Written and maintained by CASRAI Editorial Board
Last updated
General regulatory information for clinic and facilities staff, not legal or medical advice. Sources checked 2026-10-31.
Short answer
A dental amalgam separator is a device that captures amalgam particles from dental chair wastewater before it reaches the sewer. Under the US EPA’s dental effluent rule (40 CFR Part 441), dental offices that place or remove amalgam must operate and maintain one and must not discharge scrap amalgam. The separator must meet ISO 11143 or ANSI/ADA Specification 108 and achieve at least 95% removal efficiency.
Definition and scope
Amalgam is a mercury-containing dental filling material. When it is placed or removed, particles enter chair-side vacuum and wastewater lines. The EPA promulgated its dental effluent guidelines in 2017 to reduce the mercury that dental offices send to publicly owned treatment works (POTWs). The EPA estimates that about 103,000 dental offices use or remove amalgam and that almost all discharge to POTWs; it expects the rule to reduce mercury discharges by about 5.1 tons a year, along with 5.3 tons of other metals (EPA, Dental Effluent Guidelines, checked 2026-10-31). For background on why mercury is a concern, see the CASRAI guide why mercury is dangerous.
How the rule applies in practice
The operative text is 40 CFR 441.30 (checked 2026-10-31). The table below maps each requirement to its paragraph, so the checklist can be compared against a facility’s own records.
| Requirement | What 40 CFR 441.30 says | Paragraph |
|---|---|---|
| Performance standard | Separator complies with ANSI/ADA Specification 108 (2009, with 2011 addendum) or ISO 11143 (2008), or later versions, which require at least 95% removal efficiency, assessed by an accredited testing laboratory. | (a)(1)(i) |
| Sizing | Sized to accommodate the maximum discharge rate of amalgam process wastewater. | (a)(1)(ii) |
| Legacy units | A separator installed before June 14, 2017 satisfies the requirement until it is replaced or June 14, 2027, whichever is sooner. | (a)(1)(iii) |
| Inspection | Inspected in accordance with the manufacturer’s operating manual. | (a)(1)(iv) |
| Repair | A malfunctioning unit is repaired or replaced no later than 10 business days after the malfunction is discovered. | (a)(1)(v) |
| Retaining units | Units that retain captured amalgam are replaced on the manufacturer’s schedule or when they reach maximum level, whichever comes first. | (a)(1)(vi) |
| Alternative devices | A device other than a separator must remove at least 95 percent of the mass of solids, documented in a One-Time Compliance Report. | (a)(2) |
| Waste amalgam | Waste amalgam (chair-side traps, screens, vacuum pump filters, tools, cuspidors, collection devices) must not be discharged to a POTW. | (b)(1) |
| Line cleaners | Dental unit water lines, chair-side traps and vacuum lines must not be cleaned with oxidizing or acidic cleaners (for example bleach or peroxide; pH below 6 or above 8). | (b)(2) |
Existing and new sources must also submit a one-time compliance report to their pretreatment Control Authority (EPA, checked 2026-10-31). For existing sources the compliance date in the regulation is July 14, 2020.
Types and related concepts
Separator, retaining unit and alternative device
The rule distinguishes a separator that meets the ISO or ANSI/ADA standard from a retaining unit (a unit that holds captured amalgam and is replaced on a schedule or at maximum level) and from a non-separator device that has to document at least 95 percent removal of solids mass. The paragraphs above set each of the three out; the regulation does not rank them.
Control Authority
The Control Authority that receives the one-time report varies by location. The EPA states that it is the state agency in Alabama, Connecticut, Mississippi, Nebraska and Vermont; elsewhere it may be an EPA region, a local utility or a state Pretreatment Coordinator.
Where it matters for labs, clinics and supply decisions
Two points in the rule bear on equipment records. First, the standard is the check: a separator is specified by its ISO 11143 or ANSI/ADA 108 compliance as assessed by an accredited testing laboratory, and the regulation sets the 95% figure, not any individual product claim. Second, the legacy-unit date is a planning date: a unit installed before June 14, 2017 meets the requirement only until it is replaced or June 14, 2027, whichever is sooner. Unit inspection and retaining-unit replacement follow the manufacturer’s manual, so the manual is part of the compliance record. For related waste-classification and lab-safety background, see hazardous waste determination and the chemical hygiene plan entry for the wider framework. Labs that keep mercury-containing materials may also want the guide on chemical spill kits.
Common misunderstandings
- “The US does not regulate amalgam release.” It does: 40 CFR Part 441 applies to dental offices that discharge to POTWs.
- “A separator covers everything.” The rule also prohibits discharging waste amalgam from traps, screens and filters, and restricts the cleaners used on lines.
- “Any installed unit is fine indefinitely.” Pre-June 14, 2017 units have an end date, and any unit must be inspected and repaired within the stated limits.
- “Cleaning lines with bleach is harmless.” Oxidizing or acidic cleaners are specifically barred for these lines.
FAQ
Is an amalgam separator required?
Yes, for dental offices that place or remove amalgam: the EPA states they must operate and maintain an amalgam separator and must not discharge scrap amalgam. Non-separator devices are allowed only with documented removal of at least 95 percent of solids mass.
What standard must it meet?
ANSI/ADA Specification 108 (2009, with 2011 addendum) or ISO 11143 (2008), or later versions requiring at least 95% removal efficiency, assessed by an accredited testing laboratory (40 CFR 441.30(a)(1)(i)).
Do older separators need replacing?
A separator installed before June 14, 2017 meets the requirement until it is replaced or June 14, 2027, whichever is sooner (40 CFR 441.30(a)(1)(iii)).
What cannot go down the drain?
Waste amalgam from chair-side traps, screens, vacuum pump filters, tools, cuspidors and collection devices must not be discharged to a POTW, and lines must not be cleaned with oxidizing or acidic cleaners (40 CFR 441.30(b)).
Who receives the compliance report?
The facility’s pretreatment Control Authority, which differs by state or utility (see above).
Sources
- US EPA, Dental Effluent Guidelines, checked 2026-10-31.
- Legal Information Institute, 40 CFR 441.30, Pretreatment standards for existing sources (PSES), checked 2026-10-31.
