02 Natural Gas Facts You Need To Know

Question 1

Flammable Range

Answer 1

The correct mixture of gas in air that will ignite or explode.

Question 2

Flammable Range of NG

Answer 2

5%-15% gas in air

Question 3

Percent of oxygen in air

Answer 3

21%

Question 4

Most fires require what percent of oxygen in air?

Answer 4

16%

Question 5

Exact LEL of NG:

Answer 5

4.4%

Question 6

Ignition temp of NG

Answer 6

1,163 degrees

Question 7

Typical ignition sources of NG:

Answer 7

pilot lights, electronic ignition devices on stoves, boilers, hot water heaters, electrical switches, static electricity, electric door bells, electric motors

Question 8

LD50 (concentration where 50% of the target species are killed) of methane is ___________ for ___________.

Answer 8

539,600 ppm / 2 hours
This concentration is 53.96% gas in air.

Question 9

Vapor density of NG:

Answer 9

0.57-0.62

Question 10

Federal regulations require gas is readily detectable by a person with a normal sense of smell at a concentration of ______.

Answer 10

1/5 of the LEL

Question 11

Can the odorant be scrubbed out?

Answer 11

Yes - as gas passes through soil.

Question 12

Most common odorant for NG:

Answer 12

Mercaptan

Question 13

Tactical actions for consideration:

Answer 13

1. Life safety is FD mission
2. Identify the kill box (ERG says 300’)
3. Park rigs outside of kill box
4. Limit number of FFs in kill box
5. Evacuate civilians as necessary and as quickly as possible. *Evacuation is the primary FD mission

Question 14

According to US Center for Disease Control the odorant is detectable at ______ by most humans.

Answer 14

0.002 ppm

Question 15

According to Rae systems “people can smell the odorant at levels _________ times below the limit of a detection meter.

Answer 15

500,000