The fire resistance of a steel component is its ability to withstand fire for a period of time under conditions of heat intensity.
Critical failure of steel occurs when the steel reaches 537°C (1,000°F). At this point, unprotected steel is reduced to 60% of its original strength, is prone to bend and deflect and the structural load stability and physical characteristics of steel is compromised.
Passive fire protection materials are designed to safeguard the structural integrity of steel under fire conditions and to maintain safe temperatures for a specified period of time.
The term “cementitious” often misleads design professionals to believe that the product contains cement, when in fact, most commercial density fireproofing products called “cementitious” do not. Ironically, most of the materials that were included in the “Sprayed Fiber” category actually do contain cement.
The industry has categorized SFRMs as either “Wet Spray” or “Dry Spray” materials. These terms better describe the manner in which the material is mixed, conveyed and applied.
Intumescent Fire Resistance Coatings are paint-like coatings that expand and char in a fire to insulate structural steel for up to 4-hours.
Thin Film Intumescent Coatings give Architects the ability to design using structural steel that can be decorative and aesthetically pleasing. Intumescent Coatings can be top coated to match their surroundings and allow steel to be left exposed to view while providing the necessary fire resistance ratings.
Type CB is ideally suited to protect structural steel in areas where there is limited clearance around perimeter walls, retrofit applications, seismic activity zones, moment connection framing and abatement projects where speed and dry application are required.
There is no need for tarping, masking, ventilating or heating of the work area since there is no minimum application temperature.
All products manufactured by Isolatek International contain no detectable asbestos. Ensure that all fire protection material suppliers provide independent test verification per EPA/600/R-93/116.
Depending upon thicknesses, environment conditions (i.e. temperature, air-flow, moisture, etc.), the period required for ISOLATEK® Spray-Applied Fire Resistive Materials (SFRMs) to fully cure is 14 to 28 days or more.
This assumes that ventilation is properly provided, particularly when spraying in enclosed areas such as basements, stairwells, shafts, and small rooms. A minimum of 4 complete air exchanges per hour is required until the material is dry.
Traditionally sprayed fireproofing is applied to bare steel. Gypsum based products tend to be less chemically aggressive than cement –based products. Where using cement based products, care must be taken when applying to specific primer type, such as alkyd primers. The primer coating must be identified and approved by Isolatek prior to fire protection.
Isolatek International has tested a wide array of paints/primers for compatibility with our fireproofing products to be used on wide flange beams and columns. A painted/primed beam or column must achieve a minimum average measurement of 80% and a minimum individual measurement of 50% of the manufacturer’s published bond strength on a clean uncoated 1/8 inch thick plate when tested in accordance with ASTM E736; the beam flange must not exceed 12 inches; the column flange must not exceed 16 inches; and the beams and column web must not exceed 16 inches. If the painted/primed members do not meet all of the above conditions, mechanical reinforcement (metal lath, steel studs) must be fastened to the substrate prior to fire protection.
Contact Isolatek Technical Services Department to determine compatibility of the primer used.
Isolatek has evaluated the compatibility of primers under laboratory conditions in accordance with ASTM D4541-95 (Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers). Results of our investigation indicate that certain primers are compatible with the intumescent basecoat, provided ISOLATEK Types WB 3, WB 4 or WB 5 are applied in accordance with our written application/installation instructions and primer manufacturer guidelines are followed. You can find a copy of our complete primer list by visiting our Product Information Section.
In following industry practice, the direct application of Intumescent Coatings over zinc-rich primers without the use of an approved barrier / tie coat is not recommended. When left exposed for long periods, zinc rich coatings may form a layer of zinc salts on the surface which may inhibit adhesion of the Intumescent Topcoat. Contact Isolatek International Technical Services for further information.
If a steel deck is to be painted/primed, it must be listed in the specified Underwriters Laboratories, Inc. (UL) Design as a classified painted deck for the particular fire protection product and certified for fire test compatibility by the deck manufacturer for the exact deck designation. ISOLATEK® Type EBS (mixed as an adhesive) is required on the underside of all roof deck.
