Laboratory Chemical Waste Management Procedures


Proper chemical management is necessary to protect the health and safety of the University and surrounding communities and the environment. There are federal and state regulations that require all generators of chemical waste receive training and follow proper waste management and disposal procedures. These regulations have severe monetary and civil penalties associated with them. Between 1990 and 2004, over twelve million dollars in fines have been levied against University and Colleges for hazardous waste and other environmental violations, leading the EPA to question waste management at educational institutions.


Chemical waste is defined by the United States Environmental Protection Agency and by the Delaware Department of Natural Resources and Environmental Control. Definitions, management practices and compliance are outlined in 40 Code of Federal Regulations and the Delaware Rules Governing Hazardous Waste. All policies and practices developed by the University of Delaware are designed to meet or exceed these regulations and assure compliance.

University Policy 7-18 states that all University of Delaware personnel must manage all chemical and hazardous waste in compliance with these federal and state regulations and in accordance with procedures set up by the Department of Environmental Health & Safety.

Chemical waste is a broad term and encompasses many types of materials. Consult your Material Safety Data Sheet (MSDS), Product Data Sheet or Label for a list of constituents. These sources will tell you if you have a chemical waste that needs special disposal. To reduce its long-term liability, the University is proactive in managing all of its chemical waste in an environmentally sound manner. If there are any questions on whether a material must be managed through the chemical waste management program, contact EHS or call 831-8475.

Examples of Chemical Waste include, but are not limited to:

  • Unused and surplus reagent grade chemicals
  • Intermediates and by-products generated from research & educational experiments
  • Batteries
  • Anything contaminated by chemicals
  • Used oil of all types
  • Spent solvents - including water based
  • Mercury containing items
  • Photographic film processing solutions and chemicals
  • Pesticides
  • Non-returnable gas cylinders
  • Non-empty aerosol cans
  • Chemically contaminated sharps
  • Finely divided powders
  • Contaminated syringes, needles, GC syringes, razor blades, pasteur pipettes, pipette tips
  • Equipment and apparatus containing hazardous waste
  • Computer/electronic equipment
  • Toner cartridges
  • Ethylene glycol
  • Paints - both oil and latex
  • Fluorescent light bulbs
  • Light ballasts
  • Preserved specimens
  • Custodial and industrial cleaners
  • Uncured Resins(Phenolic, Epoxy, Styrene, etc....)
  • Dye and glazes
  • Degreasing solvents
  • Brake/Transmission/Power Steering Fluids


Liquid Chemical Waste

Once it is determined that chemical waste will be generated, a container must be selected prior to waste generation. For bulk solvent and aqueous liquid waste streams use a Low Density Polyethylene Nalgene container. These containers will be returned within a week to the lab and are available from most laboratory supply companies and the campus storerooms. Nalgene containers are compatible with most chemical wastes, but there are a few waste streams that should not be accumulated in these containers.

DO Not Use glass, plastic-coated glass or other re-used reagent chemical bottles to store or accumulate bulk liquid chemical waste.

Examples of chemical that should not be stored in Nalgene containers:

  • Amyl Chloride
  • Bromine
  • Butyric Acid
  • Carbon disulfide
  • Nitrobenzene
  • Sulfur Dioxide
  • Thionyl Chloride
  • Vinylidene Chloride

Certain types of Nalgene containers work best for DEHS' operations. Please try to purchase containers that meet the following requirements:

  • Low density polyethylene
  • Either a 53B or 83B screw cap
  • Containers with a large handle
  • Capacity no larger than 5 gallons

For bulk corrosive liquid waste streams, use the Justrite Safety Containers for Waste Disposal. These containers are specially designed for corrosive chemical waste and vent under emergency conditions. DO NOT store or accumulate bulk liquid corrosive chemical waste in any other container. Go to Liquid Corrosive Chemical Waste Management for more information on managing corrosive waste streams.

Do Not use containers that are old, dented, damaged, leaking or cracked. The container must be able to be capped, sealed or closed. The container must be compatible with the waste streams that will be placed in it. For example, do not use a metal container to store acids, do not use a glass container to store hydrofluoric acid, do not use glass or metal containers to store organic peroxides and do not use metal containers to store picric acid and solutions of picric acid. Do not use containers that can be confused with consumer commodities like soda bottles or milk jugs. Do not use metal containers for flammable liquid waste, unless proper bonding and grounding precautions are taken.

