Preparation date:
SAFE WORK PROCEDURES
MERCURY SPILLS
May 2011
Prepared by:
Dale Versfelt, OH&S
Manager
What is mercury?
Mercury is a heavy, dense metal that is liquid at room temperature. Mercury is found in a variety of electrical devices
and other equipment, including thermometers and fluorescent lights, including compact fluorescent lights (CFLs).
Mercury spills can occur at any time from fluorescent lamps, thermometers and other equipment. Significant spills
usually occur when lab thermometers or other lab equipment is mishandled or broken. If a spill is not cleaned up
promptly and properly, the mercury can be spread throughout a work area requiring a shutdown while cleanup and
decontamination takes place.
What happens if I am exposed to mercury metal?
Liquid mercury can affect human health through skin contact, ingestion, and by breathing the vapour - most worker
exposure is through the inhalation of mercury vapour. Chronic (long-term) exposure to high concentrations of mercury
vapour affects the central nervous system and can cause stupor, tremors, nervousness, and personality changes;
eventually, the kidneys become damaged.
How can I prevent mercury exposure?
The most effective way to prevent the exposure of staff and students to an accidental spill of mercury is to dispose of
all mercury-containing lab devices and replace them with mercury-free equipment. To the largest extent this
replacement of mercury equipment has already occurred in the district but there is a potential that some
thermometers and experimental mercury is still present in the secondary schools, In addition, we have potential for
spills from fluorescent lighting equipment. Fluorescent lighting tubes in Gym areas must be protected from damage.
What do I do if a spill occurs?
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SPILLS GREATER THAN 10 Milliliters - Any spills estimated greater than 10 milliliters (about the volume of a bottle
of eye drops) should be immediately reported to SD 68’s Manager of Occupational Health and Safety (250-244-2776
/ 250-713-7762) who, in turn, will contact WorkSafeBC (1-888-621-7233 during normal hours, or 1-866-922-4357
after hours) to ensure that the mercury has been properly cleaned up. WorkSafeBC staff will collect the information
and forward it to the Occupational Hygiene Officer (OHO) for our area. The WorkSafe Officer can provide additional
guidance regarding proper cleanup procedures and documentation. A hazardous materials contractor should be
retained if the spill is larger than 10 milliliters, on a porous surface, in cracks or crevices, or on carpeting or upholstery
that cannot be discarded.
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For all spills - Isolate the affected area and remove all students and personnel from the room. Open the
windows, if available, close the door(s) and prohibit entry to anyone other than District Safety or Operations
personnel. Immediately contact District Safety and District Operations to report the spill and arrange for
cleanup.
SPILLS LESS THAN 10 Milliliters - If the spill from lab equipment is small (less than 10 milliliters), and on a nonporous surface, Operations Personnel will clean up the spill using the following procedures:
Supplies you will need (contents of “grab and go” kit)
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Disposable gloves (rubber, plastic, etc.)
Eye goggles or safety glasses
Clothing that can be discarded, or disposable coveralls
Disposable booties to pull over footwear
Flashlight
Large plastic trash bags
Sealable plastic bags (e.g., zip-lock)
Plastic sheeting
Paper towels
Rags
Duct tape or packing tape
Barrier tape (caution yellow)
Plastic dustpan
Eyedropper
Sheets of letter-sized stiff paper or cardboard
Containers (glass, metal, or plastic) with tight-fitting lids
Commercially available mercury spill kit (optional)
Laminated copy of Safe Work Procedures – Mercury Spills
Spill Cleanup Steps
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Evacuate the room and block off access - close the door, and put up a warning sign indicating the presence
of spilled mercury. Use caution tape and plastic sheeting to barricade open areas. Provide fresh air by
opening and exterior windows. Shut off the room's ventilation system to avoid the spread of mercury vapour
to the rest of the building. Turn down the thermostat to slow the release of mercury vapour into the air.
2. Discard any clothing contaminated with mercury. Place contaminated items into a doubled plastic bag f\or
proper disposal. Wash affected skin immediately with soap and water.
3. Don personal protective equipment including clothing, gloves, and eyewear. Try to avoid stepping on any
contaminated surfaces. Use respiratory protection if the spill is old (i.e., it has been present for more than a
few days) and in an enclosed room.
4. Stop the spill from spreading by blocking the mercury with rags.
5. Carefully pick up any broken glass. Place the glass in a container with a tight-fitting lid.
6. Use paper or cardboard to move the droplets of mercury into a plastic dustpan. Avoid pushing the mercury
into any cracks or crevices. A flashlight will help illuminate any small droplets. Use an eyedropper or sticky
tape to pick them up. Carefully put the mercury into a container and seal the lid.
