Medical Facilities

Best Management Practices For

Hazardous Materials/Waste Handling

(Updated 9/21/06)

 

Best Management Practices (BMPs) should be thought of as “good housekeeping” procedures. In medical facilities there are many waste streams that could be considered non-hazardous if properly recycled instead of thrown into the trash or dumped down the drain.

 

To the right of the waste heading you will find references to the respective federal and state law. Federal laws for waste management can be found in the Resource Conservation and Recovery Act (RCRA) - 40 Code of Federal Regulations (CFR) 260-266, 268, 270-273, 279, 280-282, and 148. State laws for waste management can be found in Florida Administrative Code (FAC) 62-730 and various Florida Statutes (F.S.). State laws on waste management are typical more stringent than federal laws.

 

Silver Recovery: [40 CFR 261 & 40 CFR 262 | FAC 62-730.030 |  F.S. 403.721] and [40 CFR 401 | FAC 62-660 | F.S. 403.051]

 

Depending on the locations of facilities and the pre-treatment requirements, you may be allowed to dispose of the photo processing liquid waste stream into the sanitary sewer. Silver is the regulated element in this waste stream and can be removed and sold. Below are some guidance suggestions for your use in determining BMPs for the facility. Each facility’s needs will depend on location and amounts processed each day.

 

GENERATION SOURCES AND DISPOSAL OPTIONS 

 

Silver is the element used as the light-sensitizing agent in most photographic materials and is present in photographic fixer solutions as silver thiosulfate complex. The speed, color and image quality is determined by the quantity of silver used in fabricating the film.  During the developing process, silver is released in the fixer and the bleach/fix.  In addition, silver is also present in the wash water as a result of “drag off” from the different processing tanks. Bleach solutions from black and white reversal processing contain silver as soluble silver sulfate, and can also have significant amounts of chromium as dissolved dichromate or chromic ion.  The concentration and distribution of silver in the photo processing solutions depends on the type of photo processing system used, method of collection, type of wash, and the amount of film processed per day.

 

Eventually, the solutions must be replaced and used solutions disposed of.  One method of disposal is the used solutions should be stored in containers (DOT approved) and hauled away by licensed commercial hazardous waste haulers. Another possible disposal method is to discharge the solutions to a POTW (Publicly Owned Treatment Works) also known as the sanitary sewer system. If the film processor elects to discharge the “waste” chemicals to a POTW, they must be treated to reduce the silver content prior to discharge. It is required that you receive written permission from your POTW’s “pretreatment officer” to discharge this type of waste stream. The pretreatment officer will approve or disapprove your request based on silver content of the waste, their operational permit requirements and the plants capacity for this type of waste stream. They can require pretreatment which is silver removal from the waste to get the waste to their acceptable limit. Discharges to a septic system will require approval from the Lee County Health Department and may not be attainable. This type of disposal is not recommended because of the potential to contaminate onsite property and because these chemicals may destroy the biological process necessary for septic tanks to continue effective operation.  It is important you know the difference between a POTW and an onsite septic system in order to meet the requirements for proper disposal. All records for disposal or recycling must be kept on site for three years.

 

Several silver recovery treatment technologies have been developed because of various factors. Disposal methods and variables such as geographical location (sewer district) and hazardous waste generator classification, of a particular photo-processing lab.  Selection of the appropriate method depends on the size of the processing facility, the amount of film processed, the waste disposal or discharge requirements, and the capital available for equipment procurement. Recovering silver provides an additional benefit of being a product to sell.

 

Methods of Reducing the Volume of Effluent Processed

 

1.      Use film-processing chemicals which require the least amount of liquid overflow, and have the lowest replenishment rate.  Check the manufacturers data sheets and make comparisons to determine which chemicals will provide the optimum usage time and the least amount of rinse water.

 

2.      Use counter current rinsing, rather than fresh water at each stage to reduce the amount of discharge.  The solutions should be tested frequently to ensure proper chemical content.  To increase the effectiveness of this technique, it may be advisable to use squeegees to minimize carryover of contaminants into each rinse stage.

