Water Damage Restoration Technician (WRT) Certification Practice Test 2026 – Your All-in-One Guide to Mastering the Exam!

In the context of desiccant dehumidification for a Class 4 water loss, the determination of the correct CFM (cubic feet per minute) is based on the specific characteristics of the space and the nature of the water intrusion. Class 4 water losses involve materials with high porosity, such as hardwood floors, structural materials, and concrete, requiring a more aggressive approach to moisture removal.

For a structure with a 2,000 square feet area and 9-foot ceilings, the total volume is 18,000 cubic feet (2,000 sq ft x 9 ft). The general guideline for initial airflow when utilizing desiccant dehumidifiers is to aim for about 1 CFM per 100 square feet of the affected area, adjusted based on the type of materials and severity of moisture present.

In this case, aiming for an initial CFM of 900 is appropriate, as it corresponds to addressing the required airflow based on the square footage while considering the demanding conditions of a Class 4 loss. This figure provides adequate air movement necessary to effectively distribute the dehumidification process and assist in achieving optimal moisture removal in the specified environment.

Understanding the requirements of different classes of water damage ensures the correct application of