How confident are you that your dental unit waterlines (DUWLs) are safe? If you’re relying on water that looks clean or assuming that flushing is enough to keep bacteria at bay, you may be exposing your patients—and your practice—to serious risk.
Dental waterlines are a hidden battleground against microbial contamination. Biofilm—the slimy, bacterial buildup inside DUWL tubing—forms rapidly and can release harmful bacteria into patient treatment water. Infections linked to contaminated dental waterlines include Legionnaires’ disease, endocarditis, and mycobacterial infections, some of which have led to high-profile outbreaks in pediatric dental offices.1
Despite increasing regulatory guidance from the CDC, ADA, and EPA, many dental professionals unknowingly follow outdated or ineffective waterline maintenance protocols. Let’s separate fact from fiction and uncover what really works when it comes to keeping your dental water safe.
Myth #1: If My Water Looks and Smells Clean, It’s Safe
Reality: Just because your water looks clear doesn’t mean it’s free of harmful bacteria. Studies have shown that dental unit waterlines can harbor bacterial counts exceeding 200,000 CFU/mL, which is a shocking contrast to the CDC’s recommended limit of 500 CFU/mL.2 Even if the source water is clean, biofilm can quickly contaminate it once inside the waterlines. Bacteria doubles every 4–20 minutes in untreated water, meaning that within a few hours, a low bacterial load can spiral into a full-scale contamination problem.3
Solution: Routine testing is critical. The FASTCheck15™ in-office test provides results in just 15 minutes, so you can confirm water safety before your first patient of the day. Pairing it with the Sterisil® R2A Mail-in Test with FASTRead™ offers detailed CFU counts for long-term tracking and compliance documentation—plus an early notification feature within 24 hours* if your samples exceed the water safety limit.
Why Paddle, when you can FASTCheck15™?
Paddle tests can take days, and they’re often messy, unclear, and easily misread. FASTCheck15™ offers fast, reliable pass/fail results in just 15 minutes, helping you to stay on top of water safety with ease.
FASTCheck15™ is:
- Faster, easier, and more affordable than paddles
- Enables regular monitoring of water safety to the 500 CFU level
- Ensures patient safety and testing compliance
Together, FASTCheck15™ and R2A with FASTRead™ offer a superior combination of testing—It’s About Time!
Myth #2: Shocking the Waterlines Alone is Enough to Control Bacteria and Biofilm Growth
Reality: Shocking alone does not provide continuous antimicrobial treatment that constantly kills bacteria, which prevents biofilm growth from reaching dangerous levels. Biofilm is like plaque on teeth—it must be actively removed or controlled with antimicrobial treatment.4
Even after shocking, if biofilm is left behind, bacteria can repopulate within days. This is why some practices experience a yo-yo effect—failing waterline tests shortly after treating their systems. Solution: An effective Test, Shock, Maintain protocol ensures:
- Testing detects early contamination and confirms compliance.
- Shocking with Citrisil™ Shock Tablets kills free-floating bacteria and suppresses biofilm growth.
- Maintenance with Sterisil® Straws delivers continuous antimicrobial protection for 365 days, significantly reducing the risk of biofilm regrowth.
Myth #3: All Waterline Treatment Products Work the Same Way
Reality: Not all waterline treatments are equal. Some systems rely on:
- Chlorine (bleach) – Requires specific water-to-chlorine ratios depending on type, corrodes dental unit equipment, and use for dental waterlines is off-label. Failure to fully flush can be harmful to patients.
- Iodine – Requires frequent maintenance and monitoring with iodine test strips and iodine efficacy depletes a few months after installation.
Sterisil’s silver-ion technology offers:
✔️ Longer-lasting disinfection (365-day protection with Sterisil® Straws)
✔️ Non-corrosive properties (safe for handpieces and dental units)
✔️ Proven efficacy—20× more effective than iodine at reducing CFU counts5
Solution: Upgrade to a complete solution that integrates testing, shock treatment, and long-term maintenance to keep your waterline safety on autopilot.
Myth #4: Waterline Compliance is Just a Regulatory Hassle
Reality: Waterline compliance isn’t just about meeting state regulations and guidelines—it’s about protecting your patients and staff.
