Hydrogen sulfide is the odor culprit and never a good sign.


What is Sewer Gas

Sewer gas, at least that which causes an odor problem to the occupants of a house, is a mixture of inorganic gases created by the action of anaerobic (no oxygen required) bacteria on sewage and sludge.  This gas can contain hydrogen sulfide, ammonia, carbon dioxide, and methane.

Advanced Testing for Sewer Gases

When precise analytical data required to understand the issue or locate the source, mr natural has the equipment. mr natural can provide portable gas analysers that are sensitive enough to measure parts per billions. This is essential for tracing odours and getting to the root cause of the problem.

For situations that require analytical data with a higher level of precision to identify gases, a canister or a Teflon bag is used to collect air samples that is sent to the lab for GC/MS (Gas Chromatograph Mass Spectrometer) analysis. This process can measure trace amounts of gases in the nano range.

What Makes it Smell so Bad

Almost always, hydrogen sulfide and methane are the odor culprits, although ammonia may be formed in rare cases.  The rest of the gases listed above are odorless.  The odor threshold, the lowest concentration of hydrogen sulfide that can be detected with the nose, is somewhere between 0.001 and 0.01 ppm (parts per million), an extremely low concentration.

Health Concerns of Sewer Gas

Although hydrogen sulfide is a toxic gas, it may not immediately harm people at the concentrations that exist in a house with sewer gas odor problems however, long-term exposure may result in health effects.  Studies have shown that hydrogen sulfide has a depressant effect on the central nervous system in higher concentrations. Rarely is there enough gas generated in the sewers for concentrations to approach the dangerous level in the dwelling.

After a short period of time, one can be acclimatized to smell hydrogen sulfide and not be aware of its existence or concentrations.

However, if a person were to enter a tunnel or deep hole that contained sewage undergoing anaerobic breakdown, there is a chance he could become poisoned quickly.

Sewer Gas Testing in your Home or Office

Testing for sewer gases can be performed on location with results in minutes. A calibrated monitor with sensors designed to detect hydrogen sulfide, methane and/or ammonia is used to determine the concentrations within the environment. The engineer on site can help you understand the current levels identified, reasons it exists in your home or office and what needs to be done to correct the situation.

Contact an engineer at mr natural® environmental group for information on testing or consulting.