How many levels of PPE are mentioned in the context of emergency response?

The correct answer indicates that there are four distinct levels of Personal Protective Equipment (PPE) used in the context of emergency response, particularly in hazardous materials operations. Each level of PPE is designed to offer different degrees of protection based on the types of hazards present and the potential risks to responders.

These levels range from minimal protection to full encapsulation, allowing responders to select appropriate gear based on situational assessments. Level A provides the highest level of protection, often including a fully sealed suit with supplied air, suitable for environments with unknown or highly dangerous chemicals. Level B protects against vapors and requires a lesser degree of skin protection than Level A, frequently involving an air-supply system but less coverage. Level C uses chemical resistant clothing but relies on an air-purifying respirator, appropriate when the hazards are known and can be controlled. Lastly, Level D is the lowest level of protection, typically involving standard work uniforms for nuisance contamination where no harmful exposure is expected.

Understanding these levels is crucial for responders to adequately prepare for various hazardous scenarios and ensure safety while performing their duties.