EPA has enforced pretreatment standards to reduce discharges of mercury from dental offices into publicly owned treatment works (POTWs). The Dental Office Category
regulation is found in 40 CFR Part 441
. The final rule went into effect June 14, 2017.
Dental facilities that places or removes amalgam will be subject to this rule. This rule includes an amalgam separator requirement, best
management practices (BMPs) requirement, and a one-time submission of a Dental Dischargers Compliance Form
Dental practices exempt from this rule include:
- Oral pathology
- Oral and maxillofacial surgery/radiology
- Mobile units
- Facilities that do not discharge any amalgam process wastewater to a POTW (e.g., City of Brentwood sewer system) such as those that collect all process wastewater and transfer off-site for treatment
- Facilities that do not place or remove dental amalgam except in limited emergency or unplanned, unanticipated circumstances
Dental offices must install and maintain amalgam separators that are compliant with any of the following:
- American National Standards Institute (ANSI) American National Standard/American Dental Association (ADA) Specification 108 for Amalgam Separators (2009) with Technical Addendum (2011) (ANSI/ADA 108-2009)
- International Organization for Standardization 11143 Standard (2008) (ISO 11143)
- Subsequent versions so long as that version requires amalgam separators to achieve at least a 95% removal efficiency per 40 CFR 441.30(a)(2)(i-iii) (equivalent amalgam removal devices)
Dental offices are also required to have maintenance and inspection records readily available for inspection. Existing non-compliant amalgam separators must be replaced with one of the above after their useful life has ended, and no later than June 14, 2027
Best Management Practices (BMPs)
Dental offices are subject to, at a minimum, two BMPs:
- Waste amalgam including, but not limited to, dental amalgam from chair-side traps, screens, vacuum pump filters, dental tools, cuspidors, or collection devices, must not be discharged to a POTW
- Dental unit water lines, chair-side traps, and vacuum lines that discharge amalgam process wastewater to a POTW must not be cleaned with oxidizing or acidic cleaners, including but not limited to bleach, chlorine, iodine, and peroxide that have a pH lower than 6 or greater than 8 (i.e. cleaners that may increase the dissolution of mercury).
One-Time Compliance Form
Dental offices are required to submit a one-time Dental Dischargers Compliance Form
to their pretreatment Control Authority (e.g. City of Brentwood). This form certifies a dental office's compliance with the amalgam separator and BMP requirements.
- Dental offices that existed prior to July 14, 2017 must submit this form by October 12, 2020 (40 CFR Part 441.30).
- New dental offices that opened after July 14, 2017 must submit this form no later than 90 days following wastewater discharge into the City of Brentwood sewer system (40 CFR Part 441.40).
- If a dental office transfers ownership of the facility, the new owner must submit this form no later than 90 days following the transfer (40 CFR Part 441.50(a)(4)).
Dental offices are also required to maintain a copy of this form and have it readily available for an inspection.
Dental Dischargers Compliance Form
EPA Dental Fact Sheet
EPA Dental Category FAQ
Dental Amalgam BMPs (ADA)