Firesteel 60WB
Intumescent Coating For Structural Steelwork

• Waterborne intumescent coating designed for internal structural steelwork
• Provides 30 and 60 minutes resistance 
• Tested in accordance with BS476:Part21 1987 by Warrington Fire
• Highly competitive loadings
• Easy application properties
• Minimal VOC's - EPA Compliant and 'environmentally friendly'
• Topseal are not required however where a finish colour has been specified we can supply a suitable topseal available in a wide range of BS4800 or RAL colours

Firesteel 60WB - Loading Tables (DFT)

Guidance Notes:

Firesteel 60WB is a waterborne intumescent coating designed for structural steelwork such as beams, columns and hollow sections.  

The thickness of an intumescent coating is dependent on the steel section used. For calculation of DFT (dry film thickness) a factor called HP/A (heated perimeter divided by cross sectional area) is used (click on the Firesteel 60WB loading table above to view the DFT figures). Intumescent coatings are applied as an intermediate coat in a coating system (primer, intermediate and top/finish coat if required).  NB: HP/A is generally used with British testing and A/V in European testing, however, the principles are the same and both are accepted methods of calculating the steel section factor.

The rate increase in temperature of a steel cross-section is determined by the ratio of the heated surface area (A) to the Volume (V).  This ratio A/V, has units of m-1 and is known as the “Section Factor”.  Steel members with low Section Factors will heat up more slowly.  A steel section with a large surface area (A) will receive more heat than one with a smaller surface area.  Also, the greater the volume (V) of the section, the greater the heat sink.  Therefore, a small thick section will be slower to increase in temperature than a large thin one.  The Section Factor (A/V or HP/A) is thus a measure of the rate at which a section will heat up in a fire.  The higher the value of the Section Factor the greater the protection thickness required.

Steel Preparation & Primers:

A primer is used as a preparatory coating put on the steel before applying the intumescent paint and acts to provide corrosion protection.  Priming ensures better adhesion of the intumecent paint to the surface, increases its durability, and provides additional protection for the material being painted and is always recommended.

A primer designed for steel is still highly recommended if a part is to be exposed to moisture.  Once water seeps through to the bare metal, oxidation will begin (plain steel will simply rust). Metal primers might contain additional materials to protect against corrosion, such as sacrificial zinc.

Metal hydroxides/oxides do not provide a solid surface for the paint to adhere to and paint will come off in large flakes. Using a primer will provide extra insurance against such a scenario. An additional reason for using a primer on the steel could be the poor condition of the surface.  A steel part can be rusty, for example and should be prepared to the Swedish Standard 2.5 in accordance with BS7079 Part A1.

Firesteel 60WB should be applied to clean, dry and primed steels.  Extensive primer compatibility tests have been undertaken on single and two pack products commercially available.  Bituminous and chlorinated rubber primers are unsuitable because of their poor performance in fire conditions.  Zinc rich primers require a tie coat before application of Firesteel 60WB. If you are ever unsure of the primer and its compatibility then please send us the details of the primer and we will confirm compatibility.  

Application Conditions 

Firesteel 60WB is a waterborne product but despite this, has a high tolerance of site conditions.  The product is fast to dry even in low air movement conditions.  Air movement will speed up the drying times.  Coated surfaces must be protected from exposure to water. 

It is important to ensure the minimum temperature at the time of application is at least 5ºC on a rising thermometer with an RH of 80% or lower.  Steel temperature should be at least 3ºC above dew point.  Check the steel by touch to see if there is any condensation or water on it.  If there is, stop and wait for the steel to warm up.  

Application

Firesteel 60WB may be applied by brush, roller or spray.  It should not be diluted.  Mechanically stir before use, this will slightly loosen the product.  

Maximum wet application per coat:

By brush 0.5mm (500 microns) using a laying technique.
By spray 1.2mm (1200 microns).  

A wet film gauge is provided to monitor paint thickness during application.  Press the teeth of the gauge into the wet paint, holding the gauge at right angles to the surface.  The last wet tooth denotes the wet film thickness in microns. Keep the gauge clean and do not let paint dry on it.  To check dry film thickness ensure the paint surface to be measured is hard dry.  This can be checked by trying to make an impression in the paint film.  Use a magnetic gauge such as an Elcometer (an electronic instrument).  Subtract primer film thickness from reading and top seal if used.  

Drying Time

In still air conditions the following drying times can be achieved with an RH of 50% by spray application.

600 Microns Wet Film 

​1200 Microns Wet Film

Product Data

Can we help?

If you would like to send us your steel sizes we would be happy to calculate the loadings required using Firesteel 60WB.  We would recommend that intumescent coatings are carried out by an approved applicator.

All orders are usually despatched within 24 hours of receiving cleared payment (Mon–Fri).

The above information is based on current test data, health and safety information and application instructions supplied by our suppliers and manufacturers of the products. It is supplied for guidance and to the best of our knowledge is true and accurate. Customers should satisfy themselves to the suitability of the products in its intended use and no guarantee is given or implied as the conditions of actual use are beyond our control. If in doubt the customer should consult the designer of the product or the local building control. 

Fire Stopping Shop, disclaim any liability for loss, damage or other expense which may arise from the use of this information, data or products refereed to and reserve the right to amend or change any details without notice. This statement does not affect your statuary rights.