Q+A: A Texas firefighter on staying safe in LA
Matt Heerwald shares tips for cleaning up and weighing health risks
CJ Mattia: Thanks for talking to me today. Would you mind telling me who you are and what you do?
Matt Heerwald: My name is Matt Heerwald, and I'm a lieutenant with the Austin Fire Department.
CJM: Can you tell me about the differences between a brush fire, wildfire, and a hazardous material fire?
MH: A brush fire is a type of wildfire—think of it as a small wildfire. A wildfire is once it’s [in] the trees, and is starting to spread more rapidly. A hazardous materials fire is exactly what it sounds like. When a hazardous material is on fire—that can be a truck that’s hauling gasoline, or it could be a garage that’s on fire—that’s going to release a whole lot of nasty stuff that we don’t want to breathe. So, if you see black smoke billowing out of a house fire, stay away from that.
CJM: How would you classify the recent fires in LA?
MH: All of the above. There are certainly brush fires, and those are not a good thing, but it’s probably not your biggest worry. Your worry is that turns into a big raging wildfire that’s difficult to control. Anytime that fire gets to a structure or a vehicle—anything synthetic—you technically have a hazardous materials fire. That’s a massive problem. It’s bad for the environment, it’s bad for the water table, it’s bad for the air.
CJM: What’s the difference between particulates and vapors? And, how do masks protect against these things (or not)?
MH: Particulates are things that can be filtered out of the air with a mask. Vapors are going to go right through an N95 mask. If I had the choice between wearing one, or not, I would, because it’s going to catch the larger particulates. By the time the dust settles and everything’s no longer smoking and smoldering, those are good for you. If you’re going to volunteer somewhere, and you're gonna be shoveling and kicking a bunch of stuff up in the air, and you have access to a higher grade mask, then I would use it.
CJM: Do you have any advice for people returning to areas near fires, or homes that have been through fires?
MH: Approach from uphill and upwind, because the wind will naturally take that stuff away from you. When your hot zone is as big as the LA area is, it becomes tricky [especially] with these sorts of unpredictable winds. You might be upwind of the stuff in front of you, but behind you, there could be some other nasty stuff blowing. But, generally, try to to stay uphill, upwind.
CJM: Is there anything specific people should wear when cleaning up, other than masks?
MH: I would say natural fabrics are better. Having a good pair of strong, sturdy, impermeable footwear would be high on the list. Rubber is best. Leather would be good, but sloshing around in your shittiest pair of Nikes all day is not on the list of things to do. This stuff can go straight through any rubber soled shoe. There's going to be nails, screws, glass, [and] sharp metal pieces everywhere.
CJM: What else do we need to look out for during cleanup?
MH: You don’t want to burn your hand, by picking up something hot. Look out for smoke. Sometimes, something is very hot, but may not actually be on fire. You might not see flames, but the atmosphere right above it gets really wavy—kind of like when you’re looking down a highway in August. Certainly, if you’re [using] water, and it sizzles, stay away from that. Avoid digging through piles that are smoldering.
Digging around, especially when you are sweaty and your pores are open, that stuff seeps into into your system. If you find yourself out there getting dirty, go home and take a shower.
CJM: What are some of the health concerns associated with this kind of event?
MH: I wouldn’t say one acute event, like a house fire, would give you cancer, but a whole lot of it for a long time will. One of my first lieutenants was at 9/11 and he died of stomach cancer three years ago. Comparing 9/11 to LA…I don’t know. But, it's a huge hot zone, and people in LA are going to be wading around in that shit for a long time. It's going to be on all of the surfaces and leeching into the the dirt.
I'm not trying to be alarmist. I wouldn't walk around without a mask. The culture of the fire service is much more safety-conscious than it used to be fifteen years ago, because so many of us have gotten cancer and died. I know we all want to help. I’m guilty of it, too. But, I don't think that the public understands the risk. They're like, “it’s just a little bit of smoke”—but you’re going to be getting enough of that crap, just by living in the area.
CJM: Do you have any thoughts about how we should think about health risks, given all of this?
MH: The way I live my life is kind of 80/20. If I go and take a shower as soon as I'm done, I've knocked 80% of the bad stuff out of my system, and it won't seep in. Now, 20% of it may make it through, but at least I'm getting the big chunks off. So, certainly shower. Don't go home, and crash out on the couch and let all that stuff seep in.
Also, is digging through all of your stuff while it’s still smoldering worth it for you? Is it worth it to you to dig through somebody else’s stuff? I’m generous, but maybe not that generous. I’m all for helping people, with the caveat that it doesn’t help anyone if we all go out there and get cancer.
With cleanup, do the best that you can. You’re not going to get it all. Your grandkids are going to be flipping through your books and going, “Oh my God, there’s still dust in here from the great fire of 2025!” But, you’ve gotten the big chunks, and that’s worth a lot.
CJM: How long is it going to take to recover from this?
MH: Decades? I don’t say that lightly. This is one of the biggest disasters to befall the United States in a long, long time. There’s going to be scars from it forever. It’s going to be a bad situation for a long time. Things will get back to normal—to a new normal—but, if your question is when will it stop being a hazmat zone? I don’t know. There’s probably just going to be some assumed level of risk living there.