Single-pack direct-to-metal (DTM) one-coat system that actively bonds and neutralizes structural surfaces, formulated to substitute primer, intermediate and topcoat configurations adhering to international environmental protection policies.
Recognized as the top-performing one-coat system in Federal Highway Administration (FHWA) tests since the 1980s, HRCSA was introduced as an overcoating (encapsulating) system as an alternative to traditional primer, intermediate and topcoat configurations, eliminating the need for sweep or grit blasting while also being acknowledged as ideal for zone coating. The technology cuts project overheads, reduces surface preparation and product application time, and preserves site conditions, resulting in minimal environmental pollution.
Active Interfacial Neutralization
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd (HRCSA) anti-corrosion coating is a highly engineered, single-component polymer architecture that chemically alters the interfacial environment to actively inhibit corrosion. As an over-based sulfonate-carbonate complex widely recognised as a bridge maintenance overcoating system the product is applied onto zinc bearing steel (Hot Dip Galvanizing), direct to metal (DTM) onto un-galvanised metal that is not corroding or over tightly adherent corrosion. The HRCSA by formulation is highly effective in encapsulating tightly adherent weathered coatings as a one coat high-performance solution to protect assets managed by many Departments of Transport (DOT) throughout the US.
Active Interfacial Neutralization
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd (HRCSA) one coat active corrosion protection coating system is single-component polymer architecture that chemically alters the interfacial environment to actively inhibit corrosion. As an over-based sulfonate-carbonate complex formulated as a bridge maintenance overcoating system, the product is applied to zinc bearing steel (Hot Dip Galvanized), un-galvanised metal with tightly adherent corrosion and where grit blasting is still being specified. The HRCSA encapsulates tightly adherent weathered coatings, actively sealing off assets that are managed by Departments of Transport (DOT) throughout the US.
STOP RUST HERE
Applied onto low-traffic surfaces, HRCSA bonds to and neutralises the following substrates.
Direct-to-metal application to smooth or weathered hot-dip galvanised surfaces.
Learn more →
Bonding to the surface
HRCSA bonds through a coordinating mechanism using electrostatic attraction, allowing direct-to-metal application to smooth or weathered zinc-coated (hot-dip galvanised) substrates.
Hydrophobic protection
The over-based calcium sulfonate matrix forms a thixotropic, overlapping lattice of crystalline calcite (CaCO₃) platelets. The hydrophobic, self-healing matrix seals the treated surface from moisture, inhibiting sacrificial zinc consumption.
Active neutralisation
The supplied formulation description identifies an alkaline sulfonate-carbonate complex that raises the surface pH to ≥ 10.1 and actively neutralises the treated surface.
02
Electroplated metal components
Included among the substrates listed for low-traffic applications.
Learn more →
Application scope
Electroplated metal components are included in the supplied list of substrates. RUSTOPAK® bonds to and neutralises these substrates when applied onto low-traffic surfaces.
03
Ungalvanised steel, rust-free
Direct-to-metal protection for ungalvanised steel without corrosion.
Learn more →
Suitable substrate
The supplied Top Coat description includes direct-to-metal application onto ungalvanised metal that is not corroding.
Surface condition
Surfaces must be completely dry and free of contaminants, including oil, grease, salt and dirt, prior to application.
04
Ungalvanised steel with tightly adherent rust
Treatment of steel where corrosion remains tightly attached.
Learn more →
Tightly adherent corrosion
The supplied Top Coat description states that total removal of tightly adherent corrosion is not required. Tightly adherent rust on structural steel must be completely dry and free of contaminants, including oil, grease, salt and dirt, prior to application.
Hard-to-reach areas
RUSTOPAK® Penetrant (Aerosol) is designed for wetting into hard-to-reach areas. Capillary action enables the product to wick into crevices without dismantling structures. The supplied system instructions pair the Penetrant with RUSTOPAK® Top Coat.
05
Firmly adherent coatings
Overcoating of compatible, tightly adherent weathered coatings.
Learn more →
Coating compatibility
The supplied Top Coat instructions allow direct application over compatible, tightly adherent weathered coatings and refer to a specific approved coating list.
