John Maher: Hi, I’m John Maher. I’m here today with Robert Weitz of RTK Environmental, an environmental testing and consulting firm.
Robert is an EPA certified lead paint inspector and risk assessor, as well as an abatement planner and project manager. Today, we’ll be talking about lead dust.
Welcome, Robert.
Robert Weitz: Thank you.
How is lead dust created in a home?
John: Robert, how is lead dust created in a home?
Robert: Lead dust is created in a home in a couple of different ways, actually.
It can be caused by normal deterioration of lead paint; through wear and tear, or just on an exterior of a home. Particularly weather and the elements help to deteriorate paint over a period of time.
I’m sure that most people who have a painted house outside know that you have to repaint it every four or five, six years. That’s because the paint deteriorates. That’s certainly one way that lead paint turns into lead dust, which is the primary cause of poisoning.
Then also, lead painted surfaces can be intentionally disturbed. We can go back to the outside and say when you repaint that house and the painting contractor comes in, and they have these disc sanders, and they start sanding the paint down in order to make it smooth again before they paint it.
That’s certainly generating a tremendous volume of lead dust. We’ve done a lot of inspections where children have been poisoned, unfortunately, because the parents didn’t know. They just didn’t know the painting contractor wasn’t knowledgeable about the hazards of what lead dust does.
Those are the two main ways that lead dust is generated, by normal wear and tear, and deterioration of paint, and then also by disturbing it.
Lead Paint in Homes
John: If you know that you have paint on the outside of your house and you do need to get it repainted and sanded, like you said, are there things that a painting company can do to keep that dust down to a minimum?
Robert: I think the first step in that process, naturally, is to have a company like RTK come out and do a professional lead inspection. We need to know definitively from the start are we dealing with lead paint or are we not dealing with it.
Any home built before 1978 potentially has lead paint. By doing a simple XRF inspection is what it’s called. By doing a simple inspection it takes a short period of time. Now, we can identify, this has lead. This does not.
The contractor at that point is required now by federal law to have at least some training on how to deal with a surface like that. Basically, it involves wetting the surface, and then scraping or sanding so that dust is not generated.
They would have plastic sheeting down on the ground around the house, all the material that’s falling from their work would fall down wet onto the plastic.
Then, when they’re done with a particular area or at the end of the day they would take that plastic and they would roll it into itself so that none of that material would be able to get down onto the ground.
Lead Dust and Lead Poisoning
John: Why does lead dust post such a risk to people? You said that it is the most common way that people get lead poisoning.
Robert: Yes. It’s the number one cause of lead poisoning. Many people think incorrectly that lead poisoning most often occurs by the child sitting on a floor next to a window that’s peeling and picking up the paint chips and eating them.
Yes, that does certainly happen. It happens a lot, but the primary cause of poisoning, particularly in children, is the dust itself.
John: I think that that’s really a danger since it’s just dust you can’t tell the difference between lead dust and plain old regular dust that you find in your home all of the time. You have no idea that this is happening.
Robert: Exactly, particularly if you haven’t had a lead paint inspection done to know if there are any lead painted surfaces. Then, you have less information.
Education is really the key here. One of the things that we do mostly at our company, we don’t sell inspections really. What we do is we educate our client, and then through that education, they’re able to make a decision of, “This is something that’s really very important for me to do.”
For almost all people, doing a lead paint inspection is a no‑brainer. It’s a very important inspection to have done for almost all people.
How to Prevent Lead Dust
John: Can homeowners help to prevent lead dust from forming?
Robert: Absolutely. Once they know whether the lead is there or not, then they can take several precautions. That’s part of our education process.
They want to make sure that the lead painted surfaces stay in an intact paint condition. Lead paint sitting on a wall or a sitting on a piece of trim or a baseboard is not a hazard as long as it stays in good paint condition.
It’s when it begins to deteriorate. As soon as we’ve identified lead paint, many people put together what’s called a management plan. A management plan is a document that would indicate where the components are that tested positive for lead.
