sheet and prices against the dated source named in the sentence; see our methodology and fact-checking.
What Is Concrete Surface Profile (CSP)?#
ICRI CSP is a ten-step scale of concrete surface roughness defined in ICRI 310.2R-2013, which replaced the nine-step 1997 edition and added CSP 10 for concrete repair. The full title of the guideline is "Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays, and Concrete Repair".
ICRI 310.2R-2013 sets four steps for the specifier: evaluate the substrate, material and job-site conditions; review the preparation methods; select a method; and specify a CSP range together with the quality-control tests.
The ICRI CSP 1 to 10 scale and chips#
Each ICRI chip is a molded replica of about 89 x 114 mm (3.5 x 4.5 in), made with one named preparation method. The methods run from acid etching for CSP 1 to a handheld breaker followed by abrasive blasting or high-pressure water jetting for CSP 10.
KTA-Tator measured the ICRI chips by ASTM D8271 as the mean of 15 readings, and the results show two overlaps: CSP 1 and CSP 2 both measure 152 ± 51 µm (6 ± 2 mils), and CSP 4 and CSP 5 measure 381 ± 51 µm (15 ± 2 mils) and 406 ± 51 µm (16 ± 2 mils). CSP 8 to 10 were not measured.
The concrete surface profile chart below lists the method behind each ICRI chip and its measured depth.
| CSP | ICRI chip made by | Measured depth of the ICRI chip (ASTM D8271, mean of 15 readings, KTA) |
|---|---|---|
| CSP 1 | Acid etching | 152 ± 51 µm (6 ± 2 mils) |
| CSP 2 | Grinding | 152 ± 51 µm (6 ± 2 mils) |
| CSP 3 | Light shotblast | 279 ± 51 µm (11 ± 2 mils) |
| CSP 4 | Light scarification | 381 ± 51 µm (15 ± 2 mils) |
| CSP 5 | Medium shotblast | 406 ± 51 µm (16 ± 2 mils) |
| CSP 6 | Medium scarification | 940 ± 102 µm (37 ± 4 mils) |
| CSP 7 | Heavy abrasive blast | 1,219 ± 102 µm (48 ± 4 mils) |
| CSP 8 | Scabbling | Not measured |
| CSP 9 | Heavy scarification (rotomilled) | Not measured |
| CSP 10 | Handheld concrete breaker, then abrasive blasting or high-pressure water jetting | Not measured |
Chip depths describe the ICRI chips, not a required depth.
ICRI 310.1R, 310.2R and 310.3R: which concrete repair and coating guideline applies?#
Three ICRI guidelines govern concrete preparation: 310.1R-2008 for repair of corrosion-damaged concrete, 310.2R-2013 for selecting and specifying preparation by CSP, and 310.3R-2014 for hydrodemolition. ICRI 310.1R-2008 is titled "Guideline for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion", and repair practice under it clears about 19 mm (3/4 in) of concrete around the full circumference of a corroded bar before patching with concrete repair products.
ICRI 310.3R-2014 is titled "Guideline for the Preparation of Concrete Surfaces for Repair Using Hydrodemolition Methods". ICRI Committee 310 has set itself a 2025 to 2026 goal to revise 310.1, 310.2 and 310.3, so a specification names the edition it cites.
How Is Concrete Surface Profile Measured?#
Concrete surface profile is measured in three ways: visually against ICRI chips, by depth micrometer under ASTM D8271-26, and by replica putty under ASTM D7682-17(2022); only the last two give a number in µm (mils). The table below compares the three methods and the document that sets the number of locations.