Laboratory Clean Out of Regent Chemicals

All laboratories should, based on the hazards they pose, inspect all of their reagent chemicals. Look for chemicals that are no longer needed, old and out of date or unusable. Try to redistribute unneeded chemicals around the department or building. If no one else needs the chemical or if they are out of date or unusable, then package them as follows for disposal through DEHS:

  • Package by hazard class in sturdy cardboard boxes. Go to Chemical Storage for guidance on packaging by hazard class.
  • Use sufficient packing material to prevent container damage en route.
  • Place a completed chemical waste label and packing slip on the outside of the box.

Sample Vials - Sealed 15 ml or less

Some laboratories generate a number of sealed sample vials. If the laboratory does not want to reuse the glassware or plasticware and does not want to empty the contents into a liquid chemical waste container, the following procedures must be used:

  • Obtain a clean 5-gallon polyethylene pail with lid.
  • Line the pail with a heavy-duty plastic bag.
  • Place a chemical waste label on the outside of the pail.
  • Place only compatible material in pail. Go to Chemical Storage for guidance on compatibility.
  • Place the lid on the pail.
  • When full, tightly seal bag with tape or bag closure tie.

Solid Waste Streams

Solid waste includes any laboratory material that has come in contact with a chemical or is potentially contaminated with a chemical. Examples include gloves, bench-top paper, weighing boats and papers, paper towels, clean up material and permanently contaminated glassware and plasticware. Go to Laboratory Solid Waste Disposal Procedures for a flow chart that helps decide if a material requires management as chemical waste or if it can be placed in the normal trash. Use the following procedures to manage solid chemical waste:

  • Use five-gallon poly pails, cardboard boxes, or other sturdy containers.
  • All containers must have lids.
  • Apply a completed chemical waste label on the outside of the container or in vinyl tags attached to the containers.
  • Line the container with a 7-mil polyethylene bag or three standard trash bags.
  • All bags must be sealed unless laboratory personnel are actively adding waste. Seal the bag with a bag closure tie or a large binder clip.
  • When the container is full, seal the bag with tape. If the container is in a cardboard box, secure the box with tape as well.
  • It is important not to overload containers. Full boxes should not weigh more than 40 pounds. Do not use overly large boxes. Only fill boxes two-thirds full if they contain broken glass.

Chemically Contaminated Sharps

Anything that is capable of cutting or puncturing must be managed in a sharps container. Examples of sharps include needles, syringes, razor blades, slides, scalpels, pipettes, broken plastic or glassware, micropipettes and pipette tips. Sharps containers are available free of charge from DEHS. Go to Sharp and Piercing Object Disposal for more information about sharps management. If a sharp is chemically contaminated, simply place it in a sharps container that is labeled with a properly filled out Orange Chemical Waste Label.

Empty Chemical Containers

Empty chemical containers are still hazardous to the University personnel and the environment until they are properly managed. Go to Glass Only Disposal/Empty Chemical Container Disposal Procedures for complete information on empty container management. Below is a summary of the steps required to make empty chemical containers safe for disposal:

  • Triple rinse with copious amounts of water. Collect the first rinse as chemical waste. Rinse two and three can go down the sanitary sewer.
  • Place a label over the original container label or deface the label.
  • Do not replace the cap on the container.
  • Place empty/triple rinsed containers in a glass only box, recycling container or directly into the dumpster.

Clean, Uncontaminated Broken Glassware

In an effort to minimize the amount of chemical waste generated on campus, clean, uncontaminated glassware and plasticware should not be managed as waste. Unwanted clean non-broken glassware and plasticware can be packaged up by the laboratory personnel and taken to the dumpster or recycling area. Broken glassware and plasticware creates a potential hazard so special procedures are needed:

  • Purchase a glass only box from a campus storeroom or a laboratory supply company, or reuse a heavy corrugated cardboard box lined with a plastic liner.
  • Construct the box as per directions.
  • Tape the bottom.
  • When the container is 3/4's full, seal and take to the dumpster yourself. Remember that you must wear personal protective equipment (PPE) while handling these boxes. Minimum PPE includes leather work gloves and safety glasses. Custodial Services will not handle broken laboratory glassware and plasticware.

Gas Cylinders

The disposal of gas cylinders is extremely expensive. Unknown gas cylinders may cost in excess of $1,000 to identify and properly manage. Always check to make sure that all labels on gas cylinders are in good condition and legible. Contact the cylinder supplier and arrange a return if possible. It is best to use cylinders that will be returned. If lecture cylinders are required for research, use cylinders supplied by Aldrich, Matheson Tri Gas or Messer Gas. Disposal of Aldrich cylinders are inexpensive and Matheson and Messer Gas have a lecture bottle return program.

