If there are no manufacturer use recommendations, a pesticide applicator should replace the chemical cartridges of his or her respirator:

A pesticide applicator should replace the chemical cartridges of their respirator at the end of each workday when there are no manufacturer use recommendations available. This practice is crucial for maintaining respiratory protection, as cartridges can become saturated or lose their effectiveness over time, especially in environments with high levels of chemical exposure or during prolonged use.

Replacing the cartridges at the end of each workday ensures that the respirator remains effective for the next use, minimizing the risk of inhaling harmful vapors, gases, or particulates. The focus on daily replacement aids in maintaining a robust safety protocol. While other frequencies for replacement might seem reasonable in different contexts, daily replacement is a safe guideline in the absence of specific recommendations, as it prioritizes the user's health and safety above all.