What precaution must be taken when transporting air samples to a laboratory?

When transporting air samples to a laboratory, it is crucial that the samples are securely sealed to prevent contamination or loss. This precaution ensures the integrity of the sample is maintained from the point of collection to analysis. If samples are not properly sealed, they can become contaminated by external factors, such as dust, moisture, or other airborne particles, which could lead to inaccurate results. Secure sealing also minimizes the risk of sample loss due to accidental spillage or exposure to environmental conditions that may alter the sample composition.

In contrast, while exposure to sunlight could degrade certain types of samples, labeling the samples with the date and time of collection only fails to provide complete contextual information needed for accurate analysis. Additionally, maintaining the samples at room temperature may not be universally applicable, as temperature can vary based on the type of sample being analyzed and must be managed according to specific protocols and requirements for preserving integrity. Thus, securing the samples is the most fundamental step in ensuring reliable analytical outcomes.