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A mercury spill kit is a packaged set of materials for cleaning up a small elemental mercury spill, typically one the size of a broken thermometer. A commercial kit and the improvised household list published by the U.S. EPA solve the same problem with different materials, and neither covers a large spill. This page lays the two side by side and shows where a kit stops. For the general laboratory kit, see chemical spill kits.
Purpose and setting
Elemental mercury beads roll, split into smaller droplets and lodge in cracks, which is why cleanup relies on materials that pick up or bind small beads rather than ordinary sweeping. Why the metal is a hazard is covered in why mercury is dangerous, and the thermometer case is in mercury in a thermometer. A kit exists to put the right materials and written instructions in one place before a spill happens.
One example of an institutional kit: Northwestern University Research Safety lists a Mercury Spill Kit containing Hg Absorb powder, an Hg Absorb sponge, shoe covers, a plastic waste bag, instructions and a mercury-free thermometer. Its page describes the kit as intended for small mercury spills, typically the size of a broken thermometer, and says to consult Research Safety for larger spills. Other kits differ in contents, so read the instructions for use that ship with the kit you hold.
Checklist: EPA improvised list and an example kit
The EPA page "What to Do if a Mercury Thermometer Breaks" lists the materials to gather for a household cleanup. The table sets them beside the example institutional kit above. Items are grouped by job.
| Job | EPA improvised list | Example institutional kit (Northwestern) | Note |
|---|---|---|---|
| Pick up beads | Stiff cardboard or a squeegee; an eyedropper; duct tape, or shaving cream and a small paint brush | Hg Absorb sponge | EPA names these as the tools for gathering beads. |
| Bind small residue | Powdered sulfur (optional), which EPA says binds small beads and is sometimes found in the gardening departments of hardware stores | Hg Absorb powder | Sulfur is optional on the EPA list. |
| Hand and foot protection | Disposable gloves (rubber, nitrile or latex) | Shoe covers | The EPA page lists gloves; the example kit page lists shoe covers. Neither list is a substitute for the other. |
| Wipe and contain | Paper towels; 4 or 5 resealable plastic bags | Plastic waste bag | EPA seals the glass and towels in a zip bag, and the brush and tape in a second one. |
| Waste bag | Heavy-duty trash bags, about 2 to 6 mil | Plastic waste bag | EPA puts cleanup materials, gloves and beads in a trash bag placed outside in a secured area. |
| Seeing beads | Flashlight or task light | Not listed on the page | A light helps show beads on the floor. |
| Written steps | The EPA page itself | Instructions | Quantities are set by the instructions that ship with the kit. |
| Thermometer replacement | Not listed | Mercury-free thermometer | The example kit supplies a replacement. |
What a kit does not cover
The EPA page sets out several things that no kit should be used to override:
- Never use a vacuum cleaner on mercury, because it puts mercury into the air.
- Do not use a broom, which breaks mercury into smaller droplets and spreads them.
- Never pour mercury down a drain; it lodges in plumbing and pollutes septic or sewage systems.
- Do not walk around if your shoes may be contaminated.
- Children should not help with cleanup.
Size matters too. The example institutional kit is meant for thermometer-sized spills, and that institution directs larger spills to its research safety office. In a lab, a spill larger than the kit is meant for goes to your environmental health and safety (EHS) office, not into the kit.
What varies by facility type
Requirements differ between a household cleanup, a research laboratory, a hospital or clinic, and a school. Check your own facility’s spill procedure and your EHS office for what applies in your setting.
Storage, expiry and restocking
Follow the storage, expiry and single-use statements in the instructions for use packed with the kit, and confirm the items in the table above are present when you inspect it.
Waste and rules that apply
The EPA page directs that the sealed bags be labeled as the local health or fire department directs, with cleanup materials, gloves and beads placed in a trash bag outside in a secured area. It tells the reader to contact the local health department, municipal waste authority or fire department for disposal rules. For related waste background, see RCRA hazardous waste codes, mercury thermometer disposal and particularly hazardous substances in the lab. For storing chemicals generally, see chemical storage segregation rules.
Other spill kit types
Chemotherapy, cytotoxic and hazardous drug spill kits
Kits for chemotherapy, cytotoxic and hazardous drugs are a different family from a mercury kit. They are covered in chemo spill kits.
Chemical and formaldehyde spill kits
General chemical spill kits, including what a lab typically stocks, are covered in chemical spill kits. A mercury kit is specific to elemental mercury; do not assume a general chemical kit or another single-chemical kit handles it.
FAQ
What is in a mercury spill kit?
Contents vary by kit. One institutional example lists mercury-absorbing powder, an absorbing sponge, shoe covers, a plastic waste bag, instructions and a mercury-free thermometer. The EPA improvised list instead uses cardboard or a squeegee, an eyedropper, tape or shaving cream with a brush, gloves, paper towels, bags and optional powdered sulfur.
What size of spill does a mercury spill kit cover?
The example institutional kit is for small spills, typically the size of a broken thermometer, with larger spills referred to the research safety office. Check the instructions for use for your own kit.
Can I use a vacuum cleaner or a broom on a mercury spill?
No. EPA says never to use a vacuum cleaner, which puts mercury into the air, and not to use a broom, which breaks the mercury into smaller droplets.
Can mercury go down the drain?
No. EPA says never pour mercury down a drain because it lodges in plumbing and pollutes septic or sewage systems.
How do I dispose of the cleanup waste?
EPA says to seal materials in labeled bags as the local health or fire department directs, and to contact the local health department, municipal waste authority or fire department for disposal rules.
Sources
- U.S. Environmental Protection Agency, "What to Do if a Mercury Thermometer Breaks," https://www.epa.gov/mercury/what-do-if-mercury-thermometer-breaks, checked 2026-11-04.
- Northwestern University Research Safety, "Mercury Spill Kit," https://researchsafety.northwestern.edu/catalog/mercury-spill-kit.html, checked 2026-11-04 (one institution's kit, cited as an example).
