Cylinders filled on site must be ____ feet from source of ignition.

Cylinders filled on site must be ____ feet from source of ignition.

• A. 5 feet
• B. 15 feet
• C. 20 feet
• D. 10 feet

Answer: (D)

When filling cylinders on site, a safe buffer from ignition sources is needed because propane can leak during filling and its vapors flow along the ground. Propane is heavier than air, so those vapors can pool near the surface and reach flames or sparks if they’re too close. A distance of 10 feet provides a practical safety margin that reduces the chance of ignition and allows any minor leaks to vent away from people and ignition sources. Shorter distances, like 5 feet, are too close and riskier, while longer distances such as 15 or 20 feet are more cautious than necessary for typical on-site work. So, 10 feet is the standard balance between safety and practicality.

When filling cylinders on site, a safe buffer from ignition sources is needed because propane can leak during filling and its vapors flow along the ground. Propane is heavier than air, so those vapors can pool near the surface and reach flames or sparks if they’re too close. A distance of 10 feet provides a practical safety margin that reduces the chance of ignition and allows any minor leaks to vent away from people and ignition sources. Shorter distances, like 5 feet, are too close and riskier, while longer distances such as 15 or 20 feet are more cautious than necessary for typical on-site work. So, 10 feet is the standard balance between safety and practicality.