Your average graveyard or mausoleum worker would, under normal circumstances, expect to find everything back in its place between shifts. In fact, I have a hunch that people who work at cemeteries aren't very fond of surprises, especially when they involve exploding corpses.

And yet, every now and then there are news reports of just this happening. There is no data on how frequently this occurs, but it affects the subset of bodies that are placed in caskets above ground in mausoleums.

Is this a feature or a bug? Is there a way to stop it from happening? Are there other funeral practices we need to watch out for? In order to find out I spoke with Josh Slocum, executive director of the Funeral Consumers Alliance, a nonprofit watchdog organization that bills itself as the equivalent of Consumer Reports for funeral services.

Tell us why corpses are exploding.

Take leftovers in your refrigerator. Everybody knows what happens when you put a piece of meat in Tupperware and you let it sit for a long time. Takes a little longer in the fridge because it's cold, but if you leave it to sit out, I'm sure many of us can remember some time when we pop open this Tupperware and cringe when this nasty smell comes out. Human beings are meat just like all other animals are meat. When you seal up a body in an environment that locks up heat and humidity, anaerobic bacteria take over. You're gonna rot regardless, it doesn't matter if you're sealed or not. But the problem is how unpleasant the consequences can be when you seal it up and you deprive the body of air circulation and dehydration.

How unpleasant?

Basically, the casket becomes a literal pressure cooker. It reduces the body to a disgusting chunky brown slurry. It's horrendous. I have not seen this in person with my own eyes, but I have seen many photographs of families who called in with complaints and lawsuits that I've consulted on. Imagine a casket coming out of the mausoleum with what looks to be gallons of thick brown muck flowing down the front of the mausoleum and onto the sidewalk, [then] opening up that casket, and seeing little inside but wet fabric and a vague human shaped stain. Nasty.

How does the explosion happen?

We know that decomposing remains of any sort produce gas. That's composting, that's the smell of road kill. This is just the normal decomposition process. When you bottle that up so that it can't get out. I think there certainly have been cases where the pressure was sufficient to blow that little square front off the front of the crypt. I think mainly, more commonly rather than a "boom" explosion you get the lid popping and then fluid and gas coming out or running out. It's disgusting, but know this right up front: it is not disease-bearing.

I guess that's a small consolation for the people that work at mausoleums?

Yeah. But I often visit cemeteries, [and] I can tell you instantly when I go to a mausoleum whether that place is properly vented.

Is there an actual reason to seal caskets?

Don't ask for logic or rationality here. What you've got is a crazy system where the funeral industry is trapped by a mythology of its own making, and it can't come clean about it to the public.

What are you supposed to do instead?

Reasonable mausoleum owners know that you want ventilation, and not to have things sealed up. This is why you see the occasional lawsuit where a cemetery operator has surreptitiously gone into the mausoleum and propped casket lids open a couple of inches to facilitate dehydration. That's because they know what happens.

Why is that lawsuit-worthy?

They went in there and did that after the family bought this sealed casket that was labeled "protective" by the funeral home. The whole thing conspires in this strange way. A well-designed mausoleum will have the crypts themselves inclined very slightly to the rear, to a drainage pipe so that fluids that come out will be drained away discreetly. And it will be designed in such a way so that fresh air exchange is constantly coming through the crypts themselves facilitating dehydration out of a discreet vent in the back of the building.

Good mausoleum architecture prevents explosions?

Some aren't designed very well, and in still other cases depending on how tightly the casket is sealed or screwed down, you may have problems anyway.

Will a sealed casket always have this problem?

Likely, but not always. The largest manufacturer of caskets claims that its caskets "burp." They're meant to allow excessive gas to burp out of the casket so that pressure doesn't build up. And I'm sure that that works sometimes. But sometimes it doesn't.

How can someone who wants a mausoleum burial avoid all this?

Big cemeteries owned by big corporations are likely to have these shoddily constructed mausoleums and make all sorts of promises about them that may not be true. But it's not confined to corporate behavior. If you actually want a clean and dry mausoleum burial, your best bet is to be in a plain Jane simple coffin that does not seal, that can allow air circulation, and in a well-designed mausoleum.

