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Radiation Protection Regulations in the UK. Craig Moore Radiation Protection Adviser Radiation Physics Department CHH Oncology. But first…. What we do in Radiation Protection We are part of Radiation Physics Service (other half is Radiotherapy Physics) Based in Oncology CHH
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Radiation Protection Regulations in the UK Craig Moore Radiation Protection Adviser Radiation Physics Department CHH Oncology
But first….. • What we do in Radiation Protection • We are part of Radiation Physics Service (other half is Radiotherapy Physics) • Based in Oncology CHH • We provide scientific and technical support in the fields of • Ionising (x-rays, etc.) and non-ionising (lasers, UV, MRI, etc.) radiation safety • Diagnostic imaging physics (including equipment quality assurance) • Radiotherapy metrology, treatment planning, equipment management • Research & development • Teaching & training
Who are we?? • Radiation Protection Advisers • John Saunderson – x76-1329 • Craig Moore – x76-1385 • Rad’n Prot’n Team • Andrew Davis, Dave Strain, Tim Wood – ext. 76-1330 • Radiation Protection website • www.hullrad.org.uk • Trust Policy CP137
What’s the Point in Legislating? • Ionising radiation such as X-rays can cause the following effects: • Tissue effects such as skin burns and loss of hair • Stochastic effects (per 1 mSv) • 1 in 20,000 risk of fatal cancer • 1 in 100,000 risk of non fatal cancer • 1 in 77,000 risk of hereditary effects • Staff receive radiation doses from X-rays that scatter from the patient and radiation emanating from patient • Ionising radiation is invisible so you can’t see or smell it, hence it can cause damage without you knowing about it (at first!!!)
The Ionising Radiations Regulations 1999 (IRR99) • Protection of • Staff • Public from ionising radiation
Authorisation • Enforced by the Health and Safety Executive
Structure of IRR99 • 7 ‘Parts’ • 41 Regulations • 9 Schedules • Approved Code of Practice - Statutory Guidance (HSE approved) • Non-statutory guidance (i.e. guidance notes)
Statutory and Non-Statutory Guidance • Approved code of Practice & HSE Guidance • Medical & Dental Guidance Notes
So what’s included in IRR99 • General Principles and Procedures • Risk assessment • Dose restriction • Dose limitation • Arrangements for the Management of Radiation Protection • Radiation Protection Adviser • Radiation Protection Supervisor • Local Rules • Designated Areas • Controlled Areas • Classification and Monitoring of Persons • Dose badges • Control of Radioactive Substances • Duties of Employees • All of us have duties under these regulations
Reg 7: Prior Risk Assessment • Must be undertaken before work commences with ionising radiations • Identify hazards • Decide who might be harmed and how • Evaluate risks and decide whether existing precautions are adequate or not • Record findings of risk assessment • Review and revise it • By Law has to be done (or approved) by a certified Radiation Protection Adviser
Reg 8: Restriction of Exposure • Doses must be optimised • As Low As Reasonably Practicable (ALARP) • Hierarchy of protection measures: • Engineering controls such as the design of X-ray tubes and shielding • Systems of work such as local rules • PPE such as lead aprons • Dose constraints (planning) • 1 mSv to foetus during declared term • Formal Investigation levels of staff dose
Regs 9: Personal Protective Equipment • Should be provided where necessary • Should comply with PPE regulations • Should be properly maintained
Lead Apron Storage • Always return to hanger • Do not • fold • dump on floor and run trolleys over the top of them!!! • X-ray will check annually • But if visibly damaged, ask X-ray to check them.