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KEY FEATURES
How RUSTOPAK® HRCSA Delivers Active Protection
01
Electrostatic Bonding Mechanism
Learn more →
High Ratio Calcium Sulfonate Alkyd bonds through a strong coordinating mechanism, using electrostatic attraction, allowing direct-to-metal (DTM) application to smooth or weathered zinc-coated (hot-dip galvanized) substrates also adhering to metals, oxides and compounds on weathered structures unlike conventional primer, intermediate and topcoat systems, which obtain adhesion through hydroxyl, carboxyl and epoxide groups which usually requires a substrate profile achieved by grit or sweep blasting to create a profile for primer coat mechanical interlocking.
The direct to metal (DTM) product, due to van der Waals forces has a greater attraction to metal than water, as its primary method of adhesion, not requiring grit or sweep blasting for mechanical interlocking adhesion to metal surfaces before coating. Modified calcium sulfonate/carbonate complexes obtain adhesion through charge attraction. The positively charged calcium and double bonded oxygen’s have a strong affinity for the negatively charged metal surfaces, a different adhesion mechanism to conventional coating systems that obtain adhesion through hydroxyl, carboxyl and epoxide groups which usually requires a substrate profile achieved by grit or sweep blasting. The modified calcium sulfonate system is not affected by the ions generated during the corrosion process that normally causes undercutting.
In molecular physics, the van der Waals forces are distance-dependent interactions between atoms or molecules. Unlike ionic or covalent bonds, these attractions are not a result of any chemical electronic bond and they are comparatively weak and more susceptible to being disturbed. Van der Waals forces quickly vanish at longer distances between interacting molecules. Van der Waals forces also define many properties of organic compounds and molecular solids, including their solubility in polar and non-polar media.
Polarity
The polarity of the aromatic ring and attached sulfonate (SO3) group results in a product with superb metal wetting and moisture displacement properties. The polar end of the sulfonate/carbonate complex attaches to metallic substrates and demonstrates exceptional adhesion even when the film is damaged. Very thin films of only a few mils (1 mil = 25.4 µm) can offer up to 1,000 hours of protection in the ASTM B 117 Salt Fog Test. The moisture displacement property allows the application of the product in less than optimal conditions.
02
Active Surface Neutralization
Learn more →
High Ratio Calcium Sulfonate Alkyd stops corrosion cell formation through an active sulfonate-carbonate complex. Its dense, alkaline core continuously raises the surface pH ≥ 10.1 actively neutralizing both metal and zinc-coated (hot-dip galvanized) substrates, preventing further oxidation.
Neutralization and Over-Basing
Sulfonic acid is converted into the sulfonate-carbonate complex by neutralizing the sulfonic acid and reacting with the metal salt with an excess of calcium hydroxide and calcium oxide to form the over-based complex.
Interfacial Environmental Modification
The direct to metal (DTM) One-Coat product causes a neutralization reaction between the mild sulfonic acids (RSO3H) in the formulation and the zinc carbonate (ZnCO3) layer present on galvanized surfaces, producing a robust, integrated zinc sulfonate matrix. This neutralization bond, combined with the dense alkaline core of the overbased complex, permanently raises the local interfacial environment to an alkaline pH ≥ 10.1. Because zinc and carbon steel corrosion cells require an acidic environment to thrive, this sustained alkaline shift renders the environment thermodynamically too basic for corrosion formation, arresting zinc and iron oxidation and sub-film under-creep.
Corrosion Inhibition
The calcium carbonate (CaCO3) part of the complex functions primarily as an alkalinity reserve. The carbonate is slightly soluble in water and acts as a corrosion inhibitor by buffering the pH at the local metal surface. A pH ≥ 10.1 is maintained at the coating/metal interface, which delays the onset of the corrosion process and actively prevents under cutting (undercreepage), an essential characteristic of an active joint sealant.
03
Hydrophobic, Self-Healing Matrix
Learn more →
The permanently hydrophobic and self-healing matrix of High Ratio Calcium Sulfonate Alkyd seals smooth or weathered zinc-coated (hot-dip galvanized) substrates inhibiting sacrificial zinc consumption and further oxidation of metals and existing compounds. This outward-facing hydrocarbon array creates a dense, non-polar hydrophobic membrane that repels moisture, ionic species and oxygen, effectively suppressing cathodic and anodic corrosion cell formation.
The hydrophobic product cures to a firm finish (ASTM D3363) of 5B Pencil Hardness and passes the (ASTM D522) 180° Mandrel Bend Test. The product remains permanently firm, accommodating Linear Coefficient of Thermal Expansion (LCTE) of the underlying steel substrate during extreme thermal fluctuations without experiencing embrittlement, micro-cracking, or delamination at structural connections.