And then on a periodic basis, usually every six months or so, to do a deliberate visual inspection, and go room by room and say, “OK, this windowsill has lead. It’s still in good condition. We’re OK.” We check it off the list.
“But wow, we went into the kitchen where we know the walls have lead paint and Johnny’s ridden his bicycle into the wall there,” or whatever the case might be. Then that component has become defective. That’s when it becomes very much potential for a lead ingestion, and then subsequently a lead poisoning.
How does a lead inspection detect lead dust?
John: How does a lead inspection detect lead dust?
Robert: The lead inspection is done with an x‑ray device that’s called X‑Ray Florescence. The acronym is XRF, in simple terms.
What this device does, it’s a great device. It’s handheld. It’s very small. It looks like a police radar gun.
We hold that up to a number of different surfaces in each room, usually 10 to 20 different components. By just pulling a trigger, it reads the paint layers all the way down to whatever the substrate is; wood, or sheetrock, or plaster.
We’re getting a full picture of every paint layer, and where the lead paint is if it’s there. Either if it’s deeply buried, which is very often the case, because lead paint was banned in 1978, or if it’s closer to the surface where it could potentially, even in good condition, be more of a hazard in the environment, particularly to a child where lead poisoning is most prevalent.
John: Using this method, a homeowner would know very quickly whether or not they have lead paint or lead dust in their home, because you don’t even have to send samples out to a laboratory or something like that.
Robert: Lead paint, that inspection, the XRF inspection is specifically for lead paint. The dust is tested in a different way.
The lead is picked up in a dust wipe sample. What we do typically, is if we identify lead paint, particularly in the XRF inspection, then we know that it’s potential for lead to be in the dust.
We take a dust wipe material, which looks like a baby wipe, and we wipe a given surface that’s measured specifically. We wipe that surface. We take all of the dust off of that. We fold that up and we put it into a tube that’s called a centrifuge tube.
We send that out to a laboratory. They go through an analytical process that will tell us in micrograms per square foot. It’s very exacting, how much lead is in that sample. There are certain levels that are acceptable and unacceptable, depending upon whether we tested a floor, a windowsill, or a window well.
Those are levels that are established by the Department of Housing and Urban Development. They’re very low. Again, they have been lowered through the years. A floor, for example, many years ago would say 200 micrograms per square foot is acceptable. Anything below that is acceptable.
Now, the level for a floor is 40 micrograms per square foot. The reason for that is because more and more, the CDC particularly, is finding that the lower levels are even very bad, particularly for children, to have in the bloodstream.
John: When you come into a home to do a test, the first thing you would do would be that XRF test, so that you can find out if there’s lead paint in the home.
If you do find that there is lead paint existing in the home, then you can move on to doing the dust wipe test, and taking a sample to see whether or not there’s lead in the dust.
Robert: That’s correct. That would be a very common way for things to occur.
Sometimes, people live in a house that was built at the turn of the century and they assume that they have lead paint. Sometimes people just call us in and say, “I want to have lead dust samples taken. I want to know what I have in the dust. I believe that I have lead paint and I assume that I do. I just want to have the dust wipe samples taken.”
Whatever someone wants, as long as we educate them, and let them know the value of doing the lead paint inspection, even though they assume they have lead paint.
Lead paint is rarely on every surface. Usually on the interior of a house especially, it might be on the trim-work, windowsills, doors, door casings, baseboards, crown molding, because more durability was required on those surfaces than walls or ceilings, for example.
Very often even in an older home we may not find any lead paint at all on the walls or ceilings. But we may find very high levels on different pieces of trim. It’s important to know from that XRF data, “What are we working with here? What’s high? What’s low? What’s the biggest risk for a child or even for an adult?” And to take precautions based upon those readings.
John: Robert Weitz, thanks very much for speaking with me today.
Robert: You’re welcome. Thank you for having me.
John: For more information, you can visit the RTK website at rtkenvironmental.com or call 1‑800‑392‑6468.