Reg 10: Engineering Controls • All safety features of an installation must be maintained and tested at suitable intervals • QA manual should spell out who does what (user, engineer, physics etc)
RADIATION TISSUE Radiation Dose • Absorbed Dose (Jkg-1) • Amount of energy deposited per kilogram • Dose to an organ or tissue • Unit is the Gray (Gy) • DOSE TO A CERTAIN PLACE IN THE BODY • Effective Dose (Jkg-1) • This is the average dose to whole body • Unit is the Sievert (Sv) • This gives us the risk of contracting cancer of the x ray exposure • THIS IS THE OVERALL DOSE TO THE WHOLE BODY
External and Internal dose • Dose from external sources • X-ray • Radiation emanating from patient (Nuclear Medicine and Brachytherapy) • Contamination of work surfaces etc • Dose from internal sources: • Ingestion • Inhalation • Absorption • Committed effective dose • Dose delivered due to deposition of radionuclide in the body
Reg 11: Dose Limits for staff & public (mSv) per calendar year Possibly changing to 6 mSv/yr in a couple of years
Dose Monitoring • Most employees who work with radiation in a Hospital Trust have radiation monitoring badges. • These monitor the exposure to radiation of an employee • Doses received are assessed by the RPA to ensure they are being kept ALARP • BUT, it is also an RPS duty to monitor results • Please ensure your staff wear and return it promptly • There have been recent prosecutions for not doing so under these regulations
Typical Dose Monitoring Results across the Trust • Physics: • Typically less than 0.1 mSv/month • This equates to less than 1 mSv/yr • Much lower than legal limit of 6 mSv/yr • Radiotherapy: • Typically less than 0.1 mSv/month • This equates to less than 1 mSv/yr • Much lower than legal limit of 6 mSv/yr • Nuclear Medicine: • Typically less than 0.3 mSv/month • This equates to less than 4 mSv/yr • Lower than legal limit of 6 mSv/yr • Radiology: • Typically less than 0.3 mSv/month • This equates to less than 4 mSv/yr • Lower than legal limit of 6 mSv/yr • Dental: • Typically less than 0.1 mSv/month • This equates to less than 1 mSv/yr • Much lower than legal limit of 6 mSv/yr • Under reg 8 we have to set dose investigation levels
Dose Investigation Levels • Physics: • 0.1 mSv/month • Radiotherapy: • 0.1 mSv/month • Nuclear Medicine: • 0.5 mSv/month • Radiology: • 0.35 mSv/month • Dental: • 0.1 mSv/month • Breast Screening: • 0.1 mSv/month
Women of reproductive capacity • Refers to ‘women at work’ • But 1 mSv to foetus during declared term
Exclusions to Dose Limits • Comforter and Carer • These knowingly and willingly incur an exposure having been fully advised of the risks • Not as part of their job • What about the other? • Persons undergoing medical exposure
Reg 12: Contingency plans • Contingency plan required for ‘reasonably foreseeable’ accident • Radiotherapy: • Emergency stop buttons • In Brachytherapy if the source fails to retract during treatment: • Take out applicators and place in lead pot • Wire cutters may be needed in some instances! • Radiology: • Emergency stop buttons • Nuclear Medicine: • Spills and contamination • Plan must be documented in Local Rules • Must be rehearsed at appropriate intervals dependent on: • Potential severity • Likely doses • Complexity of plan • Number of people involved • Involvement of emergency services
Part 3 Arrangements for the Management of Radiation Protection
Reg 13: Radiation Protection Adviser • RPA must be suitably qualified • Must be certified by HSE approved body • Employer must consult RPA on the following matters: • Implementation of Controlled and Supervised Areas (eg signage) • Prior examination of plans for installations and the acceptance into service of new or modified sources of radiation in relation to safety and warning features • Regular calibration of equipment provided for monitoring levels of ionising radiation • Regular checking of systems of work provided to restrict exposure to ionising radiation • In addition, employer should consult RPA on: • Risk assessment • Designation of controlled areas • Conduct of investigations • Drawing up of contingency plans • QA programmes • In this Trust: • Craig Moore • John Saunderson
Reg 14: Information, Instruction and Training • Employees must receive adequate training • Risks from ionising radiations • Precautions to reduce risk • Importance of complying with regs • Also need training under the IRMER regulations (much more physics!!!!!)
Reg 15: Cooperation between employers • If staff work in controlled areas of other employers (private hospitals for example) • Must be able to demonstrate that total dose is less than 6 mSv/yr • Improvement notice has been issued at another Trust recently • Also needs to be clear which procedures staff members have to follow • HEY Trust or other employer
Part 5 Designated Areas
Reg 16: Designation of Controlled and Supervised Areas • Based on risk assessment • Controlled • ……..if it is necessary to follow special procedures to restrict significant exposure to ionising radiation in that area or prevent or limit the probability and magnitude of radiation accidents of their effects, • or any person working in that area likely to receive effective dose greater than 6 mSv or 3/10 of any other dose limit (eye, hands etc)
Reg 16: Controlled Areas • External Beam Radiotherapy: • LINAC treatment room including the maze when the unit is switched on • Brachytherapy: • Whole of treatment room whilst the treatment unit is capable of sending source out • Radiology & BSU: • Whole room when the unit is switched on • Nuclear Medicine: • Radiopharmacy • Dispensing room • Waste Store • Therapy Room • Dental: • 1.5m or 2 m from the patient (depending on workload)
Reg 17: Local Rules & Radiation Protection Supervisors • Local rules must be provided for controlled areas • RPS’s must be appointed if an area is subject to local rules
Local Rules • Local Rules must be written and adhered to for every radiation controlled area • Essential contents of local rules include: • Dose investigation level • Contingency arrangements • Name of radiation protection supervisor & Adviser • Identification of area covered • Working instructions • Local rules may also contain management and supervision of the work • Testing of engineering controls • Radiation monitoring • Testing of monitoring equipment • Personal dosimetry • Arrangement for pregnant and breastfeeding staff
Reg 17: Radiation Protection Supervisor • There to ensure local rules are being followed • Knowledge of regulations and Local Rules • Ability to command respect • Understanding of precautions required and extent to which these will restrict exposures RPS must be adequately trained
Reg 18: Additional requirements for designated areas • Physical demarcation of controlled areas • Warning signs (controlled and supervised) • Entry restricted to controlled areas
Reg 19: Monitoring of Designated Areas • Legal requirement to monitor dose rates around controlled area at commissioning • Monitoring at appropriate frequencies • Monitoring recorded and reviewed • Results kept for two years by qualified person • Monitoring equipment maintained and tested at regular intervals • Also carry out monitoring with badges stuck on walls every couple of years
Reg 21: Dose assessment and recording • In this Trust, anyone working in a radiation controlled area must wear a dose badge • Unless the dose to this employee can be shown to be low by other means
Regs 27 to 30 • About control of radioactive substances • Reg 27: • Sources should be sealed if possible • Containers must be fit for purpose • Suitable leak tests must be carried out • Reg 28: • Accounting for sources • Must know where all sources are at any time • Reg 29: • Keeping and moving of sources • Suitable stores • Suitable receptacle for moving • Reg 30: • Have to notify HSE if radioactive substance is no longer under his control
Reg 31:Duties of Manufacturers • Design & construct X-ray units and other articles to restrict exposure & ALARP • Perform critical examination upon installation • Safety features • Consult RPA on crit ex • Provide proper instructions on proper use, testing and maintenance
Reg 32: Quality Assurance Programme • A suitable quality assurance programme to be provided ensuring that equipment remains capable of restricting exposure to radiation • Adequate testing before clinical use • Adequate testing of the performance throughout lifetime of equipment • Assessment of representative doses • Handover procedure(s) • As an engineer you must ensure that after you have tested the equipment, it is handed back in a clinically fit state
All X Ray Equipment • Should have a lights on the control panel to show mains switched on • Fitted with a light/indications that gives a clear indication that an exposure is taking place • Exposure switches/peddles should only function while continuous pressure is applied
Reg 34: Duties of Employees • Must not recklessly interfere with sources • Must not expose themselves unnecessarily • Report immediately to the RPS/Employer if an incident or accident has occurred
Duties of Employees – DO NOTS • DO NOT X-ray yourself (even if you think you have broken a bone) • DO NOT X-ray your colleagues (even if you suspect they have broken a bone) • DO NOT fail to use lead glass screen properly • DO NOT fail to wear lead aprons and thyroid collars (if you have a thyroid collar!!) • DO NOT fail to wear any other PPE correctly • DO NOT fail to report to your RPS any defects in lead aprons • DO NOT fail to return lead aprons to their hangers • DO NOT tamper with dose badges • DO NOT hand badges in late • DO NOT fail to wear badges UNDER your lead apron • DO NOT fail to inform your RPS if you believe yourself or someone else has received an overexposure
Notification of Incidents • Must report to external body when the dose to a patient is ‘much greater than intended’ • If it was a machine fault this must be reported to the HSE • If any other fault (e.g. radiographer) then inform Care Quality Commission
Exposures much greater than intended • Diagnostic multiplying factors • HIGH DOSE PROCEDURES • Barium, angio, NM(>5 mSv), CT • 3 x • MEDIUM DOSE PROCEDURES • Lumber spine, abdo, pelvis, mammo • 10 x • LOW DOSE PROCEDURES • Extremities, skull, dental, chest • 20 x • Radiotherapy (inc NM therapy) • Whole course x 1.1 • One fraction x 1.2 • Also: • Incorrect patient • Incorrect anatomy of the correct patient
Incidents • Any untoward occurrence that may have resulted in excess radiation to staff or patients must be referred to the RPS and RPA • The RPA will estimate the dose and inform management, HSE, CQC etc if necessary • Suspect equipment must be withdrawn from service and labelled accordingly.
Female Staff of Child Bearing Age • Staff working with radiation are naturally concerned to minimise the risk to a foetus should they become pregnant • IRR99 places the onus on the employer to provide adequate information and on the employee to inform that they are pregnant • The employer must: • ensure that the dose to the foetus does not exceed 1 mSv • Notify female employees working with radiation the risk to the foetus, and the importance of informing the employer in writing as soon as they are pregnant
Doses and Risk to the Foetus • Current legal limit to foetus is 1 mSv • For X-ray, this corresponds to around 2 mSv to the abdomen • Assuming 8 months of declared pregnancy, dose to abdomen must be kept below 0.25 mSv per month • For X-ray, over many years, experience tells us that these dose levels are never reached in most areas of Trust, assuming Local Rules are followed • Only areas that work may need to cease is when using radioactive sources • Dose to abdomen = dose to fetus (e.g. higher energies from Tc99m)
Conclusions – Staff Pregnancy • Staff should inform their RPS as soon as they learn that they are pregnant • RPA must then carry out a risk assessment (if required) • Usually, provided Local Rules are followed, there are no grounds for amending staff working practice during pregnancy