Once the modified calcium sulfonates have “plated out” with their charged groups toward the metal they orient towards, a very hydrophobic hydrocarbon chain structure outward is established. This environment prevents water from reaching the metal as the calcite platelets increase the path length that oxygen or water would need to take to reach the metal substrate. The hydrophobicity is further increased by the chemical constituents that form the matrix between the platelets (wax, OXPET), which are also hydrophobic.
04
Surface Encapsulation
Learn more →
Surface encapsulation in High-Ratio Calcium Sulfonate Alkyd is driven by the immediate chemical and physical interactions at the substrate interface. Charged polar sulfonate groups and van der Waals forces wet and anchor directly to smooth or weathered substrates without requiring abrasive sandblasting, effectively displacing moisture and encapsulating the metal at a molecular level. Simultaneously, an over-based calcium carbonate core continuously buffers the coating interface to an alkaline pH ≥10.1 creating an environment where active corrosion and sub-film under-creep are thermodynamically unable to form.
Beyond interfacial bonding and neutralization, long-term encapsulation relies on the matrix's structural durability and protective shield. Outward-oriented hydrocarbon chains and aligned calcite platelets form a dense, hydrophobic barrier that blocks moisture and oxygen ingress while remaining permanently flexible to accommodate structural thermal expansion without cracking. Combining an organic sulfonate backbone with an inorganic colloidal calcium core yields an organic-inorganic hybrid system that, when applied over hot-dip galvanizing, provides a synergistic duplex effect extending service life by 1.5 to 2.5 times protected by integrated UV inhibitors that prevent surface degradation under severe solar exposure.
05
Hybrid Duplex Protection
Learn more →
High Ratio Calcium Sulfonate Alkyd is an organic-inorganic hybrid (sulfonate organic and calcium inorganic complex) duplex coating that actively delivers extended protection of zinc-coated (hot-dip galvanized) substrates.
Standards - HDGASA
ISO 1461 International Standard for hot dip galvanizing (zinc-coated substrates) - ISO 1461 refers to ISO 12944 Duplex coating of hot dip galvanizing (zinc-coated substrates). ISO 12944 “Duplex" system combines hot-dip galvanizing with an organic paint or powder coating. This pairing creates a powerful, synergistic effect where the life expectancy of the combined system is generally (1.5 to 2.5) times the lifespan of either system used independently.
Over-Based Calcium Sulfonate
High Ratio Calcium Sulfonate is an organic-inorganic hybrid rather than purely organic or purely inorganic product. The base structure of the product relies on an organic sulfonate component. To achieve superior anti-corrosion and water-resistant properties, the product is over-based. Excess calcium (an inorganic metal) is added to form a colloidal suspension of inorganic calcium carbonate (CaCO3) held in a lattice by the organic sulfonate.
Interfacial Environmental Modification
The direct to metal (DTM) One-Coat RUSTOPAK® product causes a neutralization reaction between the mild sulfonic acids (RSO3H) in the formulation and the zinc carbonate (ZnCO3) layer present on galvanized surfaces, producing a robust, integrated zinc sulfonate matrix. This neutralization bond, combined with the dense alkaline core of the overbased complex, permanently raises the local interfacial environment to an alkaline pH ≥ 10.1. Zinc and carbon steel corrosion cells require an acidic environment to thrive, this sustained alkaline shift renders the environment thermodynamically too basic for corrosion formation, arresting zinc and iron oxidation and sub-film under-creep.
This complex is dispersed in Mineral Turpentine/Spirits and exhibits a variety of properties, which relate to the chemical structure of over-based gelled calcium sulfonate. These include hydrophobicity due to platelet formation, polarity and corrosion inhibition. The calcium sulfonate resin provides the excellent corrosion resistance, water resistance, adhesion to bare metal and hot dip galvanized steel.
06
Integrated UV Protection
Learn more →
High Ratio Calcium Sulfonate Alkyd integrated proprietary UV protection technology, formulated for long-term exposure within extreme solar radiation parameters, ensures longevity of the active overcoating system.
