NPORS CAT & Genny Training (N304): What to Expect 2026

When You Book Multiple Courses.

Striking a live cable or a pressurised gas main during excavation is one of the most dangerous mistakes a groundworker can make. It is also one of the most avoidable. The NPORS N304 Cable Avoidance Tool course teaches operatives exactly how to use a CAT and Genny properly, so buried services are located and marked before a spade ever touches the ground.

This guide explains what the NPORS N304 course covers, who needs it, how the assessment works, and how to book training through Target Zero.

What is the NPORS CAT and Genny (N304) course?

The NPORS N304 Cable Avoidance Tool course is a one-day qualification that trains operatives to detect and mark underground services using a Cable Avoidance Tool (CAT) and Signal Generator (Genny). The course combines theory and practical assessment, and leads to a recognised NPORS Operator card valid across construction, utilities, and civil engineering sites.

The CAT detects signals given off by buried services such as power cables, telecoms lines, and metal pipes. The Genny injects a traceable signal into a known service so the CAT can follow its route. Used together, the two tools build a reliable map of what lies below a dig site before any breaking ground takes place.

Who needs NPORS CAT and Genny training?

Any operative who digs, drills, or excavates within two metres of suspected underground services needs competent CAT and Genny training. In practice, this covers a wide range of trades.

Groundworkers, civil engineers, utility maintenance operatives, streetworks teams, surveyors, electricians, plumbers, and highways crews all use CAT and Genny equipment regularly. Supervisors and site managers responsible for excavation planning also benefit from the course, even if they do not operate the equipment themselves.

Under the Health and Safety Executive guidance HSG47 Avoiding Danger from Underground Services, anyone using cable detection equipment on site must be trained and competent. The N304 course is the standard route to meeting this duty.

What does the N304 course cover?

The course is built around HSG47 and PAS 128, the two key reference documents for underground service detection in the UK.

The theory element covers legal responsibilities under the Health and Safety at Work Act 1974 and the Construction (Design and Management) Regulations 2015, interpretation of utility drawings and site service plans, the causes and consequences of service strikes, and the limitations of CAT and Genny equipment.

The practical element covers pre-use inspection and calibration of a CAT4+ and Genny4, correct scanning technique in Power, Radio, and Generator modes, tracing and marking buried services accurately, recognising signals from ferrous and non-ferrous utilities, and working safely in live site conditions.

How long is the NPORS N304 course?

The course runs over one full day, typically 8am to 4pm. This covers classroom theory, hands-on practical training, and the NPORS assessment. Class sizes are capped at six candidates to protect quality and give every learner adequate equipment time.

Delivery can be at a Target Zero training centre or on your own site if suitable equipment and open ground are available. On-site delivery is often preferred for teams of three to six operatives, because it removes travel time and uses the equipment the team works with day to day.

What qualifications do you need before booking?

There are no formal prerequisites for the theory and practical elements. However, anyone who wants the NPORS card to display the CSCS logo must also hold a current CITB Health, Safety and Environment touch screen test pass dated within the last two years.

The CSCS-logo NPORS card is the version accepted on most major principal contractor sites. The traditional NPORS card without the CSCS logo is suitable for non-construction sectors such as pure utilities or rail, but is less widely recognised.

If you need to sit the CITB HS&E test, our guide to CSCS test revision and where to practise walks through the preparation, and our free CITB HS&E mock tests let you test yourself against real exam conditions.

How is the N304 assessment structured?

Assessment is carried out on the same day as the training. It has two parts.

The theory test is a short multiple-choice and open-ended paper covering legal responsibilities, equipment operation, and underground service awareness. Most candidates complete it in 30 minutes.

The practical assessment asks the candidate to carry out pre-use checks, locate a set of buried services using both the CAT and the Genny, mark the services correctly on the ground, and explain their findings to the assessor. Practical time varies by candidate but usually runs 20 to 30 minutes per person.

