Intumescent Paint Products | Astro ISS-WI & WO Paint

>Trade Name: Astro ISS-WI & WO Paint

Intumescent Paint for Steel & Cast Iron

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Intumescent Paint for Steel and Cast Iron
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> Quick Overview


Intumescent Paint (Steel) Order Form Steel & Cast Iron Order Form

Telephone Astroflame 01329 844 500

Email Astroflame

PDF Data Sheets Download PDF Data Sheets

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Once you have filled in the required forms we will contact you to confirm all details (Monday-Friday).

> Product Description

Astro ISS-WI & WO is a water-based intumescent paint system providing fire resistance to structural steel and cast iron of up to 90 mins with a minimum number of coats. A compatible decorative overcoat system ensures the system will enhance the building’s architectural and design features. WIntumescent Paint for Steel and Cast Iron optimised for Intumescent Paint for Steel and Cast Iron & Intumescent Paint for Steel and Cast Iron shape steel and hollow bracing. WO optimised for hollow posts.

A compatible decorative overcoat system ensures the system will enhance the building’s architectural and design features. The range of topcoats are either water-based or 2010 compliant and safe to use in accordance with manufacturer’s instructions.

> How it works

The heat of a fire triggers a catalytic reaction, causing the expansion of an insulating char layer up to 50 times the paint thickness. This layer keeps the steel below its critical temperature, thus maintaining the structural integrity of the building.

Intumescent Paint for Steel and Cast Iron

> Fire testing

Product performance assessment is based upon UKAS/EGOLF Fire Test Laboratory Certification to BS 476 Part 21 - Fire Resistance to load bearing elements of structures. For certification and compliance with regulations the manufacturer will supply a Certificate of Supply on request.

> Preparation and Pretreatment

Steel and cast iron should be free from rust and millscale and primed with Astro HBP Primer to 75 microns DFT ( or alternative good quality anti-corrosive primer compatible with intumescent paints) in accordance with manufacturers instructions. Treat galvanised surfaces with “T” wash/Mordant solution & prime with zinc phosphate or other primer for steel. Astro HBP Primer may be left without further overcoating or decorated with appropriate conventional paint where no fire resistance is required.

> To Specify

We are happy to provide a quote please fill in our structural steel specification form to ensure we cover all aspects of your fire protection and decorative requirements in our quote.We accept any order size

Prior to application the contractor should contact the Astroflame Technical Department (see below) to obtain a basecoat application schedule.

For help please speak to the technical team on: >> Tel: 01329 844 500 or >> Email:

> Application

> Recoating

Brush/roller application

Spray application

> Spray Equipment

Airless Spray Pump

Use equipment recommended by manufacturer for the application of high viscosity intumescent paints.

Tip Size

Care should be taken to clean filters regularly. Cleaning should be undertaken with water.

> Colours, Finishes & Sizes

Colour Charts

> Composition

Intumescent compounds and resin binders, with high opacity pigments.

> VoC

The EU VoC limit for structural steel intumescent paints is 500 gm / litre. This product contains 398 gm / litre.

> Technical Advisory And Estimating Service

Our in-house estimators provide realistic, confidential guidance on project costings to contractors and quantity surveyors. They also provided expert advice and assistance with all aspects of specification and application.

> Application Conditions

> Installation

We have technical representatives who provide assistance in the selection and specification of the products on this site and should be consulted for exact installation and product suitability. Ensure an early engagement with ourselves, designers, main contractor and specialist installers before any installation. Other trades and/or manufacturers may need to be consulted. For in-depth information, specification and technical advice please call our Head Office on tel 01329 844 500 or email

> Maintenance

All interested parties, designer, specifier, main contractor and specialist installers should provide access to allow the fire stopping seals to be regularly inspected and maintained, as well as records kept of such maintenance at minimum periods of 12 months, as required by the Regulatory Reform Order, and repaired if necessary. Reference should be made to ASFP TGD 17 – Code of Practice for the Installation and Inspection of Fire Stopping.

> Competency

It is vital that those entrusted to design or install a fire stopping product have the necessary levels of competence to undertake the task professionally and thoroughly. The level of competency required will be commensurate with the expected complexity of the building. All designers must eliminate, reduce or control foreseeable risks that may arise during installation, construction or maintenance when preparing or modifying designs. Clients should ensure that the principal designer and principal contractor carry out their duties under CDM regulations. The ASFP foundation course in passive fire protection provides essential knowledge as part of demonstrating competency and understanding in this key fire protection specialism.

> Additional Notes

This product can only be supplied once the Steel Paint enquiry form has been completed and approved by the manufacturer: Click the following link to go to the Steel Paint Form: Steel & Cast Iron Order Form.

> Health and Safety

Astro ISS-WI & WO Paint is a low-odour, water-based coating, making it user and environmentally friendly. The range of topcoats are either water-based or 2010 compliant and safe to use in accordance with manufacturer’s instructions.

The product does not present any known health hazards during or after installation. Normal good industrial and personal hygiene practices should be observed. For further information on health and safety requirements please contact the technical team on: tel 01329 844 500 or email

> Data Sheet Downloads

Download and review the following available data sheets for this product.

Key Information:
  • PDS's are Product Data Sheets
  • SDS's are Safety Data Sheets
  • TDS's are Technical Data Sheets
  • INT's are Install Data Sheets
  • VID's are Video Files
  • DoP's are Declaration of Performance
  • CoC's are Certificate of Constancy of Performance
  • ETA's are European Technical Assessment Sheet
  • UL Documentation are UL - EU Certificate

> Delivery/Returns

For in-stock items orders received before 2pm (Monday-Friday) are generally dispatched for delivery on the following working day (Monday-Friday). All dates quoted for despatch are estimates only and are not guaranteed. We will endeavour to meet these dates but shall have no liability for any delay in despatch or delivery or any damage or loss occasioned thereby. We may deliver products pursuant to any order by instalments. If we are unable to deliver the goods for any reason,you will be contacted and you will not be obliged to pay for the goods which have not been delivered, you also have the option to cancel the goods that have been delivered, however we shall not be liable for any loss of income or profit which may have been caused by the delay or non delivery of goods.

For information about our returns policy please click here.

> Ask a Question

If you've got a question about this product or need some technical help get in touch with the Astroflame sales or technical team to discuss your requirements today. We are open Monday to Friday 8:00am to 5:30pm. You can always contact us on the following:

T: 01329 844 500


Web Page Last Modified: 19th April 2022

Data Sheets Downloads

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