The UV protection technology is formulated to help mitigate the adverse effects of prolonged ultraviolet (UV) radiation on the coating film, including UV-induced degradation, surface deterioration, loss of protective properties, and premature coating ageing. By supporting the integrity of the coating's protective film, the product’s integrated proprietary UV protection technology contributes to the sustained performance of the corrosion mitigation system throughout its intended service life particularly where infrastructure such as utility-scale solar park installations are subjected to elevated solar radiation, temperature fluctuations and outdoor weathering.
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RUSTOPAK® Penetrant (Aerosol) is a low-VOC, single-component penetrating liquid designed for superior wetting into hard-to-reach areas.
Used in conjunction with RUSTOPAK® Top Coat, it eliminates the need to dismantle and reassemble components during treatment.
01
Wetting and penetration
Reaches deep into tight crevices where zinc corrosion is accelerated and joints are corroding.
02
Access without dismantling
Treats hard-to-reach areas directly, saving labour and time.
03
Used with Top Coat
Used in conjunction with RUSTOPAK® Top Coat to treat inaccessible areas.
Select a heading to explore the technical detail.
Penetration and corrosion-prone areas
Specially formulated to treat inaccessible areas prone to differential aeration, bimetallic and crevice corrosion through its polar formulation and neutralisation to pH 10.1.
Capillary action enables the product to wick deep into areas that are hard to reach without dismantling structures, displacing moisture and oxygen and encapsulating the treated micro-environment.
At the same time, it neutralises the interfacial surfaces where zinc from hot-dip galvanising is depleted and rust causes damage to critical sections of structures.
Solar mounting structures
Utility-scale solar mounting structures are an example of where active protection is needed before the application of RUSTOPAK® Top Coat to stop accelerated corrosion of zinc.
Engineers should identify the areas on structures where corrosion initiates first.
Crevice application
Spray applied directly into hard-to-reach crevices over tightly adherent pack rust (exfoliation corrosion).
Top Coat
Overview
RUSTOPAK® Top Coat is a single-component, specially formulated active sealant system designed as a high-performance, direct-to-metal (DTM), one-coat anti-corrosion coating.
It features low volatile organic compound (VOC) emissions.
No need for total removal of tightly adherent corrosion.
03
Weathered coatings
Direct application over compatible, tightly adherent weathered coatings. Refer to the specific approved coating list.
Select a heading to view preparation and application details.
Surface preparation
Tightly adherent rust on structural steel must be completely dry and free of contaminants, including oil, grease, salt and dirt, prior to application.
Application method
System pair: Overcoat directly onto RUSTOPAK® Penetrant (Aerosol).
Technique: Apply using a wet-on-wet application method.
Application & Quality Control
Application Conditions
Select a heading to view the application requirements.
Rain
Apply only when no rain is anticipated on the day of application and the surfaces are completely dry.
Wind
Wind speed must be low during spray application. If the wind speed is too high, use roller or brush application. Overspray must be contained using suitable protection such as wind fencing, tarpaulins and drop-out sheeting.
If overspray lands on equipment that is not specified to be coated, it is the applicator’s responsibility to remove it using mineral turpentine and a clean cloth.
Temperature and climatic checks
Surface temperatures between -7 °C and 54 °C can be coated. The surface temperature must be at least 3 °C above the dew point. If the difference is less than 3 °C, condensation may form on the substrate.
For coating application, the surfaces must be completely dry.
Climatic readings are a hold point and must be inspected by a qualified coating inspector or supervisor using appropriate equipment such as a dew point meter. Readings of climatic conditions must be submitted through www.rustopak.com.
Top Coat Application Requirements
Application Conditions
Select a heading to view the application requirements.
Rain
Apply only when no rain is anticipated on the day of application and the surfaces are completely dry.
Wind
Wind speed must be low during spray application. If the wind speed is too high, use roller or brush application. Overspray must be contained using suitable protection such as wind fencing, tarpaulins and drop-out sheeting.
If overspray lands on equipment that is not specified to be coated, it is the applicator’s responsibility to remove it using mineral turpentine and a clean cloth.
Temperature and climatic checks
Surface temperatures between -7 °C and 54 °C can be coated. The surface temperature must be at least 3 °C above the dew point. If the difference is less than 3 °C, condensation may form on the substrate.
For coating application, the surfaces must be completely dry.
Climatic readings are a hold point and must be inspected by a qualified coating inspector or supervisor using appropriate equipment such as a dew point meter. Readings of climatic conditions must be submitted through www.rustopak.com.
