Nullifire explains the principles to engineering judgements

Ryan Gerrard / 23 September 2022
Engineering Judgements (EJ’s), or Technical Evaluations, as they are commonly referred to, is a drawing or group of drawings generated by our in-house expert technical team for a customer’s specific jobsite application. They are recommended as a solution when a contractors jobsite application deviates from third-party tested fire stopping designs or systems.

With contractors around the UK and Ireland, consistently encountering unique jobsite conditions requiring new penetrations through fire-rated areas, Nullifire recognises the industry need for engineering judgements however these will only be presented as a recommended solution when job site conditions deviate from a tested design/solution and site cannot/refuse to adjust conditions to bring them in line with testing.

Following PFPF guidelines wherever possible, engineering judgements are fire stopping proposals created by a qualified member of the Nullifire team based of pre-existing third party tested and approved systems. The expert’s opinion does not consider fire engineering or fire science – it is purely formulated by historical test data and professional judgement. 

Acquiring an engineering judgement from Nullifire:

1.    Consultation with Nullifire Technical Team

A quick and easy process, our consultations will identify the need for engineering judgements. During the consultation, our team will be able to let you know if we have sufficient data to generate an engineering judgement. 

2.    EJ Generation 

After consultation, our in-house experts will draw an engineering judgement, based on historical test data and professional judgement. The EJ will include a description of scope, and rational behind the EJ. The engineering judgements issued will always be based upon a minimum of one test, however most will be based upon multiple third party tested designs/solutions. 

3.    Issue EJ and relevant certification to contractor 

Upon issue, the contractor requesting the EJ will receive the proposed solution and supporting certification. Our technical team are on hand to talk contractors through the engineering judgements and the rationale behind the judgement if required. Contractors will also be talked through the assess, accept, and build and burn process. 

4.    Accept It, if refused assess It, build, and burn It 

This is a critical step in the process of issuing an engineering judgement. All contractors and site should accept the engineering judgement and associated liabilities prior to install. If not accepted, it is a requirement that the EJ undergoes a desktop assessment. Alternate option would be that the contractor or client seeks to have the engineering judgement tested by a third-party, UKAS accredited test house. 

As best practice, Nullifire stores all engineering judgements completed for contractors. These are regularly reviewed by our in-house team and commonalties amongst requests are identified and often scoped into our test program. 

For more information on Nullifire Fire Stopping, please contact 

Part of the Construction Products Group portfolio of brands, and previously available in the UK under the Firetherm name, Nullifire products are used extensively across built environments, with the benefit of highly knowledgeable technical support and service, stringent manufacturing processes and testing regimes, to ensure the ultimate peace of mind in the specification process.

Find out more about Nullifire here.