Prevention and response procedures

Proper spill cleaning depends on the material's type and volume. Users can immediately clean up small spills of low-hazard materials. If you are unsure, contact EH&S at (515) 294-5359.

Larger spills or spills involving more hazardous items may require EH&S or Ames Fire Department assistance.

A properly stocked spill control kit shall be available in each laboratory. Spill kits are available at Central Stores or safety equipment suppliers. Ensure the spill kit location is marked with a sign (available from EH&S). In lieu of purchasing a kit, personnel may choose to assemble a kit. The spill control kit must contain appropriate neutralizers for acids and bases stored in the laboratory.

University personnel play a key role in protecting our waterways from chemical contamination. Spill kits should be maintained in laboratory spaces. Chemicals may not be poured or dumped into sanitary or storm drains, in garbage cans or dumpsters, or onto the ground.

Biohazardous material spill protocol

Each laboratory using biohazardous materials must have appropriate equipment and supplies on hand for managing spills and accidents. Keeping a biohazard spill kit (PDF) in your lab provides easy access to these items in case of a spill. The biological spill cleanup procedures (PDF) are intended for use with microorganisms handled at BSL-2 or lower. Questions about spill cleanup for the use of organisms handled at BSL-3 should be directed to the Biosafety Officer before work begins with the microorganism. If the biohazardous spill also includes radioactive material, the cleanup protocol may need to be modified. For these situations, the Radiation Safety Officer (during the regular work day) or the Department of Public Safety (after hours) can answer any cleanup questions. 

Any potentially contaminated clothing must be removed and placed in a biohazard waste bag for autoclaving. The laboratory must be evacuated immediately if the spill is outside a biological safety cabinet (BSC). The last person out is responsible for ensuring that all doors have been closed. The room must remain vacant with the door shut for at least 30 minutes to allow the laboratory ventilation system to clear any aerosolized material from the room, thus decreasing the risk of inhaling biohazardous materials.

  • If this spill is outside the laboratory, immediate cleanup is essential. If outdoors, personnel should remain upwind from the spill, if possible. 
  • If the spill is inside a centrifuge, the centrifuge should be closed as soon as the spill is noticed.  
  • If the spill is contained inside a BSC, the room need not be evacuated. However, the BSC must remain running. 
  • Hands and other contaminated skin must be washed thoroughly with soap and water. 
  • Everyone not needed for spill cleanup must be cautioned to avoid the spill area. Signs may be posted if necessary.
    • EH&S and DPS are available to assist with spills outside the laboratory.  If possible, laboratory personnel should appoint someone to call so they may remain and secure the site. 
  • Appropriate PPE must be worn.  At a minimum, disposable gloves, eye protection, and a lab coat should be worn.  An N95 dust mask respirator is advised for spills greater than ~10mL outside a BSC or any spill inside a centrifuge because of the likelihood of splashing and/or aerosolizing the biohazardous material. 
  • Any sharp contaminated objects must be removed from the spill area using mechanical means, never with hands. 
  • After all sharps are removed, disinfectant must be poured carefully around the edges of the spill with care taken to avoid splashing.  Paper towels can absorb as much of the spilled material as possible.  Working from the outside of the spill toward the center avoids spreading contamination. 
    • If the spill is inside a centrifuge, the rotor and its contents should be moved to a BSC. 
  • If the spill is inside a BSC, the cabinet should be left running for at least 10 minutes before resuming use. The spill tray underneath the work area and the trough below the air intake grill must also be cleaned. These are likely to be contaminated when the spill is large.
  • Alcohol is not recommended as a disinfectant for large spills, especially inside a BSC, because large amounts of alcohol pose an explosion hazard.
  • After initial cleanup, the spill area must be flooded with disinfectant and left to soak for at least 20 minutes (adequate contact time is important to ensure complete decontamination).
  • Disinfectant can be absorbed with paper towels. A final wipe-down should be done with clean paper towels soaked with disinfectant. Laboratory personnel should disinfect any equipment, walls, or other areas likely splashed by the spill.
  • All contaminated waste must be disposed of properly.
  • Hands must be washed thoroughly with soap and water.

Small chemical spill protocol

A small chemical spill is a volume which does not exceed the capacity of a standard spill kit (PDF). Note: Small chemical spill cleanup is the responsibility of the department. EH&S plays only a consultation role during small chemical spills. 

