Weather Conditions Allegedly Cause Propane Tank To Explode

This case involves a group of people that were injured by a propane tank explosion at a local street fair in California. The fair took place on an incredibly hot and sunny day with no cloud coverage. The tank in question was being used by a food vendor near the center of the fair. The tank had been placed directly on the hot asphalt and was running for several hours. Around 2 pm, the tank exploded injuring some of the food vendors and a group of people passing by the vendor. It was alleged that the weather conditions caused the propane tank to explode. An expert in meteorology was sought to discuss the temperature and heat index of the day in question and how the propane tank was affected by the heat.

Question(s) For Expert Witness

1. Please describe your background in meteorology.

2. How would you determine what the temperature and heat index was on the day in question and how they affected the tank?

Expert Witness Response E-099958

I have been an educator for 16 years in meteorology. What matters is the temperature of the contents inside the tank. This is a function of the ambient air temperature and whether the tank is exposed to direct sunlight. The heat index would not be relevant. From what I understand, these tanks are designed to be able to withstand quite a bit of heat and direct sunlight (they are commonly exposed to direct sunlight if used for backyard BBQs, for example). If they become dangerously hot, the tanks are supposed to have a safety feature such that gas is vented automatically through a valve so that no explosion occurs. It would seem to me that if an explosion occurred, this would indicate either that the valve was faulty or else the tank was exposed to conditions that exceeded the capabilities of the built-in safety features.