| Method | Standard and edition | Equipment | Readings | Result |
|---|---|---|---|---|
| Chip comparison | ICRI 310.2R-2013 | 10 chips, about 89 x 114 mm (3.5 x 4.5 in) | Visual and tactile match | CSP number |
| Depth micrometer | ASTM D8271-26 | Spring-loaded probe, 25.4 mm (1 in) base | At least 15 in a 152 x 152 mm (6 x 6 in) area, outliers discarded | Range and mean in µm (mils) |
| Replica putty | ASTM D7682-17(2022), Method B | Two-component epoxy putty, 38.1 mm (1.5 in) impression, micrometer | 10 | Difference between lowest and highest peak-to-valley reading |
| Number of locations | AMPP SP21513-2021 | Applies to all three methods | Set per method | Conformance to the specified profile |
Visual comparison with ICRI CSP chips#
Chip comparison is visual and tactile: the inspector holds the chips against the prepared surface and records the CSP number that matches. The comparator must be named in the record, because licensed replica samples of about 58 cm² (9 in²), cast from 48 MPa (7,000 psi) concrete, measure differently from the ICRI chips. By ASTM D8271 the licensed CSP 4 sample measures 762 ± 76 µm (30 ± 3 mils), about twice the 381 µm (15 mils) of the ICRI CSP 4 chip. A chip match also says nothing about oil, curing compounds or acid residue on the surface.
ASTM D8271 depth micrometer readings#
ASTM D8271-26 measures profile directly with a depth micrometer whose spring-loaded probe sits in the valleys while a 25.4 mm (1 in) base rests on the peaks. The standard, titled "Standard Test Method for Direct Measurement of Surface Profile of Prepared Concrete", was updated on 2026-06-29; the -19 and -21 editions are historical. The inspector takes at least 15 readings in a 152 x 152 mm (6 x 6 in) area, discards outliers and reports the range and the mean. The method resembles ASTM D4417-21 Method B for blast profile on steel, and its SI values are the standard units.
ASTM D7682 replica putty readings#
ASTM D7682-17(2022) measures profile from a replica: two-component epoxy putty is pressed into the surface to a 38.1 mm (1.5 in) impression and read with a micrometer. Under Method B the micrometer, with a 38.1 mm (1.5 in) base, takes 10 readings on the cured replica, and the result is the difference between the lowest and the highest peak-to-valley reading. ASTM describes the method as complementing the ICRI chips, and the cured replica stays on file as a physical record of the surface.
Sampling, reporting and pH records#
AMPP SP21513-2021 sets how many locations each method needs, and the parties agree the count before work when the specification is silent. The guideline, titled "Procedure for Determining Conformance to Concrete Surface Profile Requirements", was published on 2021-10-06. The three records an inspector keeps for every area are listed below.
- Record the method and the comparator used (ICRI chips, licensed samples, D8271 or D7682).
- Record the range and the mean of the readings in µm (mils) with the CSP range from the data sheet.
- Record the ASTM D4262-05(2024) result after any acid etching or chemical cleaning; the method only shows whether the surface is acidic or alkaline, and Sherwin-Williams guidance targets a final pH of 10 or higher after rinsing.
Which Surface Preparation Methods Produce Each Concrete Surface Profile?#
ICRI 310.2R-2013 lists 13 concrete surface preparation methods, from detergent scrubbing to a handheld concrete breaker, and the specifier chooses among them by the CSP range the product needs and the condition of the substrate.
One of the 13, the surface retarder, applies only to freshly placed cementitious materials, which is the territory of surface retarders for exposed aggregate concrete.
The table below pairs each listed method with the ICRI chip it made and with product values that name the method.
