CSST vs. Black Iron Pipe

For decades, schedule 40 black iron pipe was the default choice for piping gas to furnaces and water heaters. But in the United States, there are about 24 people killed every year in fires caused by leaks or breaks in the natural gas or propane systems.[1]  Incidents causing injury, death, or property damage over $50,000 happen about 286 times a year.[2] Many deaths are caused by leaking gas that lead to explosions. That is why an alternative to black iron pipe was developed—corrugated stainless steel tubing (CSST). First developed in Japan to solve the dangers of broken rigid gas piping in an earthquake, and then brought to the United States by the American Gas Association (AGA) and the Gas Research Institute (GRI) in the United States as an alternative gas piping solution, CSST was developed to eliminate the difficulties and dangers of rigid gas piping.

Rigid pipe presents a variety of problems:

The rigid pipe joints are a well recognized cause of gas leaks and fires. The National Fire Protection Association (NFPA) publishes the Guide for Fire and Explosion Investigations (NFPA 921), and notes in Chapter 9 that joints and fittings in rigid pipe systems are the most common sources of gas leakages and gas fires and explosions:

Leaking joints in a rigid pipe system can cause an accumulation of fuel gas and a resulting explosion. Alternatively, leaking gas can ignite from an open flame or pilot light or other ignition source.  Below are a few incidents recorded from government investigations and news media.


Hatboro PA – 6 people dead from gas explosion caused by broken black iron pipe – caused by flooded basement.

On June 16, 2001, an explosion occurred at the Village Green Apartments complex in Hatboro, Pennsylvania. The basement in one apartment was flooded due to heavy precipitation from tropical storm Allison. A gas-fired clothes dryer located in the basement of the apartment building was displaced due to water suddenly and rapidly entering the basement. The rigid black iron pipe servicing the dryer cracked at a joint when the dryer floated away, and the crack allowed an unrestricted flow of natural gas into the basement. After a period of nearly three hours, an explosion and subsequent fire occurred, resulting in several personal injuries, and six fatalities.  A re-enactment of the failure mode using CounterStrike CSST proved that it would not have cracked in those same circumstances.  This is one proven example where using CounterStrike CSST would have saved lives.

Atlantic IA – 2 people dead from gas explosion – break

In February 2015, a husband and wife were killed in a gas explosion.  The cause was a leak in the rigid black iron pipe in the basement that the wife used to hand her laundry.  The strain and the stress of the load on the threaded connection over the years caused it to bend and crack, allowing natural gas to leak into the basement.

Dobbin TX – 2 people dead and 1 baby injured in gas explosion – corrosion

On Tuesday, June 11, 2013 at approximately 8: 16 a.m. there was an explosion and fire at the residence of Ms. Lena Knight, 185 N. FM 1486 Dobbins Texas, Montgomery County. One infant and two women were in the house at the time of the incident. All three victims were transported by medical helicopter to the hospital in Galveston, Texas. Both women would later die from their injuries. The residence was totally destroyed from the explosion.  The explosion was caused by a leak in the vertical section of black iron piping that had come up through the kitchen floor and connected to the cook stove was corroded and broken.

Seattle WA – 2 people injured from gas explosion – electricity melted a hole in BIP

On September 26, 2011, a natural gas explosion and fire destroyed a house located at 12312 5th Avenue N.E., in the Pinehurst neighborhood of Seattle, Washington. The incident involved a black iron distribution pipe owned by the local utility.  The homeowners were inside the house at the time of the explosion. One person sustained serious physical injuries from the incident. She was treated for burns over an estimated 40% of her body.  The other occupant received first and second degree bums to his upper torso and face.  The cause of the explosion was natural gas leaking from the pipe located near the foundation of the house. The gas leaked through a one-eighth inch diameter hole in the pipe, which was located where the gas pipe crossed over the sewer pipe that served the house. An electrical arc between the steel gas service pipe and the iron sewer pipe created the hole in the gas service pipe. 

Plymell KS – 3 people dead from gas explosion – cause unknown

On June 28, 2014, a gas explosion destroyed a house in Plymell KS.  The three occupants in the house, a mother and two teenage sons, died from their injuries in the blast.  When the news media attempted to find out what caused the blast, they were surprised by what they found.  Doug Jorgensen, the Iowa State Fire Marshal, said once events are determined to be an accident, his office stops its investigation. Officials ruled the explosion at the Unruh’s home an accident within 24 hours of the blast.  Who is finding out where the gas leak was, what caused the leak, if odor was ever added to the gas, and if the family reported an odor? The State Fire Marshal’s Office is not responsible for keeping track of problems or patterns.  So if the State Fire Marshal’s Office is not responsible for keeping track of problems or patterns, who is? – Quoted from kwch.com, “FF12: Who’s investigating deadly gas explosion?”, Aug. 6, 2014.

People who question the safety of CSST never seem to examine the alternative technology – black iron pipe.  But as you can see, there are numerous injuries and deaths every year from this old antiquated technology.  Every death is a tragedy, and that is why manufacturers are moving to a safer CSST design using the conductive jacketed CSST. In fact, there have been no injuries or deaths associated with Omega Flex’s world-class CSST products.

[1] “Fires Starting With Flammable Gas or Flammable or Combustible Liquid,” John R. Hall, Jr., February 2014, National Fire Protection Association

[2] “Dozens of Massachusetts Homes Exploded. A Gas Expert Weighs In,” Rachel Gutman, Sept. 14, 2018, The Atlantic

[3] Ibid.