Massachusetts Wastewater Practice Exam

When sampling, all representative samples must be preserved with __________ while being transported to the laboratory for analysis.

1. A. Sodium Hydroxide

2. B. Acid

3. C. Ice

4. D. Soft packing

The correct answer is: C. Ice

When transporting samples to a laboratory for analysis, it is critical to preserve the integrity of the samples to ensure accurate results. Using ice is a common and effective method of preservation because it acts to slow down any biological activity and chemical reactions that may alter the composition of the sample. Keeping samples cool during transportation helps to maintain their original state, especially for biological and chemical parameters that may be sensitive to temperature fluctuations. In many wastewater analyses, maintaining sample temperature below certain thresholds is essential for preventing degradation of organic matter and controlling microbial activity that could skew results. Therefore, using ice is a standard practice among professionals in the field to preserve the quality and reliability of wastewater samples until they can be analyzed in the lab.