If the operator stands behind a portable shield, what is the approximate total radiation dose reduction?

When an operator stands behind a portable shield while performing radiography, the shield plays a significant role in attenuating the radiation exposure. A well-designed portable shield can reduce the radiation dose received by the operator to a remarkable degree.

The correct choice reflects that standing behind a portable shield can result in approximately a 99% reduction in radiation dose. This substantial decrease is primarily due to the effectiveness of the material used in the shield, which is typically dense and designed specifically to absorb or deflect radiation, thereby protecting the operator from exposure.

Understanding this concept is crucial in radiography, as it emphasizes the importance of utilizing appropriate shielding techniques to ensure safety. The dramatic reduction in radiation exposure achieved by using portable shields underscores their value in protecting the operator's health while conducting radiographic examinations. This reduction not only enhances safety but also aligns with best practices in radiation safety protocols that advocate for minimizing exposure to the lowest possible levels through effective shielding methods.