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AN EVALUATION OF AMALGAM SEPARATORS
ADA
PROFESSIONAL
PRODUCT
REVIEW
EXECUTIVE
SUMMARY
Professional Product Review A Publication of the Council on Scientific Affairs EXECUTIVE SUMMARY Read full report at www.ADA.org/ppr Section editor’s note: The ADA Professional Product Review is an online publication, with an executive summary that appears in The Journal of the American Dental Association. For the online version of Volume 7, Issue 2, containing the full text of the articles summarized here as well as additional content, please visit www.ada.org/ppr. —David C. Sarrett, DMD, MS, editor, ADA Professional Product Review, and JADA section editor, ADA Professional Product Review Executive Summary
AN EVALUATION OF AMALGAM SEPARATORS
Hwai-Nan Chou, MS; Julia Anglen, BS, BA n 2010, the U.S. Environmental Protection Agency (EPA) announced its intention to propose a rule to reduce mercury waste produced by dental offices. The agency intends to focus its technology assessment on amalgam separators and is preparing a regulatory proposal for review.1 Amalgam separators are devices designed to capture amalgam particles from dental office wastewater before it is discharged into the public sewer system. In anticipation of the EPA’s proposed rule, the ADA Laboratories purchased and evaluated nine separators available in the United States to determine their efficiency of amalgam removal. The devices evaluated involve the use of sedimentation technology, filtration technology or a combination of both. Amalgam waste comes from used amalgam capsules, unused scrap, chairside traps, vacuum pump filters and amalgam separator collection containers. Placing or removing amalgam restorations produces amalgam waste particles that can be suctioned into the dental unit vacuum line and, ultimately, discharged into the public sewer system. Separator systems capture amalgam particles
I
that are too fine to be removed by a chairside trap or a screen. The standard by which amalgam separators are most commonly evaluated is International Organization for Standardization (ISO) Standard 11143 for Amalgam Separators.2 The standard requires that an amalgam separator remove from the waste stream at least 95 percent of the amalgam particles. Results. Our results show that all nine amalgam separators passed the ISO 11143 requirement of 95 percent amalgam removal efficiency. Discussion. For evaluation purposes, manufacturers must state the maximum fillable volume (MFV) for their amalgam separator. ISO 11143:2008 defines MFV as the “level or volume defined by the maximum waste solids/sludge collecting capacity of the removable collecting container of the amalgam separator at which the efficiency is unaffected.”2 Only three amalgam separators had clearly marked MFVs and transparent collecting capsules that indicate when the amalgam sludge container has filled to capacity and requires maintenance. Three manufacturers provided MFVs that do not correspond with the values found in the ADA Laboratory evaluation. Two manufacturers reported MFV values that were higher than the values found experimentally, meaning these units need replacing sooner than the manufac-
Mr. Chou is manager of chemistry, Research and Laboratories, Division of Science, American Dental Association, 211 E. Chicago Ave., Chicago, Ill. 60611, e-mail [email protected]. Address reprint requests to Mr. Chou. Ms. Anglen is a research assistant, North Bridge Staffing, Chicago.
920
JADA 143(8)
http://jada.ada.org
August 2012
Copyright © 2012 American Dental Association. All rights reserved.
ADA
PROFESSIONAL
PRODUCT
turer indicates; one manufacturer reported an MFV that was less than that found experimentally, meaning this unit can be replaced later than indicated by the manufacturer. Seven of the amalgam separators tested had bypass mechanisms, which allow suction power to remain the same even when the collecting capsule is full. These mechanisms accomplish this by completely bypassing the collecting capsule and permitting unprocessed drainage to flow directly into the public wastewater system. The advantage is that dental operations will not be interrupted when the separator is full. However, this also means that the separator’s ability to remove amalgam particles is reduced—and with the suction unaffected, the dentist will not be aware that the separator needs maintenance, thus prolonging contamination of the wastePRACTICAL ISSUES FOR PURCHASING, INSTALLING AND MAINTAINING DENTAL AMALGAM SEPARATORS
Kevin R. McManus, MA, MBA ental offices are one of the most frequently referenced sources of mercury added to public sewer systems; their contribution comes in the form of dental amalgam. Environmental agencies continue to develop regulations, outreach programs or both on a state and local basis that encourage or, in some areas, require dental offices to install amalgam separators. A dental office’s waste infrastructure and office procedures can affect the choice of an amalgam separator. Dental teams also will encounter important differences in operating and maintaining separator units properly. Before purchasing or installing an amalgam separator, consider these factors: dspace requirements; dutility requirements; ddental office/building constraints; dease of maintenance and replacement; deffect on suction equipment; dpurchase, installation and maintenance costs. Space requirements. A separator’s performance relies, in part, on the equipment’s correct installation within the dental office’s existing wastewater and vacuum system. There generally are three distinct installation locations: directly within the vacuum system piping, or “in line,” at or near individual operatory chairs; in line at a central location upstream of the vacuum pump; or at the outlet side of the airwater separator.
