February 24, 2014
Typical Corrosion Protection on Exposed Steel Structures Forgets About Fire Hazards
by Hinman Team
There are typical specifications used for exposed steel structures in marine environments. These specifications usually include coating systems that provide protection against corrosion. A typical coating system has the following layers (www.nepcoat.org1):
1. Zinc Primer
2. Epoxy/Urethane Intermediate Layer
3. Polyurethane Topcoat
As a structural fire consultant, the polyurethane topcoat jumps out at us as a fire hazard. It’s basically painting fuel directly onto the steel elements!
We did a little bit of research and contacted the Carboline Company2. We found that while this NEPCOAT qualified products list does not explicitly include fire protection coating systems, they have a NEPCOAT qualified system that includes both corrosion protection and fire protection (intumescent paint) layers as follows:
1. Carbozinc 859 Primer
2. ThermoLag 3000 Series Intumescent Layer
3. Carbomastic 94 Intermediate Layer
4. Carbothane 133 LH Topcoat
If you are working on an exposed steel structure that have potential fuel (e.g. fuel tanks, tanker truck traffic, and/or other types of fuel storage) within proximity of the primary structural elements, look through your Division 7 and Division 9 (Thermal and Moisture Protection and Finishes divisions, per CSI Masterformat) specifications and consider coating systems to protect from both hazards. Better yet, call us and we are more than happy to help you with your considerations by modeling your hazards and reviewing your specifications.
1NEPCOAT (NorthEast Protective COATing committee) is referenced by typical specifications of transportation agencies in the US North-East region. According to a representative of the Carboline Company, their NEPCOAT qualified corrosion and fire protection system, while not listed, is being used on many transportation projects in the region. www.nepcoat.com
2Carboline Company is a protective coatings provider who has been generous enough to discuss the above topic with us. www.carboline.com