It’s been almost a year since the September 13, 2018 gas explosion in Boston, MA that killed one person and forced the evacuation of 30,000 people from their homes.

The series of explosions and fires affected approximately forty homes. The cause was determined to be excessive pressure in natural gas lines owned by Columbia Gas of Massachusetts.

Since then, utility companies have been pushed to improve safety and update old infrastructure—an expensive proposition.

Cities that have replaced the often century-old pipelines have significantly fewer gas leaks. However, replacing old pipe with new can cost as much as $1.9 million per mile. About a third of Massachusetts’s gas pipeline system is leak-prone and old.

While a widespread series of explosions like the one in Massachusetts is incredibly rare, natural gas explosions are not. In 2010 in San Bruno, CA, an electrical failure sent high-pressure gas into an old and faulty pipeline, creating a deadly fireball that killed eight people and destroyed 38 houses.

Across the U.S. there are about 286 serious natural gas explosions per year—the type that cause over $50,000 worth of damage, severe injury, or loss of life. Between 1998 and 2017, 15 people per year on average died in incidents related to gas distribution in the U.S.

These explosions have left many people wondering if natural gas is safe. How do natural gas explosions happen? And is there anything they can do to help prevent a future occurrence?

How do natural gas explosions happen?

Natural gas is delivered to homes and businesses across the country through long-distance, high pressure pipelines. These lines are separated by a valve into lower-pressure pipelines that connect to buildings.

While local gas pipelines are designed to withstand two-to-three-times their usual operating pressure, once this limit is reached, there is a much higher likelihood of gas escaping and leading to an explosion. It’s this excess pressure that is believed to have caused the Massachusetts explosions last year. Gas escaped into homes and was ignited by a source within the home, such as the pilot light.

When excess pressure is to blame, it’s common for the cause to be a failure at the valve that separates the high pressure and lower-pressure pipelines. It could be from a leak or a break—which is especially common in cities with older pipelines.

However, human error is, unfortunately, the most common reason for the failure. In 2005, a house exploded in Lexington, MA, when a gas company worker connected a high-pressure gas line to a low-pressure line by accident.

How can you prevent a natural gas explosion from occurring?

1. Annual inspection and leak survey.

Having your gas pipelines inspected regularly is one of the best preventative measures you can take to avoid natural gas leaks and explosions. Our natural gas inspection services consist of an odor test, proper valve operation, above and below ground piping inspection, leak surveying, gas system mapping, and line locating.

An annual leak survey is now an Arizona Corporation Commission requirement for all properties that have a Master Meter Gas system. RP Gas Piping can complete your Annual Master Meter Inspection and can undertake any repairs necessary to make you ACC compliant. Learn more about what this means for owners of master meter gas systems.

2. Know what to do if you smell gas.

There are four signs that could indicate you might have a small natural gas leak, and it’s time to repair your gas piping:

• A strong smell of gas inside your home or building (an unmistakable sulfur-like smell, often described as a “rotten egg” smell).
• Dead plants in the area of a gas line.
• Hissing sound.
• White cloud or dust cloud near a gas line.

If you suspect a gas leak, follow these six steps immediately.

3. Recognize when it’s time to repair or replace a gas line.

Due to the natural erosion process, some natural gas pipes eventually need to be repaired or replaced. Being proactive—testing, maintaining, and repairing your gas piping—is essential for preventing any long-term damage to your valuable assets and livelihood. Learn the 4 signs you might need a gas line repair or repipe.

4. Be aware of where natural gas lines are on your property.

It’s important to have a full understanding of all the sources of natural gas on your property for two key reasons:

• If an unknown natural gas line leaks outside or inside a wall and you are not aware that the line exists, it can be very dangerous and potentially deadly.
• You could end up paying a large sum of money, not only for the leaked gas over time, but also to repair the leak.

5. Call before you dig.

You must, as required by Arizona law, call Arizona 811 to mark any underground gas lines. It is a free service that must be completed before any type of digging begins. However, utility companies and local governments mark only what they own and operate. They recommend using a private company for private locating services.

RP Gas can help with locating buried natural gas lines on residential and commercial properties in Arizona.

Natural gas is a popular option for most homeowners in Arizona, and if used properly, it’s completely safe. RP Gas Piping is an Arizona statewide natural gas pipeline contractor with a crew of professional staff, and highly qualified certified Natural Gas Technicians at your service.

We focus on delivering efficient installations and compliant repairs to all natural gas system needs.