D
REVIEW
EXECUTIVE
SUMMARY
water system. Two separators evaluated did not have a bypass mechanism, meaning their suction power will diminish gradually when the unit is filled to capacity. Conclusions. Although the test results show that all nine amalgam separators passed the ISO 11143 requirement of 95 percent amalgam removal efficiency, for proper use, purchasers and users of these devices should note the separator’s maximum fillable volume and bypass mechanism. ■ Disclosure. Mr. Chou and Ms. Anglen did not report any disclosures. 1. U.S. Environmental Protection Agency. Dental amalgam effluent guideline. http://water.epa.gov/scitech/wastetech/guide/dental/ index.cfm. Accessed June 29, 2012. 2. International Standards Organization. ISO 11143: Dentistry— Amalgam Separators. Cited in: American National Standards Institute and American Dental Association. Specification No. 108: Amalgam Separators. Chicago: American Dental Association; 2009.
Utility requirements. Many separators rely on gravity or the vacuum system for operation and do not require an electrical power source beyond that needed to power the vacuum system. However, some units need electrical power connections for the control panel or to operate pumps. Dental office/building constraints. Building factors that affect placement and installation of amalgam separators include building configuration, available installation space, access to centralized plumbing lines and amalgam separators, office space leasing agreements, plumbing code requirements and approved equipment lists. Building configuration. Centrally plumbed offices in which all plumbing systems drain into one pipe may need modification so that only drainage from amalgam-generating sources runs through the separator. Additional water flows (cuspidors, sinks and operatories used exclusively for hygiene appointments) can affect separator performance adversely. Installation space. Many dental offices install vacuum systems and air-water separators at the basement level to conserve office space. Offices with no basement or plumbing closet may require the use of chairside amalgam separators in individual operatories. Access to plumbing lines and amalgam separators. Suitable access is needed to allow for inspection and maintenance of the separator. Dental practices that share plumbing or vacuum systems will need to coordinate maintenance activities so as not to interfere with work schedules. Office space leasing agreements. Many JADA 143(8)
http://jada.ada.org
Copyright © 2012 American Dental Association. All rights reserved.
August 2012 921
PROFESSIONAL
PRODUCT
REVIEW
EXECUTIVE
SUMMARY
Professional Product Review A Publication of the Council on Scientific Affairs EXECUTIVE SUMMARY Read full report at www.ADA.org/ppr Section editor’s note: The ADA Professional Product Review is an online publication, with an executive summary that appears in The Journal of the American Dental Association. For the online version of Volume 7, Issue 2, containing the full text of the articles summarized here as well as additional content, please visit www.ada.org/ppr. —David C. Sarrett, DMD, MS, editor, ADA Professional Product Review, and JADA section editor, ADA Professional Product Review Executive Summary
AN EVALUATION OF AMALGAM SEPARATORS
Hwai-Nan Chou, MS; Julia Anglen, BS, BA n 2010, the U.S. Environmental Protection Agency (EPA) announced its intention to propose a rule to reduce mercury waste produced by dental offices. The agency intends to focus its technology assessment on amalgam separators and is preparing a regulatory proposal for review.1 Amalgam separators are devices designed to capture amalgam particles from dental office wastewater before it is discharged into the public sewer system. In anticipation of the EPA’s proposed rule, the ADA Laboratories purchased and evaluated nine separators available in the United States to determine their efficiency of amalgam removal. The devices evaluated involve the use of sedimentation technology, filtration technology or a combination of both. Amalgam waste comes from used amalgam capsules, unused scrap, chairside traps, vacuum pump filters and amalgam separator collection containers. Placing or removing amalgam restorations produces amalgam waste particles that can be suctioned into the dental unit vacuum line and, ultimately, discharged into the public sewer system. Separator systems capture amalgam particles
I
that are too fine to be removed by a chairside trap or a screen. The standard by which amalgam separators are most commonly evaluated is International Organization for Standardization (ISO) Standard 11143 for Amalgam Separators.2 The standard requires that an amalgam separator remove from the waste stream at least 95 percent of the amalgam particles. Results. Our results show that all nine amalgam separators passed the ISO 11143 requirement of 95 percent amalgam removal efficiency. Discussion. For evaluation purposes, manufacturers must state the maximum fillable volume (MFV) for their amalgam separator. ISO 11143:2008 defines MFV as the “level or volume defined by the maximum waste solids/sludge collecting capacity of the removable collecting container of the amalgam separator at which the efficiency is unaffected.”2 Only three amalgam separators had clearly marked MFVs and transparent collecting capsules that indicate when the amalgam sludge container has filled to capacity and requires maintenance. Three manufacturers provided MFVs that do not correspond with the values found in the ADA Laboratory evaluation. Two manufacturers reported MFV values that were higher than the values found experimentally, meaning these units need replacing sooner than the manufac-
Mr. Chou is manager of chemistry, Research and Laboratories, Division of Science, American Dental Association, 211 E. Chicago Ave., Chicago, Ill. 60611, e-mail [email protected]. Address reprint requests to Mr. Chou. Ms. Anglen is a research assistant, North Bridge Staffing, Chicago.
