Explain the term 'radiation hazard.'

The term 'radiation hazard' refers to a situation where exposure to radiation can lead to harm or injury to health. This encompasses the potential risk associated with various types of radiation, including ionizing radiation, which can damage living tissue and DNA, leading to serious health issues such as cancer or acute radiation syndrome. Understanding radiation hazards is crucial in ensuring safety protocols are followed to limit exposure to harmful radiation levels in various environments, such as medical facilities, nuclear power plants, or even during radiological emergencies.

The other choices do not appropriately define 'radiation hazard.' Ignoring a substance with hazardous radiation risks can lead to severe health consequences, so this option is misleading. While radiation shielding is important for protection, it's more a method used to mitigate hazards rather than defining them. Lastly, a device that measures radiation levels helps assess hazards but does not encapsulate the concept of a radiation hazard itself. Therefore, recognizing the implications and contexts of exposure makes the correct answer focused on health risks associated with radiation exposure.