American Society of Radiologic Technologist (ASRT) Practice Exam

What can be done to reduce the exposure dose to a patient during radiography?

1. Increasing the mAs

2. Decreasing the time

3. Increasing the focal spot size

4. Reducing the object-to-image distance

The correct answer is: Decreasing the time

Reducing the exposure dose to a patient during radiography can be effectively achieved by decreasing the time the patient is exposed to the radiation beam. This is important because exposure time is directly related to the total dose of radiation the patient receives. By reducing the time, you lessen the amount of radiation delivered, which minimizes the risk of potential adverse effects. In radiation safety, it is critical to keep the dose as low as reasonably achievable, known as the ALARA principle. Shortening the duration of exposure helps achieve this balance by providing the necessary diagnostic information with minimal risk. It is essential to optimize other factors such as equipment settings to ensure sufficient image quality while successfully reducing exposure time. Other options, while relevant in specific contexts, do not serve to reduce the patient’s exposure effectively. For example, increasing the mAs (milliamperes per second) actually increases the amount of radiation produced, which would increase the dose to the patient. Increasing the focal spot size can also lead to reduced detail and is not a standard method to reduce dose. Reducing the object-to-image distance would typically increase the radiation dose reaching the patient because of the inverse square law, which states that the intensity of radiation is inversely proportional to the square of the distance from the