| Method (ICRI 310.2R-2013 list) | ICRI chip it made | Note | Product (data sheet, edition) |
|---|---|---|---|
| Detergent scrubbing | None | Cleaning only; ASTM D4258-23 covers surface cleaning of concrete | |
| Low-pressure water cleaning | None | Below 34 MPa (5,000 psi) | Sherwin-Williams water and wastewater preparation guide |
| Grinding | CSP 2 | Thin films; polished concrete floors are a separate finished system | Sikafloor-264 Plus: grind high spots for thin layers; substrate at least 25 N/mm² (3,626 psi) compressive and 1.5 N/mm² (218 psi) tensile |
| Acid etching | CSP 1 | ASTM D4260-23; pH check by ASTM D4262-05(2024) | Neogard Auto-Gard guide specification (July 2021): 10 to 15 % muriatic acid only where shot blasting is impractical |
| Needle scaling | None | No chip | |
| Abrasive blasting | CSP 7 (heavy) | ASTM D4259-24 covers preparation by abrasion | |
| Shotblasting | CSP 3 and CSP 5 | Dry pass over slabs | Neogard Auto-Gard guide specification (July 2021): CSP 3 to 4 by shot blasting |
| High- and ultra-high-pressure water jetting | CSP 10 (after a breaker) | 34 to 310 MPa (5,000 to 45,000 psi) | SikaCem-103: high-pressure water blast or scabble to an exposed-aggregate CSP 6 |
| Scarifying | CSP 4, 6 and 9 | Bruising risk | |
| Surface retarder | None | Freshly placed cementitious materials only | |
| Rotomilling | CSP 9 | Bruising risk | |
| Scabbling | CSP 8 | Bruising risk | SikaCem-103 (as above) |
| Handheld concrete breaker | CSP 10 (with blasting or water jetting) | Removal of unsound concrete |
The chip column records how each ICRI chip was made, not the range a method can reach.
Detergent scrubbing and water cleaning#
Detergent scrubbing and low-pressure water cleaning remove dirt and loose material without roughening sound concrete. ASTM D4258-23 covers surface cleaning of concrete before coating. Sherwin-Williams' water and wastewater preparation guide defines low-pressure water cleaning as below 34 MPa (5,000 psi) and high-pressure water jetting as 34 to 310 MPa (5,000 to 45,000 psi). Neither cleaning method made an ICRI chip, so a surface cleaned this way still needs a profiling method where the data sheet asks for a CSP number.
Acid etching concrete#
Acid etching made the CSP 1 chip, and ASTM D4260-23 covers liquid and gelled acid etching of concrete. The method has three limits: the acid is hard to rinse out fully, it does not remove oil, and mechanical profiling is preferred where the product allows a choice. Every etched surface gets a pH check under ASTM D4262-05(2024) before coating.
Makers disagree on etching: the Neogard Auto-Gard guide specification (July 2021) allows a 10 to 15 % muriatic acid etch only where shot blasting is impractical, while Sikalastic Vehicular Traffic 2900 does not permit acid etching at all. Muriatic acid is the trade name of hydrochloric acid, whose hazard line appears in the safety section below.
Concrete grinding for epoxy and thin coatings#
Grinding made the CSP 2 chip, and it removes laitance and high spots with little amplitude, which suits thin films whose data sheet asks for a low CSP. Grinding for epoxy flattens ridges and opens the paste before a thin roller coat or self-priming film, a standard preparation for resin and industrial floor coatings.
Shot blasting concrete#
Shot blasting made the CSP 3 and CSP 5 chips (light and medium shotblast), and it profiles slabs in one dry pass. The machine throws steel shot at the surface, recovers it and collects the dust, so the prepared slab is ready for profile and cleanliness checks without rinsing. ASTM D4259-24 covers preparation of concrete by abrasion, the group shot blasting belongs to.
Scarifying, scabbling and rotomilling concrete#
Scarifying made the CSP 4, 6 and 9 chips (light, medium and heavy, the last rotomilled) and scabbling made CSP 8, so these methods serve repair mortars and grouts rather than thin coatings. Scabbling, rotomilling and scarifying bruise the surface, leaving microcracked concrete below the profile that a bonded product cannot rely on. Repair mortar and grout data sheets in the product-class table ask for CSP 5 or rougher, and SikaFlow-648 excludes a bushing hammer.
Waterjetting and hydrodemolition#
Waterjetting runs from 34 to 310 MPa (5,000 to 45,000 psi) for high-pressure work, and ICRI 310.3R-2014 covers hydrodemolition for repair. Water jetting finished the CSP 10 chip after a handheld breaker, and it leaves no dust.
What CSP Does Each Product Class Require?#
The product maker sets the CSP, so every requirement below is a data-sheet value of the named product: floor primers and polyaspartic coatings ask for CSP 3 or CSP 3 to 4, and repair mortars and grouts ask for CSP 5 or rougher. No standard sets one CSP for a product class, and two products of the same class can differ by two steps.
The table below lists the CSP each named product requires.
| Product class | Product (data sheet, edition) | CSP required | Other preparation condition |
|---|---|---|---|
| Concrete primers for coatings and resin floors | Sikafloor-161 (US) | CSP 3 to 4 | |
| Polyaspartic and polyurea floor coatings | GP4850 | CSP 3 | Vapor or moisture barrier on slab on grade |
| Moisture mitigation systems for concrete slabs | Mapei Planiseal VS; ARDEX MC Rapid (guide specification 2023-06); ASTM F3010-24 default | CSP 2 to 3 (Planiseal VS); CSP 3 (MC Rapid, F3010-24) | No acid etching; Planiseal VS substrate tensile at least 1.03 MPa (150 psi) by ASTM D7234-22 |
| Traffic coatings for parking decks and plazas | Neogard Auto-Gard (guide specification July 2021); Sikalastic Vehicular Traffic 2900 | CSP 3 to 4 (Auto-Gard); minimum CSP 3 (2900) | Shot blasting; no acid etching (2900) |
| Chemical-resistant linings | Tnemec Series 239; Tnemec Series 120 (vinyl ester) | Minimum CSP 3 (239); CSP 5 (120) | |
| Coatings for potable water tanks | Tnemec N140; Tnemec Series 22 | CSP 2 (N140); CSP 5 (Series 22) | 28-day cure |
| Sewer manhole and wet-well linings | Tnemec 435 | Minimum CSP 5 | |
| Cementitious waterproofing | SikaTop Seal 107 | CSP 3 | Saturated surface dry (SSD) |
| Crystalline waterproofing coatings | CEM-KOTE CW PLUS | Minimum CSP 3 | Pull-off at least 1 MPa (145 psi) |
| Concrete repair mortars | SpecChem RepCon 928; SikaQuick-2500 | Minimum CSP 5 (RepCon 928); CSP 6, about 3 mm profile (SikaQuick-2500) | SSD |
| Shotcrete and sprayed repair mortars | SikaCem-103 | CSP 6 | High-pressure water blast or scabble |
| Non-shrink grout | SikaGrout-212; SikaGrout-928 | CSP 4 or higher (212); CSP 5 to 9 (928) | |
| Epoxy machinery grouts | SikaFlow-648 | CSP 5 to 9 | No bushing hammer |
One maker publishes a rule by film build instead of by product, shown in the table below as guidance from that maker only.
| System (Sherwin-Williams guidance) | CSP |
|---|---|
| Linings up to 508 µm (20 mils) DFT | CSP 2 to 3 |
| Linings up to 1,016 µm (40 mils) DFT | CSP 3 to 5 |
| Laminates and self-leveling mortars | CSP 4 to 6 |
| Repair and polymer mortars | CSP 5 to 9 |
Specify a CSP range from the data sheet#
A specification states a CSP range, not a single number, and copies it from the data sheet of the product being applied. Concrete age is part of the same clause: the Carboguard 880 data sheet asks for 28 days at 23.9 °C (75 °F) and 50 % RH or design strength, and FDOT allows no epoxy overlay on concrete younger than 28 days.
Pull-off verification of the prepared surface#
A preparation trial proves the profile by pull-off: FDOT Dev403EO (rev 2020-08-11) accepts a trial area when 3 pulls average at least 1.72 MPa (250 psi) and none falls below 1.21 MPa (175 psi). The specification also accepts a trial when the failure runs at least 6.35 mm (1/4 in) into the base concrete over at least 50 % of the 50.8 mm (2 in) dolly, on a trial area of 0.46 x 0.91 m (1.5 x 3 ft). Dolly geometry and failure modes are covered under pull-off adhesion testing.
