Canadian Council of Independent Laboratories (CCIL) Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

When a sample contains aggregate that exceeds the appropriate size for the moulds, wet-sieving is a necessary procedure before testing. Wet-sieving involves using a sieve with water to separate the larger particles from the finer materials. This process ensures that the aggregate conforms to the required specifications for testing and helps achieve more consistent results.

By wet-sieving, one can effectively manage the particle size distribution within the sample, ensuring compliance with testing standards. This technique is particularly important in laboratory settings, where precise measurements and reactivity of materials are critical for valid outcomes. If the aggregate is too large, tests conducted on the sample could yield inaccurate results or fail to represent the behaviour of the material in practical applications.

The other options would not adequately address the problem of oversized aggregates. Discarding the sample without any treatment does not allow for the possibility of recovery or proper testing. Crushing down the aggregate might introduce variability and affect the properties of the material, and using the sample as is would directly contradict the requirements for appropriate particle size, leading to unreliable test results. Therefore, wet-sieving is the correct and most effective approach in this scenario.