Gas Cylinder Resources:

MG Industries (800)-362-1221

Matheson (609)-467-2770

Recycling and Laboratory Wastes

Certain laboratory materials can be recycled while others cannot. Go to Campus Computer, Electronic Equipment and Office Supplies Recycling for complete information on recycling. Below is information specific for laboratories:

Laboratory materials that can be recycled:

  • Brown glass
  • Clear glass
  • Metal cans
  • Computer and electronic equipment

Laboratory materials that cannot be recycled:

  • Any glass bottles that are plastic coated
  • Pyrex
  • Glass only boxes


After you have determined what waste you are going to generate and have obtained the appropriate containers, you must properly fill out a chemical waste label and attach it to the containers. Chemical waste labels are available from DEHS, free of charge. There are directions on the back side of the label and labels must be applied on all chemical waste containers as soon as waste is added. These labels are designed to meet the regulatory requirements, therefore, every piece of information on the label is critical and must be completed.

How to Label:

  • The generator is the person who is filling out the waste label, not the lab group or Principal Investigator (PI) unless the PI is filling out the waste label.
  • Date the label with the date that the waste is first added.
  • Fill in building, room number and telephone number where the person who is filling out the waste label can be reached.
  • Circle the appropriate waste steam(s) or write it in.
  • List each waste constituent down to 1%; heavy metals must be listed down to the parts per million range. Label contents must add up to 100%. Volumes are acceptable.
  • Use only common chemical names or IUPAC nomenclature when listing the chemical constituents on the label.
  • Do not use:
    • Abbreviations
    • Chemical symbols
    • Trade names
  • Check the appropriate boxes for the waste stream.
  • If this waste is being moved to a Central Accumulation Area such as the Brown Solvent Shed, Colburn Solvent Shed or the McKinly Waste Storage Area, fill in the date that it is moved on the line at the bottom of the waste label.


Waste can be added only after you choose the proper container and it is labeled. The minimum personal protective equipment (PPE) may be dictated in the Chemical Hygiene Plan. If not, all personal working with chemical waste must wear the following:

  • Safety glasses
  • Splash goggles if working with liquid waste
  • Lab coat
  • Gloves specific for the compounds in use

Procedure for liquid chemical waste management:

  • Perform liquid chemical waste management in a fume hood. Mixing of liquid waste may generate toxic or corrosive aerosols.
  • Check the container label to assure that waste is being added to the correct container.
  • The container must be in secondary containment, i.e. large plastic bin or bucket.
  • Uncap the container.
  • Use a funnel sufficient for the size of the container and volume of waste being added.
  • Slowly add the waste, watching for any unintended reactions. If you observe a reaction, immediately stop adding the waste, close the fume hood sash and contact DEHS.
  • After the waste has been added, remove the funnel and seal the container with the cap.
  • Another option for liquid waste management is to use a specially designed waste funnel called ECO-Funnel. Go to Safety Ecological Funnels for more information.

Procedures for solid waste management:


Proper storage of chemical waste is extremely important. Explosions have occurred on campus that are attributed to improper storage of chemical waste. If you improperly label a container, other laboratory personnel unknowingly may add incompatible material to the container. For example, if an organic solvent solution is added to a container that is not labeled or labeled as an aqueous inorganic acid, and a fellow researcher may generate an inorganic nitric acid solution and add it to the container. Nitric acid and organic solvents are extremely incompatible and the container over a short period of time generates pressure and explodes. Go to Chemical Storage for guidance. Adhere to the following procedures on chemical waste storage to protect the health and safety of others, protect the University's facilities and to keep the University in compliance with all federal, state and local regulations:

  • Waste containers must remain closed or sealed at all times, except when waste is being added or removed from the container.
  • Liquid waste containers must be stored in secondary containment systems according to hazard class.
  • Store all bulk liquid waste containers in appropriate cabinets. DO NOT store bulk liquid chemical waste containers in fume hoods that have active experiments or reactions occurring.
    • Flammable Cabinets
    • Corrosive Cabinets
    • Under Fume Hood Cabinets
  • Do not allow excess accumulation of chemical waste to build up in your lab. Go to Hazardous Waste Definitions for more information on the limitations of waste storage.
  • Containers can only be filled to a maximum 90% full. Head space is needed for expansion and/or ease of dispensing.