ASTM C1583/C1583M-25, the method behind most concrete pull-off trials, sets no pass or fail value. The acceptance number comes from the specification or the data sheet, such as the 1 MPa (145 psi) minimum in the product-class table.
What Are the Common Concrete Surface Profile Errors?#
Concrete surface profile errors come from treating CSP as a depth scale, as a cleanliness test or as "rougher is better": chip depths overlap, a chip match ignores contamination, and excess roughness wastes material and can bruise concrete. Practical coverage equals theoretical coverage times (1 minus the loss), and a maker's coverage figure is theoretical, excluding profile and waste, so a rougher profile than the data sheet asks for raises consumption.
Profiling also opens pores and bug holes that release air while a coating cures. Mapei Planiseal VS asks for a wait of 16 to 24 h after mechanical profiling where outgassing is a risk, one of the controls for outgassing and blistering in concrete floor coatings.
The table below lists eight errors, their consequence and the check that catches each one.
| Error | Consequence | Check |
|---|---|---|
| Depth read as a CSP number | CSP 1 and 2, and CSP 4 and 5, overlap in measured depth | Report CSP by chip match and depth in µm (mils) separately |
| Comparator not named | Licensed samples measure differently from ICRI chips | Record chip set or sample set |
| Profile without cleanliness | Oil, curing compounds or acid residue left on a profiled surface | Cleanliness and pH checks besides CSP |
| Acid-etched floor coated | Peeling of poorly prepared (acid-etched) garage floor coatings | Mechanical profile where the data sheet requires it |
| Smooth formed surface under a crystalline coating | Steel-formed surfaces with closed capillaries (profile below CSP 3) | Chip check against the CSP 3 minimum |
| Traffic coating over laitance | Debonding from poor CSP or laitance | Shot blast to the data-sheet range |
| Profile rougher than the range | Higher consumption; bruising with scabbling, scarifying or rotomilling | Specify a range and stop at its upper end |
| No pull-off trial | Bond not proven before full production | Trial by ASTM C1583 pull-off tensile strength method, acceptance from the specification |
Silica and Acid Safety During Concrete Surface Preparation#
Grinding, blasting and scarifying concrete release respirable crystalline silica, regulated in US construction by OSHA 29 CFR 1926.1153 at a PEL of 50 µg/m³ and an action level of 25 µg/m³ (8-hour TWA). The rule took effect on 2016-06-23, with construction obligations from 2017-06-23, and acid etching adds a corrosive acid to the dust hazard. Table 1 of the rule names controls for walk-behind grinders and milling machines, handheld grinders and jackhammers; housekeeping under paragraph (f) bans dry sweeping, dry brushing and compressed air where low-exposure alternatives are feasible, and paragraph (g) requires a written exposure control plan reviewed at least annually and a competent person. In the EU, the binding limit is 0.1 mg/m³ of respirable crystalline silica under Directive (EU) 2017/2398.
Quartz (crystalline silica), CAS 14808-60-7, has no Annex VI entry; no hazard statement reaches a majority of ECHA C&L notifications, so classification is product-specific (see supplier SDS). Hydrochloric acid, CAS 7647-01-0, carries the harmonised CLP Annex VI classification under index 017-002-01-X: H314, H335.
