Ionising radiation is frequently used in veterinary practice, primarily for diagnostic imaging. Radiation safety is an essential requirement for any practice using ionising radiation, and radiation safety breaches represent a significant health and safety incident and risk to the health of veterinary team members and their patients. Despite this, breaches are not uncommon in clinical practice. This article explores regulations and safety guidelines, challenges to implementation, and proposes solutions to improve radiation safety in companion animal practice. 

Risks and Regulation 

 Ionising radiation damages living tissue. However, the potential damage from an absorbed dose depends on the type and dose of radiation received and the sensitivity of the tissue or organ. High doses, exceeding those from diagnostic imaging radiation, can produce effects such as skin redness, hair loss, radiation burns, or acute radiation syndrome. These effects are more severe at higher doses and higher dose rates. 

If the radiation dose is low and/or it is delivered over a longer period, the risk is substantially lower. However, there is still a risk of effects such as cataracts or cancer that may appear years or even decades later. Studies in humans estimate increased occurrence of cancer in patients screened with CT, and perinatal irradiation was shown to increase neoplasia incidence in young dogs. Studies have found job related exposure to ionising radiation in veterinary practice to be associated with increased risk of spontaneous abortion in female veterinarians and veterinary assistants. However, the risks of X-ray radiation to both patients and people may be challenging to convey to personnel due to its invisible nature and the lack of acute symptoms following exposure. 

The Regulatory Landscape: A Global Overview  

Ionising radiation regulations for veterinary practices vary between countries and may even differ across regions within a country, e.g. different states in the USA and territories in Australia. However, most include the following principles:  

1. Risk Assessments: Practices are required to identify and mitigate risks associated with radiation exposure.  

2. Equipment Standards: Guidelines to ensure imaging equipment and surrounding shielding meet safety and performance criteria.  

3. Training Requirements: Personnel operating or exposed to radiation must be adequately trained in safety protocols, typically with named radiation safety officers required at each site where ionising radiation is used.  

4. Dose Monitoring: Systems to track radiation exposures and doses received for personnel, including staff and clients (e.g. horse owners restraining a patient for X-rays in the field).  

5. Personal Protective Equipment (PPE): Requirements for the availability and use of shielding such as lead aprons, gloves and thyroid collars. 

Recommendations 

To reduce radiation exposure risk in veterinary practice it is important to consider the important principle of keeping radiation use and dosage to both personnel and patients As Low as Reasonably Achievable (ALARA). In practice, this may include: