Professional fibre optic testing and certification

Fibre optic testing and certification provide documented proof that a fibre link performs to specification. Whether you are commissioning a new fibre optic installation, diagnosing a fault, or evidencing compliance for an audit or handover, certified test results are the difference between assuming a network works and proving it does.

As members of the Fibre Optic Industry Association, ACCL’s engineers test with calibrated equipment and issue full certification reports covering insertion loss, reflectance, and length for every link, giving you a complete, auditable record of network performance.

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Andrew Matthews profile picture
Andrew Matthews
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We commissioned a Wi-Fi survey and installation of new fibre and Cat6 cabling to support a new Wi-Fi installation from Accl in July and August of 2026. ACCL were superb from start to finish. We cannot fault the quality of the work and we received great advice on our project. Very satisfied customer!
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Brigt Valland
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Very professional company, good at understanding our need and efficient delivery of new building network- and WIFI infrastructure. An extra star for making it easy for me to "remote" organize this from Norway.
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Siobhan Codd
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We used ACCL for a full WiFi and network install at our Old Street office and are very pleased with the result. They supplied and installed seven Ubiquiti WiFi access points, a UniFi Dream Machine, a 24 port Layer 3 Ubiquiti switch, and ran new Cat6A Leviton cabling with two ports to every AP. The whole job was neat, well planned and done to a very high standard. The coverage across the office is excellent and it looks pretty cool too! Would happily recommend them to anyone needing cabling or network infrastructure done properly.
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Mark Cooper profile picture
Mark Cooper
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An excellent service from start to finish! The ACCL team installed our new network cabling, the foundation in readiness for supplying and installing a new IP CCTV camera system, professionally and efficiently. They were punctual, knowledgeable, and took the time to ensure everything was installed neatly and working perfectly. Their attention to detail and customer service were outstanding. I very much appreciate the initial project management and upfront planning, which combined to secure a successful delivery. I would highly recommend them to anyone looking for reliable network cabling or CCTV installation. Thank you for a fantastic job.
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Mohammed Alhashimi
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I would like to express my sincere appreciation to Wayne and his team for the excellent work they carried out. From start to finish, they were professional, reliable, efficient, and clearly took great pride in delivering a high standard of service. They were professional, efficient, and paid great attention to detail, ensuring everything was neat, clearly labelled, well organised, and completed to a very high standard. The end result was clean, structured, and exactly what we needed. Wayne and his team were reliable, courteous, and clearly committed to doing the job properly rather than simply getting it done. I would highly recommend them to anyone looking for professional cabling work and a team that genuinely takes pride in the quality of their finish.
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Laurence Rutter
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So easy to deal with! Great price and great guys! Did exactly what they agreed, on time and in budget. Would thoroughly recommend them to anyone.
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AlonMel Music
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Wayne and team did an excellent job tidying our office data cabinet over the weekend. Professional, clean work—they went above and beyond with cable management and even relocated the router. Communication was impeccable throughout. Highly recommend.
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Amritpal Singh profile picture
Amritpal Singh
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"Outstanding service from ACCL. They did an incredible job with our networking and data cabling. The setup is neat, professional, and works perfectly. Extremely knowledgeable and easy to work with. I’ll definitely be using them for all our future IT needs!" Huge Shout to Wayne Connors and David Little for managing this.
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Andy Dawson profile picture
Andy Dawson
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We've worked with Wayne, David and the ACCL team for a number of years on projects throughout London. One of very few suppliers that we never have to question their proposal on detail or price, everything is clear, transparent and fair. Projects are always completed on time and there are never any costly surprises which we had previously experienced from other suppliers. They all have a vast knowledge on anything fibre optic cabling, copper cabling or wifi. ACCL is now the only data cabling company in our phone book. Highly recommended.
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Indrajit Shah
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Great service and communication. Will definitely be contacting Wayne and ACCL for future projects.
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Our fibre optic testing services

We test to recognised standards and report every result. Our testing covers new installations, fault finding, and periodic verification of existing infrastructure.

  • OTDR testing

    Optical Time-Domain Reflectometer testing that maps the entire fibre run, pinpointing splices, connectors, bends, and faults by distance. Carried out bi-directionally and at every relevant wavelength for an accurate, complete trace.

  • Insertion loss (OLTS) testing

    Optical Loss Test Set measurement of end-to-end attenuation against the link loss budget, confirming each link meets its required performance threshold.

  • Fault diagnosis & location

    Rapid identification and precise location of breaks, high-loss joints, and degradation, feeding directly into our fibre optic repair service.

  • Certification & reporting

    Full documented certification per link, ready for warranty, compliance, and project handover. Results delivered in a clear, auditable format.

  • Pre- and post-installation testing

    Verification before, during, and after installation so issues are caught early and the finished network is signed off with confidence.

  • Annual & periodic verification

    Scheduled re-testing of critical links to detect degradation before it causes downtime, with equipment kept on a regular calibration cycle.

Why certified testing matters

Uncertified fibre is a liability. Without documented test results you cannot prove a link meets standard, support a warranty claim, or satisfy an auditor, and intermittent faults can go undetected until they cause an outage. Certified testing gives you measured evidence of performance, a baseline to compare against in future, and the documentation required for compliance. It is the final, essential step that turns a fibre installation into a verified asset.

Trusted on critical infrastructure

Our engineers have delivered fibre testing and certification across demanding commercial and financial environments, including major banking, exchange, transport infrastructure and data centre environments where accuracy and documentation are non-negotiable. The same rigour applies to every project, from a single link to a full campus, and pairs naturally with our fibre splicing and termination work.

Get in touch today

Have a no-obligation chat with one of our data cabling experts, who can recommend a solution to suit your requirements and budget.

What our clients think

  • We would like to take this opportunity to thank, You, Wayne and the team for such an excellent and professional implementation.

    The organisation was fantastic and the way you worked within the building was great 😊 the business users did not even know what was going on in the building 😊 We would definitely not hesitate to use you guys again.

    Wise Music Group

    Wise Music Group
  • As the client I can only say thanks and its an amazing piece of work by all involved. Believe me that the work to coordinate this work around other issues was challenging but Wayne and ACCL were great.

    TUI / Scott Ronan

    TUI / Scott Ronan

Need your fibre tested and certified?

Whether you are signing off a new installation or diagnosing a fault, our FIA-certified engineers provide accurate testing and full certification. Contact us to arrange an attendance.

Frequently Asked Questions – (FAQs)

What is OTDR testing?

OTDR (Optical Time-Domain Reflectometer) testing sends light along the fibre and measures the reflections to map the whole run, locating splices, connectors, bends, and faults by distance. We test bi-directionally and at every relevant wavelength for an accurate, complete trace.

What is the difference between OTDR and insertion-loss testing?

OTDR maps events along the fibre and locates faults; insertion-loss (OLTS) testing measures total end-to-end attenuation against the link loss budget. A full certification uses both.

Do you provide a certification report?

Yes. We issue documented certification per link covering insertion loss, reflectance, and length, in a clear, auditable format suitable for warranty, compliance, and handover.

Why do I need my fibre certified?

Certification proves each link meets standard, supports warranty and compliance, provides a performance baseline, and catches faults before they cause downtime.

Can you test an existing fibre network?

Yes — we carry out periodic and annual verification of existing links to detect degradation early, as well as testing new installations.

Is your test equipment calibrated?

Yes. Our test equipment is kept on a regular calibration cycle, so results are accurate and defensible.