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Preliminary UXO Risk Assessment 2

Preliminary UXO Risk Assessment_

A Preliminary UXO Risk Assessment is a crucial early step in identifying the risk of unexploded ordnance on your project site. At Brimstone UXO, we combine in-depth historical research with extensive industry expertise to deliver fast, reliable, site-specific assessments. With a typical turnaround of 24 to 48-hours, our assessments are the fastest and most cost-effective way to identify or discount potential UXO risks and ensure safe project planning.

Not sure if you need a Preliminary UXO Risk Assessment or a more detailed investigation? Get in touch with our team for expert advice.

Example of imagery used in a Preliminary UXO Risk Assessment.

What is a Preliminary UXO Risk Assessment_

A Preliminary UXO Risk Assessment is a desktop-based study that evaluates whether a site may be affected by historic military activity. Sometimes referred to as a Stage 1 Risk Assessment or a PRA, this is typically the first step for construction or development projects aiming to mitigate UXO risks.

Our experienced researchers investigate the military history of your site and surrounding area, using high-quality sources to determine whether there’s a credible risk of encountering UXO. The goal is to establish whether a more detailed assessment is required before ground works begin.

(Please note, if your site is on or near former military land, a Detailed UXO Risk Assessment may be more appropriate.)

A damaged building

How we create your Preliminary UXO Risk Assessment_

Every risk assessment from Brimstone is tailored to your site and carried out by experts. Here’s how we create our reports:

Our research team have spent the last eight years refining our processes and perfecting our risk assessments to ensure we exceed client expectations. Our researchers are passionate about historical research and all hold degrees in related fields.

We consult a wide range of primary and secondary data sources, including bomb maps, bomb damage records, historical aerial photography, OS mapping, and written military documentation. These are used to inform a clear, evidence-based assessment.

Once data has been gathered, we assess the likelihood and potential impact of UXO on your site. This includes evaluating the type of military activity, target significance, and post-war development that may influence the presence of UXO.

We pride ourselves on our thoroughness, accuracy, and reliability. To ensure this, every risk assessment undergoes an internal quality assurance check before being issued to our client.

You’ll receive a bespoke risk assessment report outlining our findings and a clear recommendation: either that no further action is needed, or that a Detailed UXO Risk Assessment should be undertaken.

Planes dropping bombs

Why Order a Preliminary UXO Risk Assessment_

This type of assessment is essential for understanding early-stage UXO risks and ensuring you meet your duty of care. Key benefits include:

Unexploded ordnance is found in locations across the UK – including areas with no obvious military history. A UXO risk assessment helps ensure you are not unknowingly putting people at risk.

There are no specific UK laws requiring a UXO risk assessment, but developers must meet legal obligations under the Health and Safety at Work Act 1974 and the CDM Regulations 2015.

CIRIA C681 is the recognised guidance document for managing UXO risk. It sets out a four-stage approach: Preliminary UXO Risk Assessment, Detailed UXO Risk Assessment, Risk Mitigation, and Implementation. We follow this best-practice guidance in every project.

Identifying risks at the planning stage helps prevent costly delays and reactive mitigation later. Most sites in the UK are assessed as low risk – so this quick, affordable step can bring peace of mind and avoid unnecessary disruption.

Example of imagery used in a UXO Risk Assessment.

What to Expect From Your Risk Assessment Results_

Following completion of your Preliminary UXO Risk Assessment, you’ll receive a 2 to 4-page bespoke report summarising the research findings, UXO risk rating, and next steps.

If further research is required, we’ll recommend a Detailed UXO Risk Assessment and explain why. If not, the report will confirm that the UXO risk has been reduced to As Low As Reasonably Practicable (ALARP), and no further UXO risk mitigation is needed.

If a detailed assessment is required, we deduct the cost of the preliminary report from the total, saving you money and ensuring continuity.

Brimstone Mountain vector with dots

Order Your Preliminary UXO Risk Assessment_

Ready to get started? Ordering a UXO risk assessment from Brimstone is quick and straightforward.

To ensure we tailor our assessment to your exact requirements and timeline, we’ll need a few key details from you. These include the site location, the redline boundary, and an overview of the proposed works.

Once we have this information, we’ll deliver your report within 24 to 48-hours, providing you with the clarity you need to proceed safely and confidently with your project.

Don’t leave UXO risk to chance. Click below to order your Preliminary UXO Risk Assessment today.