GAS/Steam Flashcards
Natural gas is made up mostly of what?
Is it lighter or heavier than air?
What is the explosive range?
Mostly methane
Lighter than air
5-15% is the explosive range
Is natural gas toxic?
How many cubic feet equal 1lb of dynamite?
Where are national grid ID tags for gas covers? ConEd?
It is non-toxic, its an asphyxiant
2 cubic feet equal 1lb of TNT
National grid tags are on north side of cover (stamped), ConEd has tags on the inside of the cover
Gas
Can you have plastic piping inside a building?
When can round covers be removed?
No plastic piping in a building
Round sewer covers can be removed by orders of IC
Round electrical covers can be removed when requested by utility company, approved by chief, and ConEd test for stray voltage.
*do not pull square or rectangular covers
GAS
Where do you make your report for the LEL from?(inreference to room)
What is the first priority? Second?
Make LEL report from high and in the center of room where leak is suspected
1st priority make sure its not a major gas emergency
2nd mitigating minor leak
What signal to do you give for a major gas leak?
An outside leak, do you let it naturally vent or should you use a fog stream?
How do you mark a potential blast zone?
10-75 and 10-80 code 1
Let outside leaks naturally ventilate
Use red tape to mark potential blast zone
*announce boundaries over dept radio
Can you operate inside a structure if the leak is found an LEL is at 75%? Can you operate inside a structure if the leak is not found and the LEL is at 15%?
If leak is found and LEL can be kept below 80% LEL by venting you can still operate.
If leak is NOT found and LEL can be kept below 10% by venting you can still operate.
Can you enter a potential blast zone to move a Rig?
When preforming rapid evacuation what other actions can you take?
When in the potential blast zone can you force a door?
Do not enter to move a rig
Do not take any other actions during rapid evacuation other then evacuating
You can force a door in a potential blast zone if a known life hazard, only use adz end
At what LEL do you start rapid evacuation?
80% LEL for leak location known
10% LEL for leak location unknown
MSA ALTAIR How long to power on What is normal LEL readings? O2 reading? When does it alarm? Who do you call for replacement?
40sec to power up
0% LEL and 20.8% O2 are normal
Alarms at 10%LEL and 19.5% and 23.5% O2
Call Hazmat ops for replacement, does not go thru the bag
Altair
What does XXX mean? +++?
XXX= atmosphere is at 100% LEL or higher \+++ = O2 levels greater than 30%
Sensit How long to charge? Who do you call to swap? If it intrinsically safe? Can detect source as low at \_\_ppm
2-5hrs to charge
Call Hazmat ops to swap
Is intrinsically safe
As low as 20ppm
Intrinsically safe fans Can they be used for positive pressure ventilation? Is the whole system intrinsically safe? Where is the grounding cable attached What do you do first plug in or turn on?
Not for positive pressure vent
Only the motor is intrinsically safe
Grounding cable attached to body of fan
Plug in before turning on
Steam How can you identify a vault? Water slug can travel how fast? Generating plants can reach what PSI, what temp? Buried supply lines what PSI and Temp?
Concrete slab with pair of access manholes
Slug goes 200mph
Generating plants 2,000psi , 900degrees
Supply lines 170psi, 350degrees
Steam
When can you enter a conEd generating plant?
HELB can project debris how fast?
Can members shut valves on the outside of buildings?
Only enter plant with conEd personnel and for search and rescue of plant personnel. Plant personnel will mitigate emergency
HELP can project debris at 200mph
Do not shut valves on outside of building, in an emergency you can shut inside service valve, do not randomly shut valves inside a supplied building.
GAS
What would be a major gas emergency?
10-20 VOIDS
10% LEL inside or outside
20% LEL in an unvented substructure
Void or inside wall has gas leaking in it
Outside source leaking into building
Inoperable or unable to locate control valve
Damage (serious) to critical infrastructure
Subsurface (2 or more) structure will gas