The following general procedures should be followed by laboratory personnel to clean up small spills:

  1. Notify people in the immediate area.
  2. Evacuate all nonessential personnel from the spill area.
  3. Attend to exposed or contaminated personnel by following the first aid procedures.
  4. If spilled material is flammable, turn off ignition and heat sources.
  5. Avoid breathing vapors of the spilled material and, if necessary, use a respirator (see Respirators).
  6. Maintain or establish exhaust ventilation, if safe to do so, by opening the sash on the fume hood. Do not open doors or windows.
  7. Wear appropriate personal protective equipment (PPE) such as gloves, lab coats, goggles, and aprons to prevent exposure and minimize contamination. 
  8. Obtain a laboratory spill kit.
  9. Using the absorbent material, confine the spill if this can be done without risk of injury or contamination.
  10. Remove sharp objects using mechanical means such as tongs; never with hands.
  11. Clean up the spill by working from the outside of the spill toward the center to minimize the spread of contamination.
  12. Neutralize or clean the spill area. Be sure to allow adequate contact time to ensure complete neutralization.
  13. Properly dispose of spill cleanup debris according to procedures outlined in the Waste and Recycling Guidelines Manual (PDF).
  14. Wash hands and other exposed skin after completing clean-up.
  15. Notify EH&S if you require assistance or additional information.

Large chemical spill protocol

In the event of a large chemical spill (i.e., a volume of chemical that exceeds the capacity of a standard spill kit, uncontrolled leakage of toxic or highly corrosive gas, or a situation in which readily available personal protective equipment (PPE) is inadequate to ensure worker safety), the following measures must be followed:

  1. Evacuate the area immediately, shutting doors and windows on the way out, if possible.
  2. Activate fire alarms (or chemical safety alarms if applicable) for situations that threaten life or property and immediately dial 911.
  3. Notify the laboratory supervisor, principal investigator and EH&S (515-294-5359; after hours contact ISU Police at 515-294-4428).
  4. Attend to any persons who may have been exposed or contaminated by following the first aid procedures.
  5. Assemble persons in the laboratory during the spill and wait for assistance at a safe location.
  6. Provide EH&S and/or fire & police officials with details of the problem upon their arrival.

If chemicals are spilled outside of buildings or released to a direct conduit, such as a floor drain, sink drain, or fume hood drain:

  1. Evacuate the area. Even inside a building, toxic vapors or reactions may erupt from a contaminated drain.
  2. Contact EH&S at (515) 294-5359 (after hours, contact the ISU Police at (515) 294-4428).
  3. Report the chemical name, quantity released, location, approximate time of the incident, and your name.
  4. EH&S will contact the appropriate regulatory agencies and initiate reporting if necessary.

Visit the Compressed Gas Safety page for the response procedures for minor and major leaks.

Due to its hazardous nature and the difficulty and time involved in cleanup, every effort should be made to prevent spills of metallic mercury. Globules can get into cracks and crevices, under table legs, and into and under equipment. When a spill occurs, the following procedures should be used during cleanup based on the spill's size.

Large spills

Mercury spills with a volume greater than a standard thermometer are considered large. If a large spill occurs, personnel should leave the area and contact EH&S at (515) 294-5359 to arrange for spill cleanup.

Note: Departments will be charged for spill cleanups performed by EH&S.

Small spills

Mercury spills with volumes equal to or less than those in a standard thermometer are considered small.

EH&S discourages using mercury sponges and sulfur or zinc powders to clean up spills. Amalgamated mercury cannot be recycled, and disposal is expensive. To eliminate potential contact with skin or clothing, appropriate protective equipment, such as that listed below, should be worn when working with mercury spills.

The following equipment should be assembled before cleanup initiation. (Central Stores numbers have been provided for some items.)

  • Nitrile gloves
  • Booties (#4692.0104)
  • Coveralls - optional (#4602.0317)
  • Polyethylene bottle
  • Vacuum device (see examples provided below)
  • Flashlight
  • Plastic waste bag and permanent ink marker


  • Personnel in the immediate area must be notified of a mercury spill.
  • Chalk, tape, or other means should be used to mark the spill boundary.
  • If the spill occurred on the floor, the extent of the spill should be determined, and the area should be isolated to avoid foot traffic in the contaminated area.
  • A standard vacuum cleaner should never be used to pick up mercury.
  • Pools and globules of mercury should be pushed together and collected by suction using a small glass pipette attached to an aspirator bulb or a vacuum device made from a filtering flask, rubber stopper, and several pieces of glass tubing.
  • Metallic mercury should be collected and placed in a sealed polyethylene bottle or vial.
  • Broken glass or other contaminated materials must be collected in a plastic disposal bag.
  • After an initial cleaning, and with the room lights off, the spill area should be checked using a flashlight near floor level. This will help reveal any remaining mercury.
  • Cleanup articles, such as shoe covers, gloves, or suits, should be sealed in a plastic bag and marked "Metal Mercury Hazardous Waste."
  • Hands, arms, and face must be thoroughly washed after completing cleanup activities.
  • To arrange the removal of waste mercury and mercury-contaminated articles, complete a Waste Removal Request.
  • Orange waste description tags must also be completed and attached to waste containers.

