Most businesses invest heavily in locks, alarms, CCTV and staff ID badges, then assume the job is done. But security equipment only works if the people and processes around it work too. A propped-open fire door, a friendly receptionist who doesn’t want to seem rude, or a contractor nobody thinks to question can undo thousands of pounds of security spending in seconds.
The only reliable way to know whether your defences hold up is to test them the way a real intruder would. That is exactly what a physical penetration test does.
At Assist Investigations, our team of former police officers carries out authorised physical penetration tests for businesses across West London, Windsor, Berkshire and throughout the UK. In this article, we explain what the service involves, what we look at, and why more organisations are choosing to put their security to the test before someone else does.
What is physical penetration testing?
Physical penetration testing (sometimes called a physical security assessment or “red team” exercise) is an authorised, controlled attempt to gain access to your premises, restricted areas or sensitive information. It is carried out with your written permission, to an agreed scope, by professionals whose only aim is to find the gaps before a criminal does.
Where a security risk assessment reviews your measures on paper and on a walk-round, a penetration test asks a harder question: does it actually work under pressure? We don’t just note that you have an access control system. We find out whether it can be bypassed, whether staff challenge unfamiliar faces, and whether anyone notices when something goes wrong.
The result is an honest, evidence-based picture of your real-world security, not the one written in the policy manual.
What do we test?
Every engagement is tailored to your site and your concerns, but most tests look at a combination of the following:
- Perimeter security – fencing, gates, car parks, loading bays and the routes someone could use to approach unseen.
- Entry points – main entrances, fire exits, side doors and windows, and whether they are properly secured and monitored.
- Access control – how well card readers, keypads, turnstiles and visitor systems stop unauthorised people getting through.
- Tailgating and piggybacking – whether an intruder can simply follow a member of staff through a secure door.
- Social engineering – whether staff can be persuaded to grant access or share information by someone posing as a contractor, courier, job applicant or colleague.
- Reception and visitor procedures – how visitors are signed in, identified, badged and escorted.
- CCTV and alarm response – whether cameras cover the right areas, whether anyone is watching, and how quickly an intrusion is noticed and acted on.
- Sensitive areas and information – server rooms, stock rooms, executive offices, unlocked screens, confidential paperwork and what is left in bins.
As we work, we gather photographic and written evidence of each finding, so you can see exactly what happened and where.
How a physical penetration test works
We follow a clear, structured process so you stay in control from start to finish.
- Initial consultation – We discuss your premises, your concerns and what you want to achieve. This might be testing a single entrance, a whole site, or how staff respond to a specific scenario.
- Scoping and authorisation – We agree exactly what is in and out of scope, the dates, the methods we may use and who within your organisation knows about the test. Everything is confirmed in writing, and our team carries a signed letter of authorisation throughout.
- Reconnaissance – Drawing on our surveillance experience, we observe your site as an outsider would: shift patterns, staff movements, deliveries, smoking areas and anything visible from public spaces or online.
- The test – We attempt to gain access in line with the agreed scope, recording evidence as we go. If we reach a target area, we document it and leave without causing damage or taking anything of value.
- Debrief – Where appropriate, we speak with staff afterwards. The aim is learning, not catching anyone out.
- Report and recommendations – You receive a clear, written report setting out what we tested, what we found, the evidence, the level of risk and practical, proportionate steps to fix each issue.
We can also return after improvements have been made to re-test and confirm the gaps are closed.
Safe, lawful and professional
A physical penetration test should never put your people, your property or your reputation at risk. Our safeguards include:
- Written authorisation from someone with the authority to grant it, carried by our team at all times.
- A clearly agreed scope, including any areas, people or methods that are off-limits.
- Emergency contacts on call throughout, so any challenge from staff, security or police can be resolved quickly.
- No damage and no theft – we prove access, document it and leave things as we found them.
- Strict confidentiality – findings are shared only with the people you nominate, and evidence is handled in line with data protection law.
With sixteen years of policing experience behind our founder, Erika Morris, and a team of former officers, we understand the legal boundaries, the importance of evidence, and how to handle a situation calmly if a test is challenged.
Who is physical penetration testing for?
Any organisation with something worth protecting can benefit, but we most often work with:
- Offices and corporate headquarters holding confidential data, client information or intellectual property.
- Retail and hospitality venues concerned about theft, staff-only areas and public safety.
- Warehouses, logistics and industrial sites with high-value stock and busy delivery routes.
- Data centres and IT suites where physical access could lead to a serious data breach.
- Schools, healthcare and care settings where safeguarding depends on controlling who comes in.
- Venues and event organisers preparing for Martyn’s Law.
- Landlords and facilities managers responsible for shared or multi-tenant buildings.
It is also valuable after a security incident, a change of premises, a new access control system or a period of staff turnover – any time you need confidence that your security works as intended.
Frequently asked questions
Will my staff know the test is happening? That is your choice. Most clients tell only one or two senior contacts, so we see how staff respond naturally. We agree this during scoping.
Is it legal? Yes, when it is properly authorised. We only test with written permission from someone entitled to give it, and within a scope agreed in advance.
What if a member of staff or the police challenges your team? That is often a positive finding. Our team stops, identifies themselves, produces the authorisation letter and contacts your nominated emergency contact to verify.
Will staff get into trouble? We strongly recommend using findings to improve training and procedures, not to discipline individuals. Most weaknesses come from processes, not people.
How long does it take? It depends on the size of the site and the scope. A single-entrance test can take a day, while a multi-site engagement may run over several weeks. We will give you a clear timeline in your proposal.
What do I get at the end? A confidential written report with evidence, risk ratings and practical recommendations, plus a debrief to talk it through.
Put your security to the test
The best time to discover a weakness is before someone with bad intentions does. If you want honest answers about how secure your premises really are, speak to our team for a confidential, no-obligation conversation.
Call 07476 938 795 or 01753 905026 Email services@assistinvestigations.co.uk Or book an initial consultation