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Sewer Gas related Questions

Sewer gases are essentially a mixture of toxic as well as non-toxic gases produced by the decomposition and rotting of domestic waste. It is present in the sewage system and usually a problem with the drainage system in the house. Due to various reasons drainage systems, can result in sewer gases entering the house. When this occurs a nagging doubt may linger in your mind, is sewer gas dangerous as well?

Therefore to know about a few problems related to sewer gas, listed below are a few questions answered by Experts.

Why does the house smell of sewer gas after it rains or when a big load of laundry is completed? Two plumbers suggest a new septic tank..

To begin with, septic tanks should be flushed out once every three to five years depending on the amount of usage. If there is sewer gas smell and if there is gurgling and improper drainage, it is recommended to carry out more frequent pumping. The septic tank company can be asked to test the system as well for proper leaching operation. They would be able to advise whether the tank is functioning properly or not. The roof can also be checked to ascertain whether the vent pipe is clogged (quite unlikely). It can be cleaned using a garden hose.

Could a manhole located on the front yard result in a sewer gas smell to enter the house?

Sewer gas smell experienced could be because of a broken or disconnected vent line which could be in a concealed wall. If this is the case there could be an actual leak in the line with sewer gases as well as actual sewage leak. This may be difficult to locate and determine and should be checked as the last resort. A trap in a used fixture may have lost its trap seal probably because the water in the trap has evaporated. In case of an absence or loss of a trap seal, the action to be taken is to run a little water in all the small fixtures. It would also be wise to check any floor drains present in the basement or elsewhere in the house. In case checking these aspects do not resolve your sewer gas smell, it would be wise to contact a plumber for further inspection.

When it rains, why is there a strong sewer gas smell in bathroom which lasts for 15-20 minutes?

Usually a sewer gas smell in bathrooms is observed when the water from the trap has evaporated allowing the sewer gas to escape through the drain. To confirm if this is the issue, water should be allowed to run in any fixture which has a drain for at least 30 seconds. This action ensures every trap is full. Additionally any unused fixtures should have water poured down them to keep the drain trap full. Another common reason for the sewer gas smell in bathrooms to occur is from the wax seal located at the bottom of any toilet. These wax rings in toilets do not go bad unless the toilet has been shifted, moved or pulled out. At other times the seal could break due to age or rough use. One of the easy ways to determine whether the seal is intact is by checking if the toilet can be moved or tilted. If it can be, then the floor bolts may not be tightened adequately. If this is the case, the toilet would need to be removed to replace the wax seal.

How to detect sewer gas? Is there a sewer gas detector?

There may be sewer gas detectors or sniffers which are essentially methane gas sensing meters that can read parts per million. This allows the scope to detect sewer gas by recording the strength of the meter reading as it nears the source of the sewer gas. Most sewer gas detectors or gas leak detectors are equipped with adjustable sensitivity settings. Hence the sensitivity level can be adjusted to detect even the most miniscule level of methane produced and released.

Sewer gas odor is not only unbearable to endure it may also prove to be dangerous if left unattended. There may be several small steps which can be taken by the home owner to ensure drain traps are filled with water to prevent the escape of sewer gas. However persistent sewer gas smell needs to be treated immediately and effectively. This is where professional help may be sought. Hence an Expert’s guidance in this regard will prove useful and beneficial.
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