Somebody has told you that you need a weld radiographed, and somebody else has told you that means IRR17. If you have never run radiography on your site before, that acronym arrives with very little explanation attached and a strong implication that getting it wrong is expensive.
This is what the Ionising Radiations Regulations 2017 actually ask of you, in the order you will meet it, written for the person responsible for the site rather than for the radiographer.
First, who is responsible for what
IRR17 places its duties on the employer carrying out work with ionising radiation. For site radiography that is normally the inspection contractor — us — not you. That is the single most useful thing to understand early, because it means the bulk of the regulatory machinery is our problem: the HSE consent, the dosimetry, the source accountancy, the appointed people.
What does not transfer is your duty as the person in control of the premises. You have to co-operate. You have to let the controlled area be established and respected. You have to make sure your own people, and any other contractor on site that day, are not walking through a barrier because nobody told them what the flashing light meant. Where two employers share a workplace, the regulations expect them to co-operate so far as is necessary — and in practice that co-operation is where most of the friction lives.
Consent, not just notification
IRR17 grades regulatory oversight in three tiers: notification, registration, and consent. Industrial radiography sits in the top tier. An employer cannot carry out industrial radiography without HSE consent for that practice — it is not a form you send after the fact.
You do not apply for this. Your contractor holds it, and you are entitled to ask to see it. If a company offers to shoot a weld for you and cannot evidence consent for industrial radiography, that is the end of the conversation.
The prior risk assessment
Before any new activity involving ionising radiation begins, a suitable and sufficient risk assessment must be carried out. Not a generic one held on file — one that addresses this work, at this location.
A real radiography risk assessment answers questions that only get answered by knowing the site: what the source is and its activity, what is being exposed and for how long, what the dose rates will be at the boundary, where the boundary can physically go, what is on the other side of every wall and floor and ceiling within range, who else is working nearby, what happens if the source fails to retract, and how anyone would be got out.
That last one matters more than it sounds. The assessment has to consider reasonably foreseeable accidents and their consequences, and where a radiation accident is credible, a contingency plan has to exist and the people involved have to have rehearsed it. For gamma radiography the credible accident is a source that will not wind back into its shielded position, and the plan for it is not improvised on the day.
Restricting exposure, in that order
The regulations set a hierarchy and expect it to be followed in sequence. Engineering controls and shielding first. Then systems of work — distance, time, barriers, procedures. Personal protective equipment last, and only where the first two cannot do the job.
This is why a competent contractor will push you towards a shielded enclosure over an open-site shoot when the geometry allows it, and why they will ask about night work. It is not preference. Doing the exposure inside a purpose-built compound, or when the surrounding area is empty, is a higher-order control than putting a barrier round it and hoping.
It is also why source selection is a safety decision, not just a technical one. Selenium-75 and iridium-192 produce different dose rates and demand different boundary distances for the same job. Choosing the lower-energy source that will still make the exposure often shrinks the controlled area enough to make the difference between shutting an area down and not.
Controlled and supervised areas
An area has to be designated as controlled where special procedures are needed to restrict significant exposure, or where anyone in it is likely to receive more than 6 mSv a year. On a site shoot, the controlled area is the barriered zone around the exposure, and it exists once the barriers, signage and hand over are all in place.
In practice the boundary is set by survey, not by assumption. The radiographer calculates a predicted boundary, sets the barriers accordingly, and then measures — with a calibrated and tested monitor — to confirm the dose rate at the boundary is what it should be before the first full exposure. If the survey disagrees with the calculation, work pauses and the barriers move.
You will see the physical signature of this: barrier tape or rope, warning signs, flashing lights, and an audible warning. Those are not decoration. They are the mechanism by which the boundary means something to a person who has not read the risk assessment.
A supervised area is the lesser designation — somewhere conditions need keeping under review but full controlled-area procedures are not warranted. On most site radiography jobs the practical arrangement is a controlled area with barriers.
The appointed people
Two roles come up constantly and get confused constantly.
A Radiation Protection Adviser is a specialist the employer must consult, holding a current certificate of competence from a recognised assessing body. The RPA advises: on the risk assessment, on the designation of areas, on the adequacy of the plans, on dose investigation. They are usually not on site. Their job is judgement, and you consult them before problems, not after.
A Radiation Protection Supervisor is appointed by the employer to secure compliance with the local rules for the work actually being done. The RPS is on site. They are the person making sure the barriers stay up, the survey gets done, the dosimeters get worn, and the local rules get followed by the people they are written for.
Local rules themselves are a written requirement wherever a controlled area exists. They cover the key working instructions, the identity of the RPS, contingency arrangements, and the dose investigation level. Everyone working in or near the area should have had them explained.
Dose limits and dosimetry
The dose limits that matter for planning are the annual effective dose limits: 20 mSv for classified employees, and 1 mSv for members of the public and for non-classified persons. Your staff and other contractors on site are, for this purpose, members of the public. That 1 mSv figure is the number the controlled area boundary is designed to protect.
Radiographers likely to receive more than 6 mSv a year must be designated classified persons, which brings personal dosimetry through an HSE-approved dosimetry service and ongoing medical surveillance. Again — the contractor's obligation, but worth knowing exists, because it is the difference between a company that runs a controlled radiography operation and one that does not.
Sealed sources and accountancy
Gamma sources are sealed sources, and they carry their own regime: leak testing at defined intervals, records of receipt, movement, use and disposal, and secure storage. A source has to be accounted for at all times, and a missing source is an immediate reportable event.
What this means for you is straightforward. If radiography is happening on your site, the source arrives and leaves under a documented chain. Ask to see the source certificate and the leak test record. It takes thirty seconds and it tells you a great deal about how the rest of the job is being run.
What good preparation looks like from your side
You will make the job faster, cheaper and safer if you can answer these before the crew mobilises:
What exactly is being radiographed, where is it, and can it be moved to a shielded facility instead?
What is on the other side of every adjacent wall, floor and ceiling — including outside the building?
Who else is working in the area, and can that be scheduled away from the exposure window?
Is out-of-hours access possible, and who holds the keys?
Who is your point of contact when the controlled area needs to be enforced against one of your own people?
That last question is the one most often unanswered, and it is the one that costs the most time on the day.
The short version
IRR17 is not a document you need to have read. It is a set of controls that a competent contractor arrives already carrying: consent, a real risk assessment, an RPA behind it, an RPS in front of it, a surveyed boundary, dosimetry, and a rehearsed plan for the source that will not come back. Your job is to give them the information to do it properly and the authority to hold the boundary.
If you want to talk through a specific job — what it would take, whether it can be done in our compounds instead of on your site, and what the controlled area would look like — our RPA team will walk through it with you before anything is booked. If you already know what you need, the radiation work request form starts the IRR17 notification.