 

3.      Cover processing tanks to reduce evaporation, and subsequent need to reconstitute the solution.

 

4.      To reduce the possibility of introducing additional silver into the process solutions or the effluent, thoroughly clean the system, drain lines, sumps, etc. to remove any buildup of deposits which have accumulated over the years.

 

5.      Monitor the effluent to the drain frequently and consistently, keep records of the observations.  Send samples of all solutions to an independent testing lab to ensure an accurate analysis for your process.

 

Methods of Measuring the Presence of Silver in Fixer Solutions

 

1.      Metal Replacement on Copper - A clean copper strip is dipped into the fixer effluent, if silver is present, the copper will change color.  This method does not indicate the quantity of silver in the solution, only that silver is present.  Experienced users, however, are able to judge the relative content based on the appearance of the silver on the copper strip.  Material cost is about $1 per test and can be purchased from any metal supplier.

 

2.      Silver Test Papers - The fixer effluent will cause the test strip to change colors, depending on the silver content of the fixer.  This test is somewhat more comprehensive than the Metal Replacement on Copper test, because of a direct correlation between distinct color changes and silver content in the solution.  Material cost is about $2 per test; test papers can be purchased in photo supply shops.

 

3.      Titration - This test is used to precisely measure the silver content of the fixer, and must be conducted in a laboratory by a trained technician.  Cost per test runs $18-$50.

 

4.      Atomic Absorption Spectrophotometry - A very precise method for measuring the silver content of the fixer; used only by larger processors with extensive laboratory facilities.  If the solution is sent to a laboratory for testing, the cost per test is $20-$60.

 

Silver Recovery Methods

 

1.      Metallic Replacement -This process consists of passing the fixer or bleach-fix, which contains silver through a relatively inexpensive cartridge, which is filled with steel wool.  The silver is recovered as sludge.  Metallic replacement occurs when the silver solution comes in contact with iron (steel wool).  The iron goes into a solution as a dissolved ion, and the silver is reduced to its metallic state and drops to the bottom as a sludge.

 

The metallic replacement method is particularly suited to smaller processors due to its low cost. The cartridges are available from several sources, are easy to install and require low maintenance. Other advantages of this process: no electrical power is required, silver concentrations in the effluent can be reduced to less than 5 mg/L.

 

2.      Electroplating - The fixer is passed through a unit which electrolitically causes the silver in the solution to be plated to cathode as essentially pure silver.  The remaining solution may also require further processing by the Metallic Replacement method if residual silver is present.

 

There are two basic techniques for installing an electroplating system.  A recirculating type of equipment is installed to allow the fixer to pass through the unit on a continuous basis, and the recovered solution is reused, or a system processes the fixer outside the loop.  Both electroplating methods of silver recovery require the use of considerably more costly equipment than the metallic replacement method.  In addition, electrical power which is converted to direct current is required to activate the system.

 

3.      Ion Exchange - Very effective recovery of silver from dilute solutions such as wash water, but it cannot be used to recover silver from fixer or bleach-fix.  The solution is initially pumped through a column of anion-exchange resin.  Further processing is required to recover the silver from the resin by electroplating or precipitation methods.  The Ion Exchange method is used primarily where silver discharge must be strictly limited and requires costly equipment.

4.      Evaporation / Distillation - Water is removed from the solution by evaporation, leaving the solid residue behind for disposal or recovery.  The evaporated water can be recovered by condensation and disposed of to the POTW or reused

5.      Chemical Precipitation - Metallic silver and insoluble silver compounds can be precipitated from photo processing solutions with chemical reagents such as sodium borohydride and sodium sulfide.  This method of recovering silver requires relatively inexpensive equipment, and is used primarily by manufacturers of photographic supplies, rather than by photo processors.

 

6.      Reverse Osmosis / Ultraflltration - The solution is forced through a semi-permeable membrane under pressure.  The water passes through the membrane, while silver and other dissolved species are collected on one side of the membrane.  The sludge containing the silver can be disposed of as hazardous waste, or processed further to recover the silver for resale.

 

Lead Foil Packaging: [40 CFR 261 & 40 CFR 262 | FAC 62-730.030 |  F.S. 403.721]

 

The lead foil backing on x-ray film needs to be recycled, not thrown into the trash.  If the foil backings are not recycled, they are considered a hazardous waste.  Some of the film suppliers will provide a recycling service; you should contact your supplier to explore your options.  All records for disposal or recycling must be kept on site for three years.

