What is the difference between factory-applied and field-applied fireproofing?

• A. Field-applied uses a different material than factory-applied.
• B. Factory-applied is applied at the factory and typically sent to site; field-applied is installed on site; QA/QC differs.
• C. Both are installed at the factory.
• D. Factory-applied is installed on site; field-applied is at the factory

Answer: (B)

The key difference is where the fireproofing is installed and how quality checks are handled. Factory-applied fireproofing is applied in a controlled factory setting, then shipped to the job site as a prepared product. Because the work happens in a controlled environment, thickness, density, adhesion, and curing are verified in the shop, and QA/QC documentation accompanies the material. Field-applied fireproofing is installed directly on the structural elements at the project site, so on-site conditions—surface preparation, substrate compatibility, ambient temperature and humidity, thickness tolerance, curing time, and protection after application—drive the QA/QC process and inspections. The material used can be the same or similar, but the critical distinction is the location of application and the associated QA/QC requirements.