Has this always been a problem with mausoleums?

I was in Baltimore a couple of months ago and went to a famous historic cemetery. There were a lot of above ground mausoleums. Old school ones, these were nineteenth century burials and they were made out of brick. They were one story high, they weren't buildings. They were just mounds outside that you just had to kneel down to see the inscription. And in the cast-iron doors there were large holes, which I assume were for ventilation. I looked in there, used my flashlight to see what I could see, and you'd see what you'd expect: old pieces of wood coffin broken down, some bones, very dry. It's what people think of when they think "old skeletons found in the cave" or something. They'd just put folks in there in a cloth, or shroud, or in a coffin and let nature take its course. This is very different from what you see in a modern mausoleum.

What should people keep in mind if they don't want their loved one to become an exploding corpse?

Nothing that happens to dead bodies is pretty. There is not a damn thing you can do that's pretty. Decomposition in the ground is gross. Decomposition into a slurry is gross. People probably wouldn't want to watch the actual process of burning someone at 1600 degrees that takes place during cremation. Anatomical dissection is also gross. This is just life. So if you find yourself having emotional twinges about the condition of the body, I strongly urge you to step back. Stop for a minute, and remind yourself: Whatever happens to the body is not going to be aesthetically pleasing, but it's something you can't control very much.

What are the sales pitches people should look out for?

You can't stave it off, and if anybody's trying to sell you something that they call "preservative" or "protective" you should immediately stop the conversation. You are being lied to and you are being taken advantage of. If you were in an ordinary frame of mind, does this make sense to you? That you could "protect" your husband's body from something? Most people would say, "No, that does not make sense to me," when they are not in the throes of grief.

Why do you think people aren't making informed purchases?

The biggest problem—aside from the fear—is that most everything that people think they know about funerals is wrong. We have mortuary mythology that we carry around in our heads, that unsurprisingly works out to the favor of the undertaker's pocketbook. Many people believe, for example, that embalming is routinely required by law. False. Most people believe that coffins in vaults are required by law during burial. False. People think that sealed caskets can preserve a body. False.

How did these myths proliferate?

Mortuary schools around the country were started by the embalming chemical companies 130 years ago. There is an entire century of culture in which the mortuary school students have been indoctrinated into a false idea. It's not a matter of opinion, it's scientific nonsense. The idea that embalming disinfects the body and protects public health is utter bullshit, but they believe it. The only health related issue that comes from embalming is from exposing the embalmer herself to formaldehyde and to bodily fluids in great quantity that would not be there if they weren't mucking about opening up the corpse.

Americans are also weird about seeing bodies, right, exploded or otherwise?

We've all grown up in this culture with this set of ideas too, that to see the body embalmed and with lip coloring and all this sort of stuff and it shocks the hell out of people to hear that most of the rest of the world doesn't do it. And it shocks funeral homes to consider showing unembalmed bodies. I've seen disclaimer forms that they make people sign that say they won't be held responsible for emotional distress and all sorts of bullshit.

Speaking of American peculiarity, one thing that I was surprised to find out is that in Greece where I grew up (and presumably elsewhere), "mortician" is not a certified profession. It's just handed-down knowledge. Do you think the US approach even serves a purpose?

Burn it to the ground. The licensure and legal restriction of undertaking to a certain guild has been an absolute disaster that has done nothing for consumers but drain their wallets. It's horrendous. I would far sooner see a system like what you describe. The only thing funeral directors in this country can do that we can't is embalming. Mortuary school is a two year degree. Nine months of that two years is spent on embalming which is extraordinarily excessive considering our cremation rate. The rest of it you get a smattering of marketing caskets, small business administration, and some very very poor psychology.

So do you agree that it's the living we should be concerned about, because even a sludge-corpse is just gone?

You cannot do anything for your dead grandmother. You can't insult her. You can't canonize her. You can't get her into heaven faster. You can't do anything to her or for her because she is gone. What you can do is something that is meaningful and appropriate to you, your family, and everybody else. [...]The first thing to do is to stop apologizing to yourself and to the rest of the world for treating this transaction for the business transaction that it is.