 

Amalgam:   [40 CFR 273.13 | FAC 62-737 | F.S. 403.7186] OR [40 CFR 261 & 40 CFR 262 | FAC 62-730.030 |  F.S. 403.721]

 

Dental amalgams are the silver colored fillings used to fill cavities. This substance is regulated because it contains the elements Mercury, Silver, and Tin.  Amalgam comes in different forms:  excess amalgam from new fillings, pulled teeth with amalgam fillings, and amalgam traps.  All of these may NOT go into the trash and MUST be recycled.  If you choose not to recycle your scrap dental amalgam, you must comply with all hazardous waste regulations.  All records for disposal or recycling must be kept on site for three years.

Additional Information on Amalgam Waste

 

Thermometers: [40 CFR 273.13 | FAC 62-737 | F.S. 403.7186]

 

Thermometers containing mercury should not be thrown into the trash.  A typical thermometer can contain .5-3 grams of mercury.  The mercury MUST be recycled.  This can be done by finding a hauler or using the Business Collection Days.  Thermometers should not be broken.  If one happens to break, place all mercury and glass into a closed container for proper disposal.  Do not use bare hands or a regular vacuum to

clean up mercury; this is hazardous to your health.  Less hazardous options for thermometers are alcohol filled or digital.  All records for disposal or recycling must be kept on site for three years.

 

Disinfectant waste: [40 CFR 261 & 40 CFR 262 | FAC 62-730.030 |  F.S. 403.721]

 

Most of the solvent waste generated at medical facilities come from the disinfectant or cleaning of instruments.  Depending on the concentration of the solution you are using, the waste may be hazardous.  Reading the Material Safety Data Sheet for your disinfect will determine your disposal method.  If the waste is hazardous, it must be captured in a container that is sealed so no evaporation occurs and treated as hazardous waste.  All records for disposal or recycling must be kept on site for three years.

 

Fluorescent Bulbs: [40 CFR 273.13 | FAC 62-737 | F.S. 403.7186]

 

Fluorescent bulbs/devices are considered hazardous waste because they contain the element Mercury.  However, if you recycle your Fluorescent bulbs/devices, they do not qualify as hazardous.  Caution: if a supplier tells you that their bulbs are environmentally safe remember that they are trying to sell you a product, and they may not be familiar with the State and Local regulations that pertain to the proper recycling or disposal of these mercury-containing bulbs. Lamps or devices with ANY mercury MUST be recycled.   All records for disposal or recycling must be kept on site for 3 years.

Additional Fluorescent Tube Information

*Material Safety Data Sheets are a good start to determine if your waste stream will be hazardous waste. They do have their limitations if they are too vague. MSDS’s do not take into account what process or system the product may be used in or what your management practices are for preventing cross contamination. Before purchasing any product, request the MSDS to see what is in it and to help avoid costs associated with the purchase, use, and disposal of the product.

 

Do not store any materials/waste near storm drains, ditches, creeks, rivers, canals or any bodies of water that would be contaminated if a spill occurs.

 

Do not throw away or send receipts that show proper disposal of waste materials to a bookkeeper.  They are required to remain on site for a minimum of three years.  This includes contracts with hazardous waste haulers.

 

Do not take the word of any sales person who will not supply MSDS for the product he/she is selling.  Some will say that the material is biodegradable or environmentally friendly, but the process that you use the material in may contaminate the product and cause it all to be regulated (i.e., equipment degreasing and rinsing).

 

Do not dispose of any material into your septic system, sanitary sewer, or storm sewer.  If you want to do this you must have written permission from the regulatory agency that permits that particular system. For Septic Systems it is the Department of Health and Rehabilitative Services; For Sanitary Sewers it is the local utility district that you are located within.

 

 

Do not store hazardous waste out of containment areas.  Make sure all containers are labeled properly (include dates where necessary).

 

If you have any questions, please call the Pollution Prevention Program at

(239) 652-6126.  We are here to serve your interest in the proper management of hazardous waste.