OMNERA® 1000-095-071-EN Rev. 1.1
Operator´s Manual
Page 24 2020-09-14
2.10.1 Radiation protection
Because of the ionizing nature of x-ray radiation, precautions have to be taken to minimize
the harmful effects to patients and operators/staff during exposures. The aim is to achieve
dose levels “as low as reasonable achievable”. National regulatory dose limitation require-
ments have to be followed.
Following four main factors control the amount (dose) of radiation received from a source:
Patient and operator dose:
Loading factors: Reducing the loading factors reduces the effective dose proportionally.
Lower values will give more noise in the image.
Distance: Increasing the distance reduces dose levels according to the inverse square law.
Beam size: Keep the beam size as small as possible.
Shielding: Whenever possible/necessary protective shielding should be used to limit dose
levels.
2.10.1.1 Protection against primary radiation (patient)
Following measures should to be taken to limit patient dose.
• Observe national dose limit regulations.
• Exposure parameters (time/mA) should be set as low as possible with an acceptable im-
age noise level.
• Set focus to skin distance as large as possible.
• Always collimate the exposure field to the area of interest. This will both decrease the dose
level and improve the image quality (less scattered radiation).
• If possible/necessary use protective shielding.
2.10.1.2 Protection against secondary radiation
As the patient is the most significant source of scattered radiation during an x-ray exam, the
staff and/or operator will unavoidable be exposed to ionizing radiation when inside the x-ray
room during an exposure. Radiation doses from scattered radiation can be significantly high.
Following safety measures should be taken to minimize scattered radiation to the staff.
• Increasing the distance to the central beam reduces dose levels according to the inverse
square law.
• Protective clothing, e.g. lead apron, should always be used.
• Exposure parameters (time/mA) should be set as low as possible.
• Using high kV and low mA produces less scatter.
• Always collimate the exposure field to the area of interest.
• Added collimator filter reduces the scatter.
• Compression of patient.
Safety
Radiation and X-ray tube
To Next Page
