Patient dose information: guidance
Published 4 September 2008
© Crown copyright 2008
This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@nationalarchives.gov.uk.
Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned.
This publication is available at https://www.gov.uk/government/publications/medical-radiation-patient-doses/patient-dose-information-guidance
This table gives typical effective doses, equivalent periods of natural background radiation and lifetime fatal cancer risks from diagnostic medical exposures.
1. X-ray examinations
| Diagnostic procedure | Typical effective doses (mSv) | Equivalent period of natural background radiation 1 | Lifetime additional risk of fatal cancer per examination 2 |
|---|---|---|---|
| Limbs and joints (except hip) | < 0.01 | < 1.5 days | 1 in a few million |
| Teeth (single bitewing) | < 0.01 | < 1.5 days | 1 in a few million |
| Teeth (panoramic) | 0.01 | 1.5 days | 1 in 2 million |
| Chest (single PA film) | 0.02 | 3 days | 1 in a million |
| Skull | 0.07 | 11 days | 1 in 300,000 |
| Cervical spine (neck) | 0.08 | 2 weeks | 1 in 200,000 |
| Hip | 0.3 | 7 weeks | 1 in 67,000 |
| Thoracic spine | 0.7 | 4 months | 1 in 30,000 |
| Pelvis | 0.7 | 4 months | 1 in 30,000 |
| Abdomen | 0.7 | 4 months | 1 in 30,000 |
| Lumbar spine | 1.3 | 7 months | 1 in 15,000 |
| Barium swallow | 1.5 | 8 months | 1 in 13,000 |
| IVU (kidneys and bladder) | 2.5 | 14 months | 1 in 8000 |
| Barium meal | 3 | 16 months | 1 in 6700 |
| Barium follow | 3 | 16 months | 1 in 6700 |
| Barium enema | 7 | 3.2 years | 1 in 3000 |
| CT head | 2 | 1 year | 1 in 10,000 |
| CT chest | 8 | 3.6 years | 1 in 2500 |
| CT abdomen/pelvis | 10 | 4.5 years | 1 in 2000 |
2. Nuclear medicine studies
| Diagnostic procedure | Typical effective doses (mSv) | Equivalent period of natural background radiation 1 | Lifetime additional risk of fatal cancer per examination 2 |
|---|---|---|---|
| Lung ventilation (Kr-81m) | 0.1 | 2.4 weeks | 1 in 200,000 |
| Lung perfusion (Tc-99m) | 1 | 6 months | 1 in 20,000 |
| Kidney scan (Tc-99m) | 1 | 6 months | 1 in 20,000 |
| Thyroid scan (Tc-99m) | 1 | 6 months | 1 in 20,000 |
| Bone scan (Tc-99m) | 4 | 2 years | 1 in 5000 |
| Dynamic cardiac (Tc-99m) | 6 | 2.7 years | 1 in 3300 |
| Myocardial perfusion (Tl-201) | 18 | 8 years | 1 in 1100 |
1UK average = 2.2mSv per year: regional averages range from 1.5 - 7.5 mSv per year
2 Approximate lifetime risk for patients 16 to 69 years old: for paediatric patients multiply risks by about 2 for geriatric patients divide risks by about 5