The thermodynamic instability of metals drives corrosion. Many metals occur naturally as stable, lower-energy compounds in ores. Extracting them requires energy, leaving the refined metal in a higher-energy state relative to those compounds. Under suitable environmental conditions, metals react to form more stable compounds. In atmospheric corrosion, this electrochemical process requires a corrosion cell. Moisture, oxygen, salts and differences in electrical potential can support corrosion-cell activity at joints, fasteners, crevices and weathered steel surfaces. Visible rust is often only the final sign of activity that began beneath or between connected surfaces.
CREVICES & JOINTS
Water and contaminants can remain trapped where surfaces meet, creating a concentrated local environment for corrosion.
GALVANIC CONTACT
Electrical connection between dissimilar metals can accelerate local corrosion where moisture completes the circuit.
WEATHERED STEEL
Damaged coatings and tightly adherent corrosion create difficult maintenance conditions that require a considered protection strategy.
RUSTOPAK® TECHNICAL GUIDANCE AVAILABLE ON REQUEST
TECHNOLOGY
A COATING SYSTEM DESIGNED TO CHANGE THE INTERFACE.
RUSTOPAK® High Ratio Calcium Sulfonate Alkyd (HRCSA) one coat active corrosion protection coating system is single-component polymer architecture that chemically alters the interfacial environment to actively inhibit corrosion. As an over-based sulfonate-carbonate complex formulated as a bridge maintenance overcoating system, the product is applied to zinc bearing steel (Hot Dip Galvanized), un-galvanised metal with tightly adherent corrosion and where grit blasting is still being specified. The HRCSA encapsulates tightly adherent weathered coatings, actively sealing off assets that are managed by Departments of Transport (DOT) throughout the US.
BOND
Polar chemistry supports metal wetting, moisture displacement and direct-to-metal adhesion.
SEAL
A high-film-build coating creates a hydrophobic barrier against moisture, oxygen and contaminants.
MODIFY
An alkaline reserve supports an interfacial environment less favourable to ongoing corrosion activity.
The following terms explain the use of this website and how RUSTOPAK (Pty) Ltd handles personal information submitted through RUSTOPAK®.
WEBSITE TERMS OF USE
1. ACCEPTANCE OF TERMS
By accessing or using rustopak.com, you agree to these Website Terms of Use. If you do not agree, please do not use this website.
2. WEBSITE INFORMATION
The technical information on this website is provided for general information only. It does not replace a project-specific assessment, product data sheet, application specification or written recommendation from RUSTOPAK®.
3. INTELLECTUAL PROPERTY
All website content, including text, graphics, logos, technical material and images, is the property of RUSTOPAK (Pty) Ltd, RUSTOPAK® or its authorised content providers, and may not be reproduced without written permission.
4. LIMITATION OF LIABILITY
To the fullest extent permitted by law, RUSTOPAK (Pty) Ltd shall not be liable for loss or damage arising from use of this website or reliance on its general information. Technical suitability must be confirmed for the relevant asset, environment and application.
5. GOVERNING LAW
These Website Terms of Use are governed by the laws of the Republic of South Africa.
PRIVACY & POPIA NOTICE
1. PERSONAL INFORMATION WE COLLECT
We may collect personal and business information you submit through enquiries, technical-information requests, data-upload forms and direct correspondence. This may include your name, contact details, company details, project information and supporting files.
2. HOW WE USE INFORMATION
We use this information to respond to enquiries, assess technical requirements, provide requested information, manage business communications and improve our services.
3. DISCLOSURE AND SECURITY
We do not sell or rent personal information. Access is limited to authorised personnel and service providers where necessary for the stated purpose, or where disclosure is required by law. We apply reasonable safeguards to protect information in our possession.
4. YOUR RIGHTS
You may request access to, correction of or deletion of your personal information where applicable. To make a request or raise a privacy concern, contact us at [email protected].
RUSTOPAK (Pty) Ltd Registration Number: 2017/525641/07 rustopak.com · [email protected] Last updated: 20 September 2026
Evidence & Resources
Bibliography
Research, technical guidance and industry references informing RUSTOPAK® corrosion-protection practice and its application to targeted infrastructure maintenance.
Section 18.3.5 identifies high ratio calcium sulfonate within bridge zone preventive-maintenance systems, including spot treatment of corroded areas and zone overcoating.