Successful candidates receive an NPORS Operator card. If the candidate already holds an NVQ relevant to their occupation, they receive the Competent Operator card at initial certification, which is valid for five years.

How long does an NPORS CAT and Genny card last?

An initial NPORS Operator card is valid for two years. To retain certification, operators complete an NVQ in their occupation and upgrade to the Competent Operator card, which is valid for five years and renewable on CPD evidence.

At renewal, operators take a one-day NPORS refresher course and retest on the equipment. The refresher keeps operators current on legislation updates, new equipment features, and safe digging practice.

Traditional NPORS card vs NPORS CSCS card

Every NPORS plant operator category issues in two formats. The traditional NPORS card is recognised across utilities, rail, and other industries but does not carry the CSCS logo. The NPORS CSCS card carries the silver CSCS logo and is accepted on construction sites alongside CSCS cards issued through the core scheme.

For most construction work in 2026, you need the NPORS CSCS version. That requires the CITB HS&E test pass within the last two years, plus the NPORS assessment. Our guide to NPORS vs CPCS explains the differences between the two main plant card schemes and helps you decide which is right for your role.

Why CAT and Genny training matters

The HSE publishes annual figures on service strikes. Cable strikes alone cause electric shock, burns, explosions, and in the most serious cases fatalities. Beyond the human cost, a single strike on a gas main or high voltage cable can shut down a site for weeks, trigger prosecution under the Health and Safety at Work Act, and cost tens of thousands of pounds in repair and compensation.

Competent CAT and Genny use eliminates most of these risks. An operator who knows how to calibrate the equipment, interpret signal strength, and cross-check against site drawings will find buried services that a casual user would miss entirely.

How Target Zero can help

Target Zero delivers NPORS training across our core focus categories, including the N304 Cable Avoidance Tool qualification. We run courses at our training centres and on client sites across the UK, with assessors who have worked in civils and utilities themselves.

To book, visit our NPORS CAT & Genny Training (N304) page for course dates, pricing, and online booking. You can also browse the full range of NPORS courses or call our team on 01245 379496. We can arrange on-site delivery for teams of three to six, or offer open-course dates for individuals.

Frequently asked questions

Is CAT and Genny training legally required?

Anyone using cable avoidance equipment on site must be trained and competent under HSG47 and the Health and Safety at Work Act 1974. While the regulations do not specify a named qualification, NPORS N304 is the industry-recognised route to proving competence and is accepted by principal contractors nationwide.

How much does NPORS CAT and Genny training cost?

Prices vary by delivery format and location. On-site training for a full group of six is usually the most cost-effective option per candidate, while individual places on open courses are also available. Call Target Zero on 01245 379496 for a quote for your circumstances.

Can I do the N304 course if I have never used a CAT before?

Yes. The course is suitable for complete beginners. The one-day structure starts with equipment basics and builds up to full practical competence. No previous experience or qualification is needed for entry.

Do I need the CITB HS&E test before the N304 course?

Only if you want the NPORS card to display the CSCS logo, which is required for most construction sites. You need a current CITB HS&E test pass within the last two years. For non-construction work, the traditional NPORS card does not require the HS&E test.

What is the difference between CAT and Genny equipment?

A Cable Avoidance Tool (CAT) is a receiver that detects signals given off by buried services. A Signal Generator (Genny) is a transmitter that injects a traceable signal into a known service, such as a water pipe or telecoms cable, so the CAT can follow it. Used together, they give a far more reliable detection than either tool alone.

What happens if I fail the N304 assessment?

Candidates who do not meet the standard on the day can re-test once their trainer has identified the specific areas to address. Most learners pass on the first attempt because the one-day format reinforces both theory and practical skills immediately before assessment.

How often do I need to renew my NPORS CAT and Genny card?

The initial NPORS Operator card is valid for two years. Operators with a relevant NVQ receive the five-year Competent Operator card. All NPORS cards renew through a one-day refresher course that retests theory and practical competence.