0:00:00.322,0:00:02.499
When roofing with an open flame

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a gas burner is used.

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It produces long flames and

0:00:06.184,0:00:07.548
can easily start a fire

0:00:07.548,0:00:09.317
in materials nearby,

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or lead warmth

0:00:10.753,0:00:12.833
through cavities, ducts and so on.

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This is especially dangerous in older buildings

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where isolation often consists of

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wood shavings, newspapers or other material

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that can easily ignite.

0:00:24.839,0:00:26.989
Metal can also lead warmth

0:00:26.989,0:00:29.540
and start a fire at a completely different

0:00:29.540,0:00:31.060
place than on the roof.

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Therefore you should bring tools

0:00:32.897,0:00:35.145
you can use to remove planks and tiles with,

0:00:35.145,0:00:37.590
since these places are difficult to reach.

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Roofing with an open flame is also

0:00:40.584,0:00:42.442
regulated in the safety regulation:

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It is prohibitied to use open flame

0:00:45.163,0:00:47.595
on lined and ventilated wooden roofs.

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On compact roofs open flame is permitted

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if flammable insulation is protected with

0:00:52.888,0:00:55.989
at least 30 mm non-combustible insulation.

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There must be a safety distance of 60 cm

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to parapet, cornice, ducts and so on

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if thes consist of combustible material.

0:01:06.794,0:01:09.082
Hot air is a lot safer than

0:01:09.082,0:01:10.342
open flames.

0:01:10.775,0:01:12.263
Here the warm gas and air is

0:01:12.263,0:01:13.916
shielded in a chamber.

0:01:13.916,0:01:15.885
The biggest risk with this equipment

0:01:15.885,0:01:18.584
is that it produces a lot of carbon dioxide

0:01:18.584,0:01:19.896
that displaces the oxygen.

0:01:20.506,0:01:22.629
When you are done and turn off the equipment

0:01:22.629,0:01:24.165
oxygen-rich air rushes back,

0:01:24.165,0:01:27.594
which can lead to ignition.

0:01:29.188,0:01:32.107
Roofing can also be done with hot bitumen.

0:01:32.107,0:01:34.369
Gas-fired bitumen boilers are used

0:01:34.369,0:01:36.875
in order to heat the asphalt to 200 degrees celcius.

0:01:36.875,0:01:39.135
Here the bitumen boiler is the main risk,

0:01:39.135,0:01:40.720
not the roofing.

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It can overheat,

0:01:42.456,0:01:44.000
causing the bitumen to ignite.

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Or warm bitumen can spray out of the boiler.

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When using a bitumen boiler you must follow these rules:

0:01:52.838,0:01:54.850
The bitumen boiler must be placed on a non-combustible

0:01:54.850,0:01:56.046
and level base,

0:01:56.046,0:01:57.386
for example in a vessel,

0:01:57.386,0:01:58.903
that can hold at least half of the

0:01:58.903,0:02:00.455
content in the boiler and is at least

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30 cm wider than the boiler on all sides.

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The boiler must always be placed

0:02:05.460,0:02:07.432
where it cause the least possible risk

0:02:07.432,0:02:09.639
if it overheats or tips over.

0:02:10.457,0:02:13.240
The boiler must be supervised at all times.

0:02:14.460,0:02:16.997
Flammable material in the vicinity must be removed.

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On sloping grounds the boiler must be at least

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15 meters from flammable material.

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And at least 5 meters from

0:02:26.492,0:02:29.368
buildings in non-combustible materials.

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Gas cylinders must be placed at

0:02:32.022,0:02:34.231
least 5 metes from the boiler.

0:02:35.509,0:02:36.717
Fire in a boiler must

0:02:36.717,0:02:38.362
never be put out with water.

0:02:38.362,0:02:39.634
If water comes in contact with

0:02:39.634,0:02:40.738
the burning bitument,

0:02:40.738,0:02:42.679
it can be thrown out of the boiler

0:02:42.679,0:02:44.671
with great power.