If you smell ... Gas
Natural gas is odourless, so in order to make it detectable the chemical mercaptan is added, which creates that classic ‘rotten egg’ odour. If you smell gas you could be in danger of a gas leak, which could cause fire or an explosion. Leave the house immediately and call the gas company on your mobile phone or a neighbour’s phone, says Frank Lesh, a building safety inspector. Avoid using a landline phone in the house, turning lights or appliances on or off, or using a car, all of which could create sparks.
If you smell ... Something musty
A musty, pungent odour could indicate a sink leak or broken pipe that has given rise to mould, which loves to grow in dark, damp spots. “For mould we’re really concerned about people with allergies and asthma,” says Dr David Dyjack, an occupational health and industrial hygiene specialist. “Both conditions can be exacerbated by mould exposure.” Disinfect non-porous surfaces like tiles with a ten per cent bleach/water solution and ventilate well, Dyjack adds.
If you smell ... A gross bathroom odour
If your home smells like a waste treatment plant, you could have a leak of sewer gas, which contains toxic and potentially explosive components such as hydrogen sulphide and methane. One cause could be a bathroom that isn’t used often. The pipes under a shower or sink include a U-shaped trap, which holds a small amount of water that blocks sewer gas from leaking back into the house. If a bathroom isn’t used, this water could evaporate, allowing odours through. Another reason could be a broken or clogged vent pipe. In this case call a plumber to investigate.