Despite strict adherence to all laboratory safety practices, it is possible for radioactive material contamination to occur. For this reason, it is important that radioactive material users are aware of the proper procedures to follow in the event of various contamination situations.

Minor spills

Incidents that involve the release of less than 100 microcuries of a radionuclide in a nonvolatile form can generally be considered minor. For minor contaminations, lab personnel should follow these steps:

  • Immediately notify all other persons in the lab.
  • Restrict the area to only those personnel needed to clean the contamination.
  • Confine the spill immediately.
  • Liquids: Drop absorbent paper or an absorbent chemical (calcium bentonite) on the spill to absorb free liquid. Decontaminate using a detergent solution, cleaning from the outside edges towards the center of the contamination.  Monitor the area as you clean.
  • Solids: Dampen thoroughly, taking care not to spread contamination. Use a detergent solution to clean unless a chemical reaction would release air contaminants; otherwise, use oil. Clean from the outside edges towards the center of the contamination.  Monitor the area as you clean.
  • Notify the laboratory supervisor.
  • Follow the Decontamination Procedures listed at the bottom of this page.
  • Notify EH&S by telephone: (515) 294-5359.

Major spills or large-volume releases

A release exceeding 100 microcuries of a radionuclide in a nonvolatile form, the release of any amount of a radionuclide in a volatile form, or the release of a large volume of material should be considered a "major" contamination event. In such cases, laboratory personnel should follow these steps:

  • Evacuate the room immediately, shutting doors and windows on the way out.
  • Notify the laboratory supervisor.
  • Immediately notify EH&S by telephone: (515) 294-5359, or, after hours, Department of Public Safety, telephone: (515) 294-4428.
  • Post a "Keep Out" sign on the laboratory door.
  • Assemble those persons in the laboratory when the spill occurred, but remain far enough away to assure everyone’s safety.
  • Wait for assistance and do not leave the area.

Accidents involving personal injury

Medical treatment or assistance will always be the first priority for any accident involving personal injury. This may involve administering first aid and/or calling 911 for emergency medical assistance. For accidents involving radioactive materials, contamination control and exposure control are important but should never delay or impede medical assistance. If radioactive materials are involved, emergency personnel should be notified before treatment takes place, so they can take appropriate action to protect themselves and prevent the spread of contamination. EH&S must also be notified as soon as possible. After the injured person is treated and removed from the accident site, the previously described procedures should be followed as appropriate.

Personal contamination

In the event of any personal contamination, laboratory personnel should follow these steps:

  • Immediately notify EH&S by telephone: (515) 294-5359, or, after hours, Department of Public Safety, telephone: (515) 294-4428. 
  • Remove all contaminated laboratory personal protective clothing (lab coat, gloves, etc.). 
  • Wash the contaminated area with mild soap and water if possible.
  • Monitor the contaminated area. Repeat washing as necessary.

Decontamination procedures

In the event that surfaces or equipment within the laboratory are suspected or determined to be contaminated with radioactive material, the radionuclide user must initiate and complete appropriate decontamination procedures. For most relatively minor contamination incidents, the following general steps should be taken upon discovery of the contamination:

  • Mark the perimeter of the contaminated area.
  • Notify EH&S of the contamination so that their staff can more accurately assess the extent of the contamination and advise and assist in the decontamination effort.
  • Assemble cleaning supplies (paper towels, detergent in water, plastic bags, and plastic gloves). Proceed with scrubbing the area from the borders to the center, cleaning small areas at a time.
  • Periodically monitor the effectiveness of the decontamination effort with surface wipes and portable instrument surveys. Place all contaminated cleaning materials, including paper towels, rags, and gloves, in a plastic bag and label as "radioactive waste."
  • Notify EH&S upon completion of the decontamination effort so that a follow-up contamination survey can be made.

Additional information on any of these procedures is available from EH&S at (515) 294-5359.