Actual exposure time must be within what percentage of the indicated exposure time?

Actual exposure time must be within what percentage of the indicated exposure time?

• A. +/- 5%
• B. +/- 1%
• C. +/- 2%
• D. +/- 10%

Answer: (A)

Exposure time accuracy is checked to ensure the timer delivers what is shown on the control panel. The accepted tolerance is within 5% of the indicated time, so the actual exposure time should be within plus or minus 5% of the setting. This keeps patient dose predictable and images consistently exposed. For example, if the unit is set to 0.2 seconds, the actual time should be between 0.19 and 0.21 seconds. If the timing drifts beyond this range, you can get noticeable changes in brightness and dose, leading to under- or overexposure. While some systems or testing protocols may have tighter or different requirements, the standard practical tolerance for exposure time is ±5%.

Exposure time accuracy is checked to ensure the timer delivers what is shown on the control panel. The accepted tolerance is within 5% of the indicated time, so the actual exposure time should be within plus or minus 5% of the setting. This keeps patient dose predictable and images consistently exposed. For example, if the unit is set to 0.2 seconds, the actual time should be between 0.19 and 0.21 seconds. If the timing drifts beyond this range, you can get noticeable changes in brightness and dose, leading to under- or overexposure. While some systems or testing protocols may have tighter or different requirements, the standard practical tolerance for exposure time is ±5%.