Relevant section: 18.3.5, Example Preventive Maintenance Painting Systems
Peer-reviewed national research mapping atmospheric corrosivity across South Africa using ISO 9223:2012 categories and measured mild-steel corrosion rates.
Janse van Rensburg, D.T.; Cornish, L.A.; Van der Merwe, J. DOI: 10.17159/sajs.2019/4901
An Investigation into the Methodology to Develop an Insulator Pollution Severity Application Map for South Africa
A South African study examining salt deposition, atmospheric pollution and corrosion measurements along coastal-to-inland electrical infrastructure routes.
BS 5493:1977, Code of Practice for Protective Coating of Iron and Steel Structures Against Corrosion
Historic protective-coating guidance from the pre-ISO 12944 era, reflecting established principles of coating-system selection and maintenance planning.
BS 5493:1977. Historical reference; see BSI for current status.
The sources listed here provide technical and industry context. Their inclusion does not imply endorsement of RUSTOPAK® by the publishing organisation.
Technical Support
Frequently Asked Questions
Straightforward answers to common questions about HRCSA technology, surface preparation, application and suitable service environments.
What is HRCSA?
HRCSA means High Ratio Calcium Sulfonate Alkyd. RUSTOPAK® is a single-component, direct-to-metal coating system formulated to provide active corrosion protection through its protective film and alkaline interfacial environment.
Is RUSTOPAK® a primer or a topcoat?
RUSTOPAK® Top Coat is a one-coat direct-to-metal system formulated to substitute conventional primer, intermediate and topcoat configurations where the assessed substrate and project specification permit its use.
Is abrasive blasting always required?
No. HRCSA maintenance applications can substantially reduce the need for sweep or grit blasting. Loose corrosion, failed coating, contamination and other unsound material must still be removed using the preparation method appropriate to the substrate and project specification.
Can RUSTOPAK® be applied over an existing coating?
It may be applied over compatible, firmly adherent weathered coatings after inspection and suitable preparation. Existing coating condition, adhesion and compatibility must be assessed before application.
Is RUSTOPAK® suitable for C4 and C5 environments?
The system is positioned for demanding C4 and C5 atmospheric exposure conditions using ISO-aligned assessment principles. Final suitability depends on the substrate, local exposure, project specification, preparation and required film thickness.
Can it be used on solar mounting structures and transformers?
Yes, these are important RUSTOPAK® application areas. The system is intended for suitable zinc-bearing and steel infrastructure, including corrosion-prone interfaces, joints and structural components, subject to project assessment and specification.
Is RUSTOPAK® suitable for submerged service?
No. RUSTOPAK® is intended for atmospheric and appropriate non-submerged service conditions. It should not be specified for continuous immersion or submerged service.
What surface preparation is required?
The surface must be sound and suitably prepared. Loose corrosion, loose coating, dirt, grease, salts and other contaminants must be addressed. The final preparation procedure depends on the substrate, existing coating condition and approved project requirements.
What wet-film and dry-film thickness is required?
The standard project reference is 600 μm wet-film thickness, producing approximately 360 μm dry-film thickness. The approved project specification and quality-control requirements remain authoritative.
What is the difference between RUSTOPAK® Penetrant and Top Coat?
RUSTOPAK® Penetrant is a low-viscosity aerosol designed to wet and penetrate difficult joints, crevices and inaccessible areas. RUSTOPAK® Top Coat forms the main protective coating film. Where specified, the products are used together in a wet-on-wet application sequence.
What climatic conditions must be checked during application?
Project records must consider rain, wind, ambient and surface temperature, relative humidity and dew point. Surface temperature must remain at least 3°C above the dew point. Application must follow the approved technical and project requirements.
Where can technical documents and test reports be found?
Use the Evidence & Resources section for technical documents, testing and performance reports, specifications, industry references and bibliography sources.
Have a project-specific technical question that is not answered here?
Submit your completed quality records and supporting documents. Include the technician, company, site and structure details so we can identify your submission.
TECHNICAL TRAINING
Technician Training & Accreditation
Build the knowledge and practical skills to apply Rustopak® with care, consistency and accurate project records.
The programme prepares technicians to work with Rustopak® ISO 9001:2015 aligned Quality Management Instructions (QMI) across industrial coating projects.
HRCSA theoretical training · Course materials and inspection equipment
08Training sessions
5h 40mScheduled presentations & theory examination*
On-sitePractical demonstration & trainee practice
*Approximate total for sessions 1–7, excluding breaks. Practical duration depends on site requirements.
