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Marian Perera
06-14-2010, 02:00 PM
Hi everyone, hope you can answer a question I have.

Let's assume that you're in the center of a circle of dry grass. The circle has a fifteen-foot radius, and its entire area has been soaked with highly flammable oil. Someone sets it alight.

Your clothes are soaked, thanks to your falling in a pool of water beforehand, but you have no other protective equipment at all. Assuming you were running, is it likely that you'd be able to reach the outside of the circle without serious injury?

And if this would be too easy, I may need to increase the circle's size a bit.

Thanks in advance!

alleycat
06-14-2010, 02:07 PM
Is this like dry lawn grass, or tall grass?

In any event, I don't think it would be that hard to escape without injury given your conditions.

Marian Perera
06-14-2010, 02:34 PM
Is this like dry lawn grass, or tall grass?

It's in a cemetary, so I'm going to say the grass is kept relatively short.


In any event, I don't think it would be that hard to escape without injury given your conditions.

Crud.

Guess I need more oil.

KTC
06-14-2010, 02:41 PM
It wouldn't burn for a long time...there's not enough to keep it going. I think basically the oil would burn off and you'd be left with black charred dead grass. I could be wrong. I know I once saw a field burn up...granted there was no oil on it...and it went up like paper, but the fire moved...it burned so fast that five feet away would already be out as the 'head' of the fire moved through the fresh grass. I think if you were to run through it, you'd be fine...you'd find a place where the fire already passed through pretty quickly. I could be wrong...maybe someone else who knows better will come along. (-;

leahzero
06-14-2010, 02:46 PM
If you need it to be more dangerous, and it's taking place in a cemetery, you could have it be in an unkempt area with lots of dry underbrush, flinders of wood, etc. Maybe even some kind of wooden monument or structure (toolshed, etc.) nearby to use as fuel.

Marian Perera
06-14-2010, 02:46 PM
Well, dang. I really wanted to make this tough for my protagonist.

On the other hand, he's carrying a semiconscious person who was left in the center of the circle to draw him into it. Maybe that'll help.

ETA : That idea has potential, Leah. This all takes place at the base of a famous person's headstone, so it's not an unkempt area. But people might have planted flowers or small shrubs there and those could now be dry, making perfect kindling.

DrZoidberg
06-14-2010, 02:51 PM
There could be lots of smoke (green grass) and you could perhaps have stuff on the ground your MC can trip over?

Marian Perera
06-14-2010, 03:19 PM
The more I think about this, the more I want him to do something smart. Running out while trying to carry another person may be dramatic and heroic, but it's not startling and clever.

Maybe I need to think about it some more. He certainly doesn't have any way to put the fire out. I wonder if the headstone's construction would help at all.

jclarkdawe
06-14-2010, 04:51 PM
Short of magic or gross stupidity, I think you have problems.

First problem is I'm not sure you'd generate enough BTUs with even tall grass, unless you're burning quite a bit of area. Unless you stand in the fire, it's probably not going to generate enough heat to damage a human body. Frequently at brush fires you can step right over the fire to shift position.

Second is the wait and see approach. You're not going to have a fuel source that's going to last very long. Wait five minutes and the fire is going to die down a lot.

I don't want to minimize the danger of a brush fire, but under normal conditions, they aren't very bad. The danger in a brush fire usually involves a combination of slopes and high winds. The videos you see on the news are all wind-driven flames, whether from regular winds or winds generated by the updraft. I'm talking winds in the twenty plus miles an hour range.

The protective gear for a brush or forest fire usually consists of a Nomex shirt, maybe Nomex pants but more often a pair of jeans, and boots. Helmet is to protect from falling limbs. My preference on gloves was leather, but a lot of people figure out their own. Although some people use the gloves they use for structure fires, usually they are a lot lighter.

Getting a brush fire to dangerous levels is unusual. That's why they make the news. Most of them are very boring.

Best of luck,

Jim Clark-Dawe

Marian Perera
06-15-2010, 01:39 AM
Short of magic or gross stupidity, I think you have problems.

...

Second is the wait and see approach. You're not going to have a fuel source that's going to last very long. Wait five minutes and the fire is going to die down a lot.

Thanks for the information, Jim. There is a lot of magic used in the story, so the protagonist is concerned about this. The twist is that because everyone expects to see magic, and takes precautions against that, someone who uses more mundane methods to attack people is getting away with it.

But I'd like it if the protagonist was aware of what you said, that a fire caused by oil and dry vegetation is going to die down quickly. I'm thinking he manages to find a foothold on the (very elaborate) headstone, enough to be out of reach of the flames.

Then the entire thing tips over and drops him back in it.

And that's due to magic.

jclarkdawe
06-15-2010, 02:08 AM
But I'd like it if the protagonist was aware of what you said, that a fire caused by oil and dry vegetation is going to die down quickly. I'm thinking he manages to find a foothold on the (very elaborate) headstone, enough to be out of reach of the flames.

