The designation RQ identifies the material's ___.

The designation RQ stands for "Reportable Quantity," which is a critical term in the context of hazardous materials. This designation indicates the minimum quantity of a hazardous substance that, if spilled or released, must be reported to the appropriate authorities. The RQ helps to ensure that safety measures and emergency response protocols are activated promptly to mitigate potential public health and environmental risks.

For instance, if a transport incident occurs and hazardous materials are involved, knowing the RQ allows responders to assess the situation and take necessary actions based on the quantity of the material released. It plays a vital role in regulatory compliance and maintaining safety standards, as different substances may have different RQs depending on their levels of toxicity, environmental hazard, and potential impact on human health.

The other options do not accurately reflect the meaning of RQ in this context. Registered quality, recovery quantity, and risky quantity do not pertain to the reporting requirements for hazardous materials and thus do not serve the same regulatory and safety function as Reportable Quantity does.