Which item is NOT permitted on a school bus according to hazardous materials regulations?

Personal hazardous tools are not permitted on a school bus due to the safety protocols established in hazardous materials regulations. These regulations aim to protect the safety of all passengers and ensure a secure environment. Personal hazardous tools can pose risks such as injury or a violation of safety standards, which is why their presence on school buses is prohibited.

In contrast, medically prescribed oxygen may be necessary for some passengers' health needs and can be safely transported under specific conditions. Firearms carried by police officers are allowed due to the officer's legal authority and professional responsibility to ensure safety. Personal items by passengers, as long as they do not fall into hazardous categories, are generally allowed to accommodate students' everyday needs. Thus, the restriction against personal hazardous tools emphasizes the importance of maintaining a safe and secure environment for students while traveling on a school bus.