Разоблачение: о поджигании бензина сигаретой

[jayrandom]

Разоблачение совершенно необходимо. Без этого ваши блестящие номера
оставят тягостное впечатление. Зрительская масса требует объяснения.
-- Булгаков, M&M

Lighting puddles of gasoline with cigarettes in movies is a common device. The character takes a few puffs and tosses the glowing cigarette in the puddle. Immediately, the gasoline ignites. However, numerous readers have written us saying it isn't so. Some cited experiences where they saw it attempted. Others said that cigarettes don't get hot enough.

We searched the web and found several sites that say the glowing tip of a lit cigarette is well above the autoignition temperature of gasoline. Normally this information would have convinced us, but as mentioned before, some of the people writing in seemed to have personal experience. Finally, we decided to conduct an experiment.

We poured a very small amount of gasoline in an aluminum pie pan or slightly deeper cake pan and placed it in the middle of a concrete slab. The pie and cake pans were chosen because they allowed the gasoline to spread out into a very shallow puddle the way it would if spilled on the ground. It also pretty much guaranteed that the vapors at some point above the pan would mix enough with air to form an ignitable mixture.

We lit a cigarette and tossed it into the pan. The cigarette paper wicked up gasoline and quenched the glowing tip without igniting anything (see Figure 4). We tossed in more lit cigarettes. We tried lighting gasoline soaked paper towels. We used long tongs for reaching far away objects to hold glowing cigarettes over the pan at various heights. More than once we placed several glowing cigarettes in the pan (see Figure 5). Our record was 40 glowing cigarettes at one time. In most cases, we allowed the glowing cigarettes to smolder until they went out.

Various experiments were conducted at different times of the day with different air temperatures and humidity. A total of 223 cigarettes of 11 different types were eventually used all without ever igniting the gasoline. Yet, at the end of each experimental session the gasoline was successfully lit using a single match attached to a long pole (see figures 6 and 7). The gasoline would typically ignite just before the match touched it. This indicated that there was an ignitable mixture above the surface of the gasoline. Numerous lit cigarettes were in this region for significant periods of time.

We knew that puffing a cigarette would increase the tip's temperature substantially and would help mix vapor and air together. We became convinced that puffing a cigarette over the gasoline would cause it to ignite. To test it, we built a simple smoking apparatus which could draw air through the cigarette or push it backwards out the tip.

We tested the apparatus repeatedly in both modes without getting ignition. During a test a cigarette was consumed rapidly and glowed brightly. Often sparks shot or fell off the cigarette. They were smoked at various levels above the gasoline to insure that at least part of the time they were in a region with an ignitable mixture. Surprisingly, even when a cigarette was puffed it didn't ignite the gasoline.

As mentioned earlier, we stand firm that under the right circumstances cigarettes can ignite gasoline, however, tossing a lit cigarette into a puddle of gasoline, as is done in many movies, is not a reliable way to do it.

-- отсюда.

Этот же источник исследует вероятность взорвать автомобиль, выстрелив по бензобаку из пистолета. С похожими результатами.

Comments

[wizzard]

это волшебно.

[emelja.livejournal.com]

а нам недавно на работе в рамках занятий по противопожарной безопасности показывали любительский ролик снятый где-то в германии (за кадром слышна немецкая речь). там был посередине поля сложен костер шалашиком, метров 5 высотой, как у нас на яаанипяев. какая-то компания гуляла. на земле закуски, напитки, мангалы. снималось на любительскую камеру. один мужчина из 5-литровой канистры поливал "шалашик" бензином. потом налил на землю "дорожку" уходящую от костра метров на 10, чиркнул спичкой - вспышка, изображение летит и заканчивается панорамой на уровне травы. т.е. пары 5 литров бензина разлитого посреди чистого поля на расстоянии 10 метров уже взрывоопасны. а в фильмах показывают как в закрытом доме разливают несколько 20-литровых канистр и поджигают "дорожку" в том же закрытом помещении :)

[chip33.livejournal.com]

Надо диэтиловым эфиром заправлять автомобиль, тогда все получится. ;)

[golger-i.livejournal.com]

Мне этот пост вчера очень помог.
Я вчера варил смесь воска и канифоли. Туда еще надо добавлять чуть-чуть масла. Из подходящего у меня было только baby oil, а в него добавлена какая-то парфюмерия. Я решил попробовать эту парфюмерию выпарить - налил в обрезанную сверху банку из-под пива и разогрел над плитой. И поскольку Ваш пост мне запал в память, я всё время был наготове: а не полыхнёт ли оно. Поэтому держал аккуратно и был ко всему готов.
Начало серьёзно дымить - парфюмерия, видимо, кипела. Потом дым ослаб, закипело само масло. Я решил, что хватит, выключил огонь... - и вот тут-то оно и полыхнуло. Но поскольку я был готов, ничего не запалил и не разлил.