While some states, such as Washington (2021) and Georgia (2025) have implemented state dental waterline testing requirements, more than 30 states mandate adherence to CDC and EPA guidelines for dental waterline maintenance and monitoring.6 Following regulations not only reduces risk to your practice, it is ethically right to ensure the procedural water for your patients and the aerosols that affect your staff is safe.
Multiple outbreaks of nontuberculous Mycobacteria (NTM) infections have occurred in children who received pulpotomies in pediatric dental clinics where the dental treatment water contained high levels of bacteria. Complications from their infections included permanent tooth loss, hearing loss, facial nerve palsy, and incision fibrosis. These outbreaks of NTM in pediatric dental offices have resulted in:
- 2015 (Georgia) — 24 children infected from pulpotomy procedures.7
- 2016 (California) — 71 pediatric patients infected from pulpotomy procedures; one child died.8
- 2022 (Georgia) — CDC was notified of a new cluster of suspected infections in children following procedures at a pediatric dental clinic.8
Even in states without mandatory testing, the CDC, ADA, and Association for Dental Safety (ADS formerly OSAP) strongly recommend routine waterline testing and treatment to prevent contamination-related failures. Neglecting waterline maintenance can result in:
🚫 Unexpected test failures that disrupt patient care
🚫 Legal liabilities, fines, and practice closure when a patient develops an infection
🚫 Negative patient perception that damages trust and reputation
Solution: A simple, repeatable protocol using the Sterisil® SAFEWATER Solution helps you:
✅ Catch problems early with FASTCheck15™ in-office testing
✅ Clean waterlines and suppress biofilm using Citrisil™ Shock Tablets
✅ Effectively prevent biofilm regrowth with Sterisil® Straw for 365 days with zero daily maintenance
A Smarter Approach to Waterline Safety
Waterline safety isn’t just another box to check—it’s a critical part of patient protection and practice success. The Sterisil® SAFEWATER Solution provides:
✔ Silver-ion technology for continuous disinfection
✔ FASTCheck15™ and R2A testing for compliance confidence
✔ A streamlined, easy-to-follow protocol that works better together
With a proven protocol for testing, shocking, and maintaining your waterlines, you can ensure consistent compliance and safer water for every patient, every day.
Learn more at solmetex.com/SafeWater
REFERENCES
- Best Practices for Dental Unit Water Quality. CDC. 2024. https://www.cdc.gov/dental-infection-control/hcp/dental-ipc-faqs/best-practices-dental-unit-water-quality.html
- Barbeau J, Tanguay R, Faucher E, et al. Multiparametric analysis of waterline contamination in dental units. Appl Environ Microbiol. 1996;62(11):3954-3959. doi:10.1128/aem.62.11.3954-3959.1996
- Troubleshooting Dental Water Quality Problems. ADS. 2024. https://www.myads.org/topics-duwl–troubleshooting-dental-water-quality-problems
- Dental Unit Waterlines: Questions and Answers. ADS. 2024. https://www.myads.org/topics-duwl-questions-and-answers
- Walker, JT, Bradshaw, DJ, Fulford, MR. Comparative Efficacy of Waterline Treatment Solutions in Controlling Biofilm Formation. J Dent Res. 2019:98(12), 1234-1240.
- Summary of Infection Prevention Practices in Dental Settings. CDC. 2024. https://www.cdc.gov/dental-infection-control/hcp/summary/dental-unit-water-quality.html#:~:text=All%20dental%20units%20should%20use,mL%20of%20heterotrophic%20water%20bacteria)
- Georgia Pediatric Dental Mycobacterium abscessus Infections. CDC Outbreak Report. 2015. Retrieved from: https://www.cdc.gov/mmwr/volumes/65/wr/mm6513a5.htm
- Outbreaks of Nontuberculous Mycobacteria Infections Highlight Importance of Maintaining and Monitoring Dental Waterlines. CDC Outbreak Report. 2022. Retrieved from: https://archive.cdc.gov/#/details?url=https://www.cdc.gov/han/2022/han00478.html
*Early notification within 24 hours of receipt of sample. Not all test failures can be identified within 24 hours. Final test results are available in 5–7 days on the My Solutions Center portal.
