Important Considerations When Specifying and Inspecting Fireproofing Materials Applied to Steel Structures

Abstract

When designing steel frame structures that can withstand the effects of fire, it is important that structural engineer consider a number of factors and recommend products that will perform adequately in the expected building environment. Simply quoting an hourly rate and leaving it to the contractor to adopt the least expensive solution is irresponsible and can result in unsafe materials being used. When inspecting the application of the fireproofing on site the engineer needs to be aware of the limitations of the applied materials. It is important to remember that fireproofing materials are tested in controlled laboratory environments which may not compare to a real site. The following guidelines explain some factors that engineers should consider when specifying appropriate fireproofing materials and inspecting their application on site: 1. Is the steel internal or external? If it is internal, will it be subject to areas of high humidity, freezing and thawing cycles, corrosive atmospheres, salt spray, etc.? For external applications, or those internal applications where the material may be subject to adverse environmental conditions, the specified products should have passed relevant environmental testing procedures as per UL 1709 or ASTM E 1529 . It should be noted that UL 263 or ASTM E 119 or NFPA 251 do not require environmental testing for products. 2. What ambient environmental or climatic conditions are expected when fireproofing is applied? Most fireproofing products require a stringent range of temperatures and humidity levels to be maintained for successful and approved application. The engineer should specify products whose limitations are unlikely to compromise the application on site as per the manufacturer’s application specification. During construction, the engineer should monitor the site conditions to ensure they are within the limits specified for the product used. 3. Will appropriate surface preparation be possible in the building site environment? Most fireproofing materials require careful surface preparation and the absence of dust, dirt and oil during the application process; some also require priming. If it is not reasonable to expect that these conditions will be achieved on the proposed site, then some preparation and application may need to be done offsite. During application, the engineer should monitor these site conditions to ensure they are in accordance with the manufacturer’s recommendations. It