What should users do before entering an IDLH environment?

Before entering an Immediately Dangerous to Life and Health (IDLH) environment, inspecting personal protective equipment is crucial for ensuring the safety of the user. SCBA is designed to provide breathable air and protect the user from hazardous environments. By inspecting this equipment, users can identify any potential malfunctions, ensuring it is functioning properly and is adequate for the intended environment. Proper functioning of the SCBA is vital, as it is the primary means of protection against toxic atmospheres. Ensuring that the equipment is intact, free of damage, and has a full air supply can significantly impact the user's safety and effectiveness in potentially life-threatening situations.

The other options, while important in different contexts, do not directly relate to ensuring the SCBA will maintain safety during entry into an IDLH environment.