The deck manufacturer must provide written confirmation that the paint/primer and the deck supplied to the project are those which are classified by UL. In addition, the deck must be listed in the UL roof assembly being utilized and Isolatek must confirm paint/primer adhesion compatibility.
ISOLATEK® Type CB is an ideal solution to painted roof decks and a wider variety of project sequencing issues that typically result in time and material patching. Include Type CB in all your SFRM base specifications.
For situations where the deck utilized on a project is painted, contact the deck manufacturer and/or Isolatek International to determine if the deck and paint is UL Classified.
ISOLATEK® Type M-II, high density SFRM, is also classified by UL as “Investigated for Exterior Use”.
Our ISOLATEK® Type WB 4 Intumescent Coating is a water-based, intumescent coating consisting of polyvinyl acetate resins and inorganic fillers for the fire protection of structural steel. ISOLATEK® Type WB 4, in conjunction with ISOLATEK® Type Topseal, is a water-based system investigated by UL for exterior applications. An additional protective topcoat, ISOLATEK Type Topseal, is applied over the ISOLATEK Intumescent coating in conjunction with an exterior finish coat. The topcoat material can be any colour match to provide a durable, decorative, architectural finish.
Surface coatings such as water-based latex, vinyl acrylic, urethane or chlorinated rubber coatings may be used as overspray on Types D-C/F, II, II HS, HP, 300, 300AC, 300ES, 300HS, 300N, 3000, 3000ES, 400AC, 400ES, 400, M-II, TG and M-II/P. If used, the coatings are intended for surface coloring only. Their application must be controlled so that the coatings do not saturate the Spray-Applied Fire Resistive Material (SFRM) and thus influence the bond between the SFRM and the steel substrate. Unless specifically indicated above, these systems have not been investigated for exterior use. The flame spread index of the surface coating shall be less than 200 as determined by the test method in ANSI/UL 723 (ASTM E84 and NFPA 255). Surface Burning Classifications are contained in the Building Materials Directory.
In areas where there is expected to be a greater than normal amount of air movement such as elevator shafts or areas adjacent to exhaust fans, it is recommended that our ISOLATEK® Type EBS be applied as a sealer. Otherwise, a sealer or topcoat is considered optional, as we do not require a sealer in maintaining the fire rating or physical properties of the SFRM.
Thickness of the fire protection material is dependent upon the assembly in which it is being applied. The following is a partial list of the basic information required by the estimator to determine the proper Underwriters Laboratories (UL) assembly or fire test assessment.
• Type of deck and depth of metal deck
• Type of topping on deck (i.e. concrete or insulation type and thickness)
• Beam sizes supporting deck
• Type of column and column sizes
• Hourly rating required
Once an assembly is determined and a UL Design is selected, the design will list the proper thicknesses required.
It is an industry standard for Spray-Applied Fire Resistive Materials (SFRMs) that the temperature at the job site must be greater than 4°C (40°F). A minimum substrate and ambient temperature of 4°C (40°F) shall be maintained prior to, during, and for a minimum of 24 hours after the application.
For ISOLATEK® Intumescent Coatings, the minimum ambient temperature must be between 10°C (50°F) and 38°C (100°F). A minimum substrate and ambient temperature of 10°C (50°F) shall be maintained prior to, during and a minimum of 72 hours after application.
If necessary, tarp enclosures and temporary heat may be utilized to maintain the proper temperature and humidity levels in the application areas.
These are the standards called out and accepted by the Association of the Wall and Ceiling Industries – International (AWCI) as wells as The National Fireproofing Contractors Association (NFCA).
You can obtain Technical Letters, Submittal Information and Engineering Judgments by contacting Isolatek Technical Services via our Hotline at 973-347-1200 (Option 1), Fax at 973-347-6730 or email at email@example.com.
All Isolatek International technical related letters and documentation must be issued through the Isolatek International Corporate Technical Services Department.