How to Safely Repair a Broken Mercury Thermometer: A Step-by-Step Guide

Mercury thermometers, once a staple in homes and laboratories, are now less common due to safety concerns surrounding mercury exposure. However, many older thermometers remain in use, and accidental breakage can still occur. While professional disposal is always the safest option, this guide provides detailed steps on how to *carefully* contain and potentially salvage a broken mercury thermometer at your own risk. **It is crucial to emphasize that handling mercury is dangerous, and proper precautions are essential to minimize health risks.** If you are uncomfortable with any of these steps, or if the spill is large or in a difficult-to-reach area, contact your local health department or hazardous waste disposal service immediately. This guide assumes the breakage is minor and that the mercury is contained to a small area.

Disclaimer

Mercury is a toxic substance. This guide is for informational purposes only and should not be considered a substitute for professional advice. The author and publisher are not responsible for any injury or damage resulting from the use of this information. If you are pregnant, have pre-existing health conditions, or are concerned about mercury exposure, consult a medical professional. If a large spill occurs, evacuate the area immediately and contact emergency services. This guide focuses on broken fever or laboratory thermometers containing a *small* amount of mercury. Industrial thermometers and other mercury-containing devices require specialized handling.

Understanding the Risks of Mercury Exposure

Before attempting any cleanup, it’s essential to understand the dangers of mercury. Mercury exposure can occur through inhalation, ingestion, or skin absorption. Even small amounts of mercury can cause serious health problems, including:

• Neurological damage: Mercury can affect the brain, spinal cord, and nerves, leading to tremors, memory loss, irritability, and difficulty concentrating.
• Kidney damage: Prolonged exposure can impair kidney function.
• Respiratory problems: Inhaling mercury vapor can irritate the lungs and cause breathing difficulties.
• Developmental problems: Mercury exposure during pregnancy can harm the developing fetus.

The primary risk associated with broken mercury thermometers is the inhalation of mercury vapor. Mercury evaporates at room temperature, releasing odorless, invisible vapors into the air. This is why immediate and thorough cleanup is crucial.

Materials Needed for Safe Cleanup

Gather the following materials before you begin:

• Protective Gear:
  • Nitrile gloves: These are essential to prevent mercury from absorbing into your skin. Avoid latex gloves, as mercury can penetrate them.
  • Eye protection: Wear safety glasses or goggles to protect your eyes from splashes.
  • Respirator (highly recommended): A respirator equipped with a mercury vapor filter is the best way to prevent inhalation. If a respirator isn’t available, ensure excellent ventilation by opening windows and using a fan to exhaust air from the room to the outside. A basic dust mask is not sufficient.
  • Protective clothing: Wear old clothes that you can discard after the cleanup. A long-sleeved shirt and long pants are recommended to minimize skin exposure. Consider disposable shoe covers.
• Cleanup Supplies:
  • Cardboard or stiff paper: To gently sweep mercury beads together.
  • Flashlight: To help locate small mercury beads.
  • Eye dropper or syringe: To carefully collect mercury beads.
  • Sealed container: A glass jar with a tight-fitting lid or a heavy-duty plastic bag (double-bagged) to store the collected mercury and contaminated materials. Label the container clearly as “Mercury Waste – Hazardous Material.”
  • Duct tape: To pick up tiny mercury beads from surfaces.
  • Shaving cream and paintbrush (optional): To help collect mercury from textured surfaces.
  • Powdered sulfur (optional but highly recommended): Sulfur reacts with mercury to form mercuric sulfide, a less volatile and easier-to-manage compound. It’s available at some pharmacies or online.
  • Paper towels: For wiping surfaces (use sparingly).
  • Spray bottle with water (optional): To dampen surfaces and reduce mercury vaporization.
• Disposal Supplies:
  • Heavy-duty trash bags: For disposing of contaminated materials (double-bagged).
  • Contact information for your local hazardous waste disposal center: Essential for proper disposal of the collected mercury and contaminated materials.

Step-by-Step Guide to Repairing (Containing) a Broken Mercury Thermometer

Again, remember that “repairing” in this context means containing and mitigating the hazard, not necessarily restoring the thermometer to working order.

