Medical Device Reprocessing Association of Ontario (MDRAO) Practice Exam

When should high-level disinfectant (HLD) be tested for minimum concentration?

1. Once a week

2. Before each use and at the start of the day

3. After every cleaning cycle

4. Only when changing disinfectants

The correct answer is: Before each use and at the start of the day

Testing high-level disinfectant (HLD) for minimum concentration before each use and at the start of the day ensures that the disinfectant is effective in providing the intended level of disinfection. This approach is critical as the potency of disinfectants can degrade over time due to factors such as exposure to air, light, and temperature fluctuations. By testing at the start of each day or before each usage, healthcare facilities can guarantee that they are using HLDs that meet the minimum effective concentration required for safe and effective disinfection, thereby reducing the risk of infection transmission. Ensuring the concentration is optimal is especially important in settings such as healthcare facilities where surgical instruments and medical devices require thorough disinfection to prevent cross-contamination and safeguard patient safety. Regular monitoring provides confidence that disinfection protocols are being followed properly and that the efficacy of disinfection is maintained throughout its use. The alternatives of testing weekly or only when changing disinfectants do not provide adequate assurance about the effectiveness of the HLD used on a day-to-day basis or for each specific use. Testing after every cleaning cycle might not be practical in many environments and could lead to unnecessary waste of resources if the testing frequency is not tailored to the actual usage and risk factors involved.