The table below collects the rules and classifications that apply during preparation.
| Topic | Rule or classification | Instrument and date |
|---|---|---|
| Respirable crystalline silica | PEL 50 µg/m³ and action level 25 µg/m³, 8-hour TWA | OSHA 29 CFR 1926.1153, effective 2016-06-23 |
| Walk-behind grinders and milling machines | Integrated water feed, or dust collector with at least 99 % filter efficiency and HEPA vacuuming indoors | 1926.1153 Table 1 |
| Handheld grinders | Water feed, or shroud plus dust collector of at least 0.71 m³/min per 25.4 mm (25 cfm per inch) of wheel diameter | 1926.1153 Table 1 |
| Jackhammers | APF 10 respirator indoors | 1926.1153 Table 1 |
| Housekeeping and plan | No dry sweeping, dry brushing or compressed air for cleaning; written exposure control plan reviewed at least annually; competent person | 1926.1153 (f) and (g) |
| Shotblasters and scarifiers | Exposure assessed by the employer where no Table 1 row is followed | 1926.1153 |
| Quartz (crystalline silica) | No Annex VI entry; no hazard statement in a majority of ECHA C&L notifications; classification is product-specific, see supplier SDS | ECHA C&L, checked 2026-10-20 |
| EU limit | 0.1 mg/m³ respirable crystalline silica, binding | Directive (EU) 2017/2398 amending 2004/37/EC |
| Hydrochloric acid (muriatic acid) | Harmonised CLP Annex VI (index 017-002-01-X): Skin Corr. 1B H314, STOT SE 3 H335; Skin Corr. 1B at 25 % or more, Skin Irrit. 2 and Eye Irrit. 2 from 10 to 25 % | ECHA C&L, checked 2026-10-22 |
Where Is Concrete Surface Profile Specified? Standards, Test Methods and Product Classes#
Concrete surface profile is specified wherever a product must bond to concrete: floor coatings and primers, linings, waterproofing coatings, repair mortars and grouts, each citing ICRI 310.2R-2013 for the scale and its own data sheet for the range.
The test methods behind it, ASTM D8271-26, D7682-17(2022) and the pull-off trial, sit with the other application and test methods on this site.
The six product groups whose specifications carry a CSP clause are listed below.
- Self-leveling concrete and underlayments: mechanical cleaning such as shot blasting, with no acid etching, adhesive removers, solvents or sweeping compounds, in the guidance of two makers.
- Epoxy flooring: profile set by the build-up, from thin roller coats to troweled mortars.
- Protective coatings for concrete and steel: profile on concrete rising with dry film thickness.
- Waterproofing membranes and systems: cementitious and crystalline coatings bonded to concrete at CSP 3.
- Concrete bonding agents: bond coats placed on profiled, laitance-free concrete.
- Repair mortars and grouts: CSP 5 or rougher in the named data sheets.
How Does Surface Profile Fit Into Concrete Surface Preparation Quality Control?#
Profile is one of four checks before a coating goes on concrete: profile, cleanliness, moisture and strength, and a surface can pass CSP while failing the other three. Strength is a data-sheet value, such as the 25 N/mm² (3,626 psi) compressive and 1.5 N/mm² (218 psi) tensile substrate of Sikafloor-264 Plus.
Moisture is measured by in-situ relative humidity under ASTM F2170-19a or by calcium chloride under ASTM F1869-23, and neither method sets a pass or fail value: the limit is the product maker's. Both methods are compared under concrete moisture testing.
Concrete surface profile FAQs#
What does CSP 3 mean?#
CSP 3 is the profile of the light-shotblast ICRI chip, measured at 279 ± 51 µm (11 ± 2 mils) by ASTM D8271. It is the CSP that the GP4850 polyaspartic and SikaTop Seal 107 data sheets ask for.
Does a rougher profile always bond better?#
No: the data sheet sets a range, and a profile rougher than it raises consumption. With scabbling, scarifying or rotomilling it can also bruise the surface.
Is there a CSP number for steel?#
No: CSP is a concrete scale, and steel anchor profile is measured in µm (mils) under ASTM D4417-21.
Cleanliness and profile on steel follow the steel surface preparation grades.
Is acid etching enough before an epoxy floor coating?#
Not where the data sheet forbids it: acid etching made only the CSP 1 chip and leaves residue that must test alkaline under ASTM D4262-05(2024). Moisture mitigation systems and Sikalastic Vehicular Traffic 2900 exclude it.