PURPOSE
Competence at every project phase
The objective is to deploy trained, authorised and accredited Rustopak® technicians with the knowledge to follow the QMI, carry out project tasks and maintain the required records.
WHO SHOULD ATTEND
Maintenance contractor teams
Maintenance contractors arrange theoretical and practical training for eligible technicians.
Able to read, speak and write in English.
Physically fit and able and permitted to work at heights.
CORE COMPETENCIES
What technicians will learn
01
Storage & handling
Follow product handling guidelines from receipt through to disposal.
02
Climatic conditions
Assess dew point, relative humidity and surface temperature.
03
Surface checks
Evaluate coating adhesion, surface cleanliness, surface temperature and chloride levels using the applicable inspection and testing requirements.
04
Application skills
Handle products and materials correctly, operate equipment safely and apply the specified wet film thickness (WFT).
05
Product calculations
Calculate product consumption throughout the application process.
06
Quality records
Maintain precise, comprehensive records for the manufacturer, Rustopak and asset owners, following the applicable TDS and QMI requirements.
YOUR TRAINING PATH
From understanding to application
Select a session to see its topics and hold points.
01Corrosion & the Rustopak coating system± 60 min+
Corrosion explained.
Rustopak High Ratio Calcium Sulfonate Coating Service.
02People, toolbox & sample application± 40 min+
Staff details and qualifications — Hold Point 01.
Toolbox — Hold Point 02.
Sample application — Hold Point 03.
03Climatic conditions± 35 min+
Climatic Conditions — Hold Point 04.
Assessing dew point, relative humidity and surface temperature forms part of the programme’s climatic competency requirements.
04Surface conditions± 60 min+
Surface Conditions — Hold Point 05.
Visual inspection of existing coating adhesion.
Visual standard for surface cleanliness of prepared surfaces (particles).
Test for chlorides.
Surface temperature measurement.
05Application & film thickness± 65 min+
Application — Hold Point 06.
Wet Film Thickness Gauge.
Dry Film Thickness: Non-destructive Test.
06Storage, handling & waste disposal± 35 min+
Storage & Handling — Hold Point 07.
Waste Disposal — Hold Point 07.
07Theory examination± 45 min+
Examination of theory by the trainer.
08On-site practicalSite dependent+
Site arrangements are coordinated before and after the practical, covering equipment, toolbox, product and the structure.
Practical demonstration by the trainer.
Trainee practical.
The duration is determined by site information.
ASSESSMENT & RECORDS
Demonstrate competence. Record successful completion.
The programme includes a theory examination and an on-site practical. Following successful course completion, accredited technician details are processed onto the Rustopak database.
Supporting instructions
Training works with the Rustopak ISO 9001:2015 aligned Technical Data Sheet and Quality Management Instructions.
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TESTING & ANALYSIS
Electrochemical Impedance Spectroscopy
Understanding the EIS measurement method and how its data is interpreted.
01
Measurement method
Electrochemical Impedance Spectroscopy (EIS) is a non-destructive, in-situ technique used to characterize corrosion by measuring the electrical impedance of a system across a wide frequency range, typically 100,000 to 0.01 Hz. The method applies a small alternating voltage and measures the resulting current to determine parameters such as polarization resistance, charge transfer resistance, and double-layer capacitance, which are used to calculate corrosion rates and analyze coating degradation.
02
Reading the data
Data is visualized using Nyquist or Bode plots and interpreted by fitting the spectra to Equivalent Electrical Circuits (EEC). These models separate different electrochemical processes, such as fast electron transfer at high frequencies and slow ion diffusion at low frequencies, allowing for the identification of mechanisms like pitting, passivation, and the effectiveness of protective coatings.
A FOCUSED TECHNICAL CONVERSATION
Meet with Rustopak
Arrange a private discussion about your project with Quentin. Include selected colleagues or technical allies so the right people can join the conversation.
Design preview · No booking, email or calendar invitation will be sent.
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Performance Evaluation of One-Coat Systems for New Steel Bridges
HRCSA performed well in accelerated laboratory and outdoor exposures, ranking second overall after the three-coat control. The report describes an alkaline coating designed for hydrophobic protection and strong ionic bonding with metal substrates, neutralising acidity and promoting passivity at the steel surface.
Laboratory method: similar to ASTM D5894-05, with an added freeze cycle.