920
JADA 143(8)
http://jada.ada.org
August 2012
Copyright © 2012 American Dental Association. All rights reserved.
ADA
PROFESSIONAL
PRODUCT
turer indicates; one manufacturer reported an MFV that was less than that found experimentally, meaning this unit can be replaced later than indicated by the manufacturer. Seven of the amalgam separators tested had bypass mechanisms, which allow suction power to remain the same even when the collecting capsule is full. These mechanisms accomplish this by completely bypassing the collecting capsule and permitting unprocessed drainage to flow directly into the public wastewater system. The advantage is that dental operations will not be interrupted when the separator is full. However, this also means that the separator’s ability to remove amalgam particles is reduced—and with the suction unaffected, the dentist will not be aware that the separator needs maintenance, thus prolonging contamination of the wastePRACTICAL ISSUES FOR PURCHASING, INSTALLING AND MAINTAINING DENTAL AMALGAM SEPARATORS
Kevin R. McManus, MA, MBA ental offices are one of the most frequently referenced sources of mercury added to public sewer systems; their contribution comes in the form of dental amalgam. Environmental agencies continue to develop regulations, outreach programs or both on a state and local basis that encourage or, in some areas, require dental offices to install amalgam separators. A dental office’s waste infrastructure and office procedures can affect the choice of an amalgam separator. Dental teams also will encounter important differences in operating and maintaining separator units properly. Before purchasing or installing an amalgam separator, consider these factors: dspace requirements; dutility requirements; ddental office/building constraints; dease of maintenance and replacement; deffect on suction equipment; dpurchase, installation and maintenance costs. Space requirements. A separator’s performance relies, in part, on the equipment’s correct installation within the dental office’s existing wastewater and vacuum system. There generally are three distinct installation locations: directly within the vacuum system piping, or “in line,” at or near individual operatory chairs; in line at a central location upstream of the vacuum pump; or at the outlet side of the airwater separator.
D
REVIEW
EXECUTIVE
SUMMARY
water system. Two separators evaluated did not have a bypass mechanism, meaning their suction power will diminish gradually when the unit is filled to capacity. Conclusions. Although the test results show that all nine amalgam separators passed the ISO 11143 requirement of 95 percent amalgam removal efficiency, for proper use, purchasers and users of these devices should note the separator’s maximum fillable volume and bypass mechanism. ■ Disclosure. Mr. Chou and Ms. Anglen did not report any disclosures. 1. U.S. Environmental Protection Agency. Dental amalgam effluent guideline. http://water.epa.gov/scitech/wastetech/guide/dental/ index.cfm. Accessed June 29, 2012. 2. International Standards Organization. ISO 11143: Dentistry— Amalgam Separators. Cited in: American National Standards Institute and American Dental Association. Specification No. 108: Amalgam Separators. Chicago: American Dental Association; 2009.
Utility requirements. Many separators rely on gravity or the vacuum system for operation and do not require an electrical power source beyond that needed to power the vacuum system. However, some units need electrical power connections for the control panel or to operate pumps. Dental office/building constraints. Building factors that affect placement and installation of amalgam separators include building configuration, available installation space, access to centralized plumbing lines and amalgam separators, office space leasing agreements, plumbing code requirements and approved equipment lists. Building configuration. Centrally plumbed offices in which all plumbing systems drain into one pipe may need modification so that only drainage from amalgam-generating sources runs through the separator. Additional water flows (cuspidors, sinks and operatories used exclusively for hygiene appointments) can affect separator performance adversely. Installation space. Many dental offices install vacuum systems and air-water separators at the basement level to conserve office space. Offices with no basement or plumbing closet may require the use of chairside amalgam separators in individual operatories. Access to plumbing lines and amalgam separators. Suitable access is needed to allow for inspection and maintenance of the separator. Dental practices that share plumbing or vacuum systems will need to coordinate maintenance activities so as not to interfere with work schedules. Office space leasing agreements. Many JADA 143(8)
http://jada.ada.org
Copyright © 2012 American Dental Association. All rights reserved.
August 2012 921