All satellite chemical waste accumulation areas must be inspected on a weekly basis. This inspection does not have to be a formal inspection with documentation but laboratory personnel must inspect all chemical waste stored in their laboratories to assure the following:

  • There are no leaking containers of chemical waste.
  • All containers holding chemical waste are labeled with a completed orange chemical waste label.
  • All containers are sealed and closed. This includes waste containers holding solid chemical waste.
  • All liquid chemical wastes are stored in secondary containment bins.
  • Incompatible wastes are stored away from each other and in separate containment bins.
  • There is not an excessive accumulation of waste stored in the laboratory.Immediately correct any of the above if they are encountered during the course of the weekly inspection.


Certain departments and buildings have a Central Accumulation Area (CAA) set up in close proximity to their building. Laboratories in McKinly, Wolf, Brown, Lammot DuPont, Drake Hall, Colburn and Spencer should take their waste to the CAA. Go to Chemical Waste Removal Process for complete information on the CAA's.

Once a chemical waste container is full, DEHS should be contacted to remove the container or it should be moved to the CAA. In addition, if a chemical waste container has been in a laboratory for more than a year, it should be removed. If your building does not have a CAA, follow the procedure below:

  • You can request a chemical waste pick-up via the DEHS Web Page. Go to Chemical Waste Pick-Up Form and complete the web form. If you do not have access to a computer or if the web form does not work, contact EHS at 831-8475. We strongly encourage everyone to use the web form. This assists DEHS with complying with certain federal and state Regulations and tracking programs.
  • DEHS will only remove waste that is properly labeled and in a satisfactory container. If the container is not labeled or satisfactory, an attempt will be made to find the laboratory personnel to correct the problems. If no one can be located, the container will be left and DEHS will send an email to the responsible parties notifying them that the container was not removed.
  • Contact EHS directly or 831-8475 if you have a large or non-routine chemical waste pick-up.

Common Violations Found in Laboratories

DEHS routinely encounter a group of common problems and issues with chemical waste. These common problems are listed below with suggestions to prevent them from occurring. The EPA has fined Universities and Colleges for the problems listed below. Your support in eliminating these problems will greatly reduce the University's liability.

  • Unknown / Unlabeled chemical waste is very difficult and expensive to dispose of and poses an unnecessary risk to laboratory personnel as well as University personnel handling the waste. Unlabeled containers are a direct violation of the Federal and State hazardous waste regulations. Typically, DEHS covers the cost of all wastes generated by academic departments and programs. Departments generating unknown wastes may be charged for its disposal because of the extreme costs.
    • Prevention - Label all chemical waste with an orange chemical waste label. Update the constituents on the label every time waste is added. Inspect waste on a weekly basis to assure that containers are labeled and that the labels are in good condition. Inspect your chemical reagents to assure that the labels are still attached. Tape or replace as necessary.
  • Mixing or storage of incompatible chemicals may result in an explosion, fire or generation of toxic aerosols, vapor or fumes.
    • Prevention - Having an accurate, up-to-date waste label on each container will greatly reduce the possibility of mixing incompatible materials. Store incompatibles away from each other and in separate secondary containment bins.
  • Chemical containers that are left uncapped / open - This is a direct violation of Federal and State chemical waste and air permitting regulations and must not occur
    • Prevention - Seal all containers immediately after waste is added. Inspect accumulation areas to assure all containers are sealed. Purchase and use ECO-Funnels.
  • Laboratory personnel that are inadequately trained in the proper management of chemical waste - This is a direct violation of Federal and State chemical waste regulations. Additionally a lack of training places University Personnel, facilities and the environment at risk.
  • Liquid containers stored outside of secondary containers - If container(s) fail, the contents may migrate and commingle with incompatible chemicals or migrate to floor or sink drains. This is a direct violation of the Federal and State chemical waste regulations.
    • Prevention - Store all liquid chemical waste in secondary containment.
  • Waste Containers Stored In and/or Near Sink Areas and Floor Drains - If containers leak the contents could discharge down the drain. If this occurs, it is a direct violation of the Federal and State chemical waste and safe drinking water regulations.
    • Prevention - Store all liquid chemical waste in secondary containment and away from all floor and sink drains.


Proper chemical waste management protects the health and safety of everyone and prevents or minimizes pollution. All generators of chemical waste should do their best to minimize the amounts or chemical waste they generate and recycle whenever possible. Please contact EHS or call 831-8475 with any questions regarding chemical waste.