7. If the mercury has spilled on any small, porous items (e.g., clothing or a small rug), these items should be
put in doubled plastic bags for disposal. If mercury has spilled on a carpet, the affected section can be cut
out and placed in doubled plastic bags; however, it might be easier to replace the carpet.
8. Put all of the mercury-contaminated waste (clothing, rags, paper, gloves, containers used for glass and
mercury, etc.) into doubled plastic bags. Label the bags Elemental Mercury: Hazardous Waste.
9. Disposal of materials from cleanups of mercury spills will be coordinated by Occupational Health & Safety.
10. After the spill has been cleaned up, continue to ventilate the room with fresh air for at least two days before
re-occupancy.
Depending on the volume of the spill, the Safety manager’s satisfaction with the thoroughness of the clean-up, and
the intended use of the room where the spill occurred, an air quality contractor should be considered to test the
contaminated room and any adjacent areas after the clean-up.
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When a fluorescent bulb is broken, about 20 percent of the mercury in it vaporizes immediately, and it is this mercury
vapor that is the greatest health concern. If you break three or more fluorescent bulbs, keep people out of the room.
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Broken fluorescent bulbs
Open the windows and exterior doors to vent the mercury vapor to the outside for about 15 minutes before you start
cleanup of the broken lamps. If more than three fluorescent lights or another mercury containing device, such as a
Chemistry department thermometer, is broken or if you are unsure what to do, call Occupational Health & Safety at
(250) 741-5215, or (250)244-2776 at any time during the work day or (250) 713-7762 at night. OH&S will advise you
on cleanup.
Otherwise, follow these steps to clean up to three broken fluorescent lights only if they were energized immediately
before breakage. If lamps were not energized immediately prior to breakage there is a likelihood of more liquid
mercury being present which, if visible, will require a separate cleanup as noted on page 2..
After you have ventilated the room:
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Wearing disposable rubber or plastic gloves (if available), carefully scoop up the glass shards and
as much powder as possible with one or two pieces of stiff paper or cardboard. Do not use your
hands; the shards are sharp and the powder contains mercury in addition to phosphors.
Wipe the area with a damp paper towel or a disposable wet wipe to pick up any very small shards
and the powder residue. Sticky tape, such as duct tape, can also be used to pick up small shards
and the powder. Do not use a vacuum until you have cleaned up all the visible powder and shards.
Place all the glass shards, powder, and materials you used in the cleanup (gloves, paper, towel,
wet wipe, and tape) in a plastic bag that can be sealed.
Then place this sealed bag inside another bag and seal it. Keep this in a safe outdoor storage
location until and while you take it back to SD68’s Hazardous Material Waste storage facility
(contact Safety Officer 250-741-5215). Do not carry the waste materials inside an enclosed
vehicle.
Wash your hands.
Now you can vacuum. Ventilate the room during and after you vacuum. When you are done, put
the vacuum bag or the contents of the canister in double-sealed plastic bags.
Place this bag in the trash outdoors until normal disposal.
If a fluorescent light breaks on a carpeted surface, follow the cleanup procedure above, using gloved
hands and sticky tape to pick up as many shards and as much powder as possible. If there is visible mercury liquid it
must be cleaned up following the directions on page 2 before you vacuum cleanup.
DO NOT
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Use a vacuum cleaner to clean up liquid mercury. The mercury will pass through the vacuum and
contaminate the air (as well as the vacuum cleaner).
Use a broom or brush to sweep up mercury. This will break up the mercury into even smaller droplets and
spread them around.
Wash mercury-contaminated items in a washing machine. You will contaminate your washing machine and
may pollute the sewage system.
Pour mercury down the drain or put contaminated items into ordinary garbage.
Mercury spill kits
A mercury spill cleanup kit is availablefrom District 68’s Health & Safety Officer. The kit contains:
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A neutralizer (which chemically converts mercury into a less hazardous form)
An aspirator (which is used to pick up globs of mercury)
Personal protective equipment (gloves, safety goggles)
Disposal bags
Labels and instructions
Report all Mercury Spills to Occupational Health & Safety and Operations
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The neutralizer is sprayed on the spilled mercury and any mercury-contaminated surfaces before the spill is cleaned
up. The neutralizer can also be applied after the mercury has been removed to neutralize any residue.