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Alameda County, CA, acgov.org

Larry Brooks
Director
Healthy Homes Department
Including the Lead Poisoning Prevention Program

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How to Test for Lead


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The best way to find out if there are lead hazards in your home or yard is to hire a State lead certified inspector/risk assessor. Go to our Consultant Listing* (PDF - 137kb) to find local consultants who have expressed interest in performing lead evaluations for property owners.

If you decide to collect samples yourself, be sure to follow the procedures outlined below. Most of the time, the samples that you will want to collect are either dust, paint, or soil samples.

Once you have collected the samples according to the instructions below, send the samples to an accredited laboratory. See a list of local accredited labs and prices (PDF - 249kb) .

* Portable Document Format (PDF) file requires the free Adobe Reader.

Collecting Dust Samples

WHAT you will need:

  • Clean plastic bags with a Ziploc closure
  • Unpowdered disposable latex gloves (if available)
  • Tape measure or ruler
  • Baby wipes
  • Clean hands

If you are going to take several samples, be sure to wash your hands before collecting samples and use a clean pair of disposable latex gloves for each sample.


WHERE to sample:

Areas in your home where your children normally play should be the first to be tested. The surfaces that you test should be smooth and non-porous, like linoleum, painted wood, or wood floors. Good places to test include:

  • Entryway (including porches).
  • Children's principal play area (usually the TV room or living room).
  • Children's bedrooms.
  • Kitchen.
  • Bathroom

WITHIN these rooms, places that are likely to have high dust levels are:

  • Floors near friction or impact spots (usually doors and windows)
  • Floors near areas with deteriorated paint.
  • Interior window sills (of frequently opened windows).
  • Window troughs (of frequently opened windows).

HOW to sample dust:

  1. Outline the area to be wiped with tape or a template. The preferred area is a square 12 inches by 12 inches (one square foot). For places where wipe samples are taken and are not this big (like a window sill), measure the dimensions (width and depth) for lab use. Results will be reported as micrograms per square foot (ug/ft2).
  2. Put on disposable, non-powdered, latex gloves.
  3. Remove a wipe and place it on the surface, but within the area you taped off. Wipe the area from side to side "S" motions. Fold the wipe in half by picking it up in the middle so that the just-wiped side is folded into itself leaving an unused side outward and complete a second pass going from top to bottom.
  4. Fold the wipe (contaminated side facing inward) and place it in a sealable plastic bag. If there is gross debris such as paint chips, try not to lose any material collected in the wipe.
  5. Label the bag and record information (including sampling area measurements) on a piece of paper for your own records
  6. Place a clean , unused wipe into a clean plastic bag and label the bag as a Field Blank. This will allow you to determine if there is any lead in the materials you are using to collect the samples.

HOW to Identify the Samples

Collect all the samples in Ziploc plastic bags and write where you got the sample from on the outside of the bag with a permanent marker. Write this same information onto a piece of paper for your own records so that you can match the result(s) from the laboratory with the sample(s).

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Collecting Paint Chip Samples

WHAT you will need:

  • Knife or chisel
  • Clean hard containers (jars, film canisters, etc.)
  • Unpowdered disposable latex gloves (if available)
  • Clean Hands

WHERE to Sample:

If you have paint from different areas (different colors), it's a good idea to collect them as different samples.
If you are going to take several samples, be sure to wash your hands before collecting samples and use a clean pair of disposable latex gloves for each sample.

HOW to Collect Samples:

Collect the samples in the containers and write where you got the sample from on the outside with a permanent marker. Write this same information onto a piece of paper for your own records so that you can match the result(s) from the laboratory with the sample(s).

a. From a wall, window or doorway - Use a knife to scrape sections of paint, at least the size of a quarter, down to the bare wood, plaster, stucco. etc. Don't take the wood, plaster, stucco, etc. with your sample or your results won't be accurate. Be sure to get all layers of the paint.

b. From the Ground - Open the container, pick up different sizes, thickness, etc., of paint chips with an unused plastic spoon, and place the chips into the bag. Seal the container. Throw the spoon away, remove your gloves and throw them away, and wash your hands.

HOW to Identify the Samples

Collect all the samples in containers and write where you got the sample from on the outside of the container with a permanent marker. Write this same information onto a piece of paper for your own records so that you can match the result(s) from the laboratory with the sample(s).

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Collecting Soil Samples

WHAT you will need

  • Plastic spoons
  • Clean plastic bags with a Ziploc closure
  • Unpowdered disposable latex gloves (if available)
  • Permanent marker
  • Paper and pen
  • Clean hands

Wash your hands before collecting samples. If you are going to take several samples, you should use disposable latex gloves and be sure to use a clean pair for each sample.

WHERE to sample

Areas in your yard where your children normally play should be the first to be tested. This includes sandboxes, along the building foundation or drip line, and next to the building if there is chipping, peeling, flaking or chalking paint. Soil in other areas such as near a street, may also contain lead. These areas pose less danger if your children do not spend much time in or around them.

HOW to sample

Single Spot Sample
  1. Collect the top 1/2 inch of dirt with a clean spoon, (about 1 cup of dirt) and place it into a plastic bag. Seal the bag. Throw the spoon away, remove your gloves and throw them away, and wash your hands.
Whole Yard Sample
  1. Choose five places in your yard at least two feet apart without grass or ground cover. Draw an imaginary "X" on the ground and take samples at the middle and all four corners. Collect the top 1/2 inch of dirt from each area with a clean plastic spoon, (about 1/4 cup of dirt from each of the five places) and put them into the same plastic bag. Seal the bag. Throw the spoons away, remove your gloves and throw them away, and rewash your hands.

HOW to Identify the Samples

Collect all the samples in Ziploc plastic bags and write where you got the sample from on the outside of the bag with a permanent marker. Write this same information onto a piece of paper for your own records so that you can match the result(s) from the laboratory with the sample(s).


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* Portable Document Format (PDF) file requires the free Adobe Reader.


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