Level B PPE is used when:

Level B Personal Protective Equipment (PPE) is specifically designed for situations where the potential hazards in the environment require a higher level of respiratory protection than skin protection. This type of PPE includes a high level of respiratory protection, such as a self-contained breathing apparatus (SCBA), while also providing some degree of protection for the skin, but not as comprehensive as Level A PPE.

In scenarios where there are significant respiratory hazards, such as toxic gases or vapors, using Level B PPE ensures that individuals can operate in a contaminated atmosphere with adequate breathing protection. Skin protection is necessary, but the primary focus in this case is on ensuring the respiratory system is safeguarded due to the identified risks.

Other options suggest situations that do not align with the intended use of Level B PPE. For instance, claiming that no respiratory protection is required or that the environment is completely free of hazards does not justify the need for Level B, which inherently assumes some hazardous conditions are present. Skin protection alone being adequate would not warrant the use of Level B, as it is primarily aimed at scenarios where inhalation hazards exist, emphasizing the critical aspect of protecting the respiratory system.