Anyone who has spent time in the world of firestopping has undoubtedly dealt with engineering judgements or “EJs” as they are commonly referred to in the field.
What exactly is an engineering judgement?
To answer that question, it is critical to first understand the difference between a listed firestop assembly and a firestopping product. Most people think firestopping products carry the fire resistance rating. This is not true. All major building codes call for listed firestop assemblies where there are penetrating items and/or joints in fire resistance rated walls or floors. The assembly consists of the wall or floor that is being penetrated, the penetrating item(s), the size of the opening and arrangement of the penetrating item in that opening, and the firestopping materials that protect the opening. All of these components are outlined in the listing of the firestop assembly. Each listed firestop assembly has actually been fire tested in this specific configuration and all of these components must be installed correctly in the field for the system to hold the specified fire rating.
Even though most major firestopping manufacturers have over 1,000 listed firestop assemblies in their catalogs, there are inevitably field conditions which do not match one of the listed firestop assemblies available. This is where an engineering judgment can be a very useful and effective solution in lieu of incurring the cost of an expensive fire test. An engineering judgement is an evaluation of the anticipated performance of a proposed firestop assembly that has not been fire tested; engineering judgements are based on the performance of listed firestop assemblies and engineering principles.
Are engineering judgements permitted by the building code?
Section 104.11 of the International Building Code, 2015 Edition permits the use of alternative materials, designs and methods of construction where sufficient data is submitted to the building official to illustrate that an equivalent level of safety is maintained.
What typically constitutes a sufficient level of information to provide to a building official to substantiate an engineering judgment?
The International Firestop Council has published guidelines for evaluating engineering judgements (which can be found by clicking here). These guidelines are extremely helpful to building and fire officials who need to perform these evaluations. Some of the critical information contained in the guidelines are the following:
- Include the date the EJ was issued, who wrote the EJ, and their contact information;
- Reference the tested firestop assemblies the EJ was based on;
- Identify the specific job name, project location, and firm the EJ is being issued to. Note: EJs should not be carried job to job since they are a snap shot in time evaluation of a specific installation.;
- Identify any conditions that are outside the EJ evaluation.
Anyone writing an EJ should have knowledge of the fire testing of the listed assemblies the EJ is based upon and be able to use engineering and mathematical principles to interpolate performance. For this reason, a vast majority are written by the firestop manufacturers technical service department engineers.
A common issue we experience in the field when performing special inspections for firestopping assemblies per ASTM E2174 and ASTM E2393 (for more information on special inspection requirements click here) is that the engineering judgements are not being submitted to the building official for approval and are simply being recorded in a project submittal log. Upon receiving these EJs during inspections, we often encounter notes that make statements such as “Cold Smoke Seal Only”, “May not provide T Rating per UL 2079” and “Dependent upon performance of fire rated beam in fire conditions”. These statements should be evaluated carefully when looking at the appropriateness of the application relative to the minimum code requirements that apply. Unfortunately, far too often details with these types of notes get installed without any review and discussion on the merits of the assembly.
The frequency of special inspections for firestopping assemblies is increasing dramatically due to a requirement, first adopted in the 2012 IBC, that requires special inspections in all new firestopping installations in high rise buildings and other “high risk occupancies” such as: hospitals, first responder occupancies, large assembly occupancies, and college and university buildings with more than 500 occupants. The special inspector is not authorized per the ASTM standards to approve engineering judgements. That power is still held by the building official. However, the special inspector should be evaluating if the engineering judgements provided meet the minimum code requirements for where they are being applied and if there are obvious issues, discuss them with the approving authority.
Code Red Consultants employs over 20 fire protection engineers and has 6 staff members that are certified third party firestop inspectors per the IFC. Please do not hesitate to contact if you are in need of firestopping special inspectors or further education on the topic.