G60 Environmental Considerations 2 — Questions and Answers
Question 1: When using a flammable gas torch near a drain or sewer opening, what is the primary environmental concern?
- Vapors can travel along drains and ignite remotely (Correct answer)
- Drains may corrode from heat exposure
- Water in drains can cause steam explosions
- Drain covers may become projectiles
Correct answer: Vapors can travel along drains and ignite remotely
Flammable gas vapors are heavier than air and can flow into drains, traveling to distant ignition sources and causing remote explosions.
Question 2: Which weather condition most significantly increases the hazard when using a torch outdoors?
- High humidity
- Low wind speed or still air (Correct answer)
- Overcast skies
- High temperature
Correct answer: Low wind speed or still air
Still air allows flammable gas vapors to accumulate near the work area rather than dispersing, increasing the risk of ignition.
Question 3: What environmental precaution must be taken before torch work on a roof with bituminous materials?
- Wet the surrounding roof area
- Check for combustible materials in the space below (Correct answer)
- Increase ventilation by opening skylights
- Apply fire-retardant coating to the roof deck
Correct answer: Check for combustible materials in the space below
Heat from torch work can conduct through the roof deck and ignite combustibles stored or present in the space directly below.
Question 4: How should empty flammable gas cylinders be stored after torch work is complete?
- Laid flat in a cool indoor area
- Upright, capped, outdoors in a ventilated area away from heat sources (Correct answer)
- Stored with full cylinders to save space
- Inverted to drain any residual liquid
Correct answer: Upright, capped, outdoors in a ventilated area away from heat sources
Empty cylinders still contain residual gas and must be stored upright with valve caps on in ventilated outdoor areas away from heat sources.
Question 5: What is the recommended action if torch work must be performed near plastic or PVC piping?
- Increase torch pressure to work faster and reduce exposure time
- Shield or remove the piping before torch work begins (Correct answer)
- Cool the piping with water during torch operations
- Wrap the piping in aluminum foil
Correct answer: Shield or remove the piping before torch work begins
PVC and plastic pipes can release toxic fumes when heated and should be shielded or temporarily removed before torch work.
Question 6: Which of the following best describes the 'fire watch' requirement after torch operations are completed?
- A 15-minute watch immediately after the flame is extinguished
- A minimum 30-minute watch, with the area checked for smoldering materials (Correct answer)
- Watch is only needed if a fire alarm sounded during work
- Watch is required only when working with acetylene, not propane
Correct answer: A minimum 30-minute watch, with the area checked for smoldering materials
FDNY and NFPA standards typically require a fire watch of at least 30 minutes after torch operations to detect smoldering or delayed ignition.
Question 7: What environmental factor must be evaluated when storing gas cylinders on a job site in summer months?
- Cylinders must be kept in direct sunlight to maintain pressure
- Cylinders must not be exposed to temperatures exceeding 125°F (52°C) (Correct answer)
- Cylinders should be buried partially in soil to stay cool
- Cylinders require daily pressure checks in hot weather
Correct answer: Cylinders must not be exposed to temperatures exceeding 125°F (52°C)
Excessive heat raises cylinder pressure and can cause pressure relief valves to open or cylinders to fail, so storage above 125°F is prohibited.
G60 Environmental Considerations 2
When using a flammable gas torch near a drain or sewer opening, what is the primary environmental concern?