Smart people know that smoke and heat rises. That's why firefighters spend so much of their lives crawling.

Dumb people figure it out real quickly, as they get hot and start choking.

Have him go in a ditch, or better yet, where a new grave settled a bit, creating a hollow in the ground. Then have the gravestone fall, which could be either magic or the ground settling. Leave people to wonder for a bit.

Best of luck,

Jim Clark-Dawe

Hallen
06-15-2010, 03:26 AM
It totally depends on how long he stays in there and how high the flames are. Assuming the fire completely engulfs the 15 foot circle in a half second and the flames are intense and tall enough to be over his head and he has to pick up the other person and run out: He is going to get severe 3rd degree burns on any exposed skin, and if he takes a breath, his lungs are going to take very bad, if not deadly, damage. It will only take him a second or a bit more to go the 7.5 feet out of the circle, but that's long enough.

Even a second in flames will give you bad burns. Hold your finger in a candle flame for a second if you don't believe me.

The wet clothes will help a lot especially if they are layered cotton and wool and they are soaking wet. They won't catch fire and they will insulate from most of the heat. Any place where the clothes are very tight, backside of your pants, thighs, etc, you'll probably still pick up burns there, but not as quickly as bare skin.

But why would he be in a circle of flammable liquid knowingly? It'll be pretty obvious from the smell.

The height of the flames would be key. If they stay close to the ground, within a foot or two, he'll probably be able to walk out with no problem. If the flames are tall and intense, then he's going to get badly burned unless he wraps all exposed skin in wet clothing.

My take on this comes from military training and aviation safety. Fire is obviously a critical concern in aviation.

Marian Perera
06-15-2010, 03:28 AM
What if the gravestone tipped over, creating the hollow in the ground, and he dropped down into the hollow where the coolness of the earth and the lower elevation would help?

I think I can actually make that work, which is a relief. I've been fretting over this scene all day.

Tsu Dho Nimh
06-15-2010, 03:49 AM
His main danger would be inhaling hot gases and burning his lungs and the victim's lungs.

Hallen
06-15-2010, 04:17 AM
What if the gravestone tipped over, creating the hollow in the ground, and he dropped down into the hollow where the coolness of the earth and the lower elevation would help?

I think I can actually make that work, which is a relief. I've been fretting over this scene all day.

That could work especially if he had something to pull over the top of them. (Think of the special fire blankets that wildfire fighters have in their emergency packs) Like said above, breathing the hot gasses can be deadly so using some of his wet clothing as a filter/cooler might help for a very short while. Holding his breath, not allowing the victim to breathe would be the best thing.

LoopyLinde
06-16-2010, 05:45 AM
I've been in cemeterys with lots of trees. Is there a reason it has to be only grass that burns?

jclarkdawe
06-17-2010, 12:48 AM
What if the gravestone tipped over, creating the hollow in the ground, and he dropped down into the hollow where the coolness of the earth and the lower elevation would help?

I think I can actually make that work, which is a relief. I've been fretting over this scene all day.

I'm sorry, I meant to get back to you sooner on this.

Modern gravestones are frequently set in concrete, but that isn't well known and I think we can ignore it. A gravestone set in earth would be down into the ground about a foot or so, so if it tipped over, as opposed to breaking off, it would dig up about a foot of ground. (The old, thin gravestones tend to break off at ground level, so use one that is a few inches thick.) (Normally for an upright object, you try to hit the point of balance very little above ground level. For example, the Seattle Space Needle's center of balance is approximately five to ten feet above ground level. There's a whole lot of concrete below ground holding the sucker up.)

Standard training for brush fire fighting is if crap habits, to find the lowest spot possible and pull the space blanket you have with you over your body. Praying is optional, but frequently utilized. Technique requires a lot of guts but works pretty well. If you have time, removing any brush from around you improves the odds.

So if I was encircled by flames that were life threatening, and was near a tombstone that had fallen, I'd use whatever I could to expand the hole, then crawl in as much as I can and cover myself with dirt (which is a good insulator). If I had no tools with me, I'd use my heels to dig with rather than my hands.

Wet cloth over mouth would provide some cooling to the air. If no wet cloth is available, any cloth provides some filtering effect.

Realize that all you're trying to do here is increase your odds as much as you can. You have no idea what the minimum you have to do to survive.

For a singer surrounded by a circle of fire, you might want to watch Johnny and June (http://www.cmt.com/videos/heidi-newfield/255916/johnny-and-june.jhtml) by Heidi Newfields. It's about two-thirds of the way into the video if I remember right. Fire seems to be fueled by kerosene, but I can't be sure. It's not especially exciting.

Best of luck,

Jim Clark-Dawe