1. Prepare the Area and Yourself:
   • Isolate the area: Close doors to other rooms and prevent people and pets from entering the affected area.
   • Ventilate: Open windows and use a fan to exhaust air from the room to the outside. Do not use a fan that recirculates air.
   • Put on your protective gear: Nitrile gloves, eye protection, respirator (if available), and protective clothing are essential.
2. Locate the Mercury:
   • Carefully examine the area: Mercury breaks into small, shiny beads that can scatter easily. Use a flashlight to help you find them, especially in cracks, crevices, and carpets.
3. Contain the Mercury:
   • Gather the beads: Use a piece of cardboard or stiff paper to gently push the mercury beads together into a single mass. Avoid using a vacuum cleaner, as this will vaporize the mercury and spread it throughout the room.
   • Collect the mercury: Use an eye dropper or syringe to carefully suck up the mercury beads and deposit them into the sealed container.
   • For hard-to-reach areas:
     • Duct tape: Press duct tape onto surfaces to pick up tiny mercury beads. Fold the tape over on itself to seal the mercury.
     • Shaving cream and paintbrush: For textured surfaces like carpets or upholstery, apply a thin layer of shaving cream to the affected area. Use a paintbrush to gently work the cream into the fibers, capturing the mercury beads. Then, carefully scrape up the shaving cream and mercury mixture and place it in the sealed container.
   • Consider using powdered sulfur: Sprinkle powdered sulfur over the affected area. The sulfur will react with any remaining mercury to form mercuric sulfide, which is a less volatile and easier-to-manage compound. The mercuric sulfide will appear as a brownish-yellow or reddish stain. Sweep up the mercuric sulfide and place it in the sealed container.
4. Clean the Area:
   • Wipe surfaces: Use paper towels dampened with water to wipe down all surfaces that may have come into contact with mercury. Use paper towels sparingly to avoid spreading the contamination. Dispose of the used paper towels in the heavy-duty trash bags.
   • Avoid harsh chemicals: Do not use bleach or ammonia-based cleaners, as they can react with mercury to form toxic gases.
   • Vacuuming (use as a last resort and with extreme caution): If mercury has seeped into carpets or upholstery and cannot be removed by other methods, carefully vacuum the area using a vacuum cleaner with a HEPA filter. However, be aware that this will contaminate the vacuum cleaner, and it should be disposed of properly as hazardous waste. Seal the vacuum cleaner bag tightly in a heavy-duty trash bag.
5. Dispose of Contaminated Materials:
   • Place all contaminated materials in heavy-duty trash bags: This includes paper towels, gloves, protective clothing, duct tape, shaving cream mixture, and any other items that may have come into contact with mercury. Double-bag the trash bags and seal them tightly.
   • Contact your local hazardous waste disposal center: They will provide instructions on how to properly dispose of the collected mercury and contaminated materials. Do not dispose of mercury or contaminated materials in the regular trash.
6. Monitor for Lingering Vapors:
   • Consider using a mercury vapor analyzer: These devices can detect even trace amounts of mercury vapor in the air. If you suspect that mercury vapor is still present, contact a professional environmental cleanup company.
   • Observe for symptoms: Be aware of potential symptoms of mercury exposure, such as tremors, headaches, fatigue, and irritability. If you experience any of these symptoms, consult a medical professional.
7. Ventilate Thoroughly:
   • Continue to ventilate the area for several days to ensure that any remaining mercury vapor is dispersed.

What NOT to Do

Avoid these common mistakes when dealing with a broken mercury thermometer:

• Do not vacuum: Vacuuming will vaporize the mercury and spread it throughout the room.
• Do not sweep with a broom: This will also spread the mercury.
• Do not use bleach or ammonia-based cleaners: These can react with mercury to form toxic gases.
• Do not pour mercury down the drain: This can contaminate the water supply.
• Do not wash contaminated clothing in the washing machine: This will contaminate the washing machine and potentially spread mercury to other clothing.
• Do not ignore the spill: Mercury is a toxic substance and requires immediate cleanup.

When to Call a Professional

In some cases, it’s best to call a professional hazardous waste cleanup company. Consider professional assistance if:

• The spill is large: If the thermometer contained a significant amount of mercury, or if the mercury has spread over a large area.
• You are unsure about the cleanup process: If you are uncomfortable with any of the steps outlined in this guide.
• You are pregnant or have pre-existing health conditions: It’s best to avoid any potential exposure to mercury.
• The mercury is in a difficult-to-reach area: Such as inside walls, under floors, or in ventilation systems.
• You suspect that mercury vapor is still present after cleanup: Even if you have followed all the steps in this guide, mercury vapor may still linger.

Alternatives to Mercury Thermometers

The safest option is to replace mercury thermometers with safer alternatives, such as:

• Digital thermometers: These are accurate, easy to use, and mercury-free.
• Infrared thermometers: These can measure temperature without touching the skin.
• Alcohol thermometers: These contain a colored alcohol solution instead of mercury.

Conclusion

Dealing with a broken mercury thermometer requires caution and careful planning. By following the steps outlined in this guide and taking the necessary precautions, you can minimize the risk of mercury exposure and safely contain the spill. Remember, if you are ever in doubt, contact your local health department or a professional hazardous waste disposal service. Your health and safety are the top priorities.