People living nearby the notorious smelly tip have been reassured there is no need to stay indoors.
Residents have long been complaining about foul smells issuing from the Clayton Hall tip in Whittle-le-Woods.
But although unpleasant, the smell does not have any health risks, says Chorley Council.
A council spokesman said: "On Friday we started to receive quite a few calls about a change in health advice that people needed to stay indoors and shut their windows and doors.
"We just want to reassure people that there is no change in the health advice and people do not need to stay indoors."
The Environment Agency is currently monitoring the emissions.
They say that the results have now been analysed by Public Health England and all except one reading has been below the World Health Organisation (WHO) air quality guidelines. The presence of hydrogen sulphide below the levels set by the WHO means there will be no long-term harm to health.
The Agency added that at the levels recorded there may be an odour, and it is recognised that odour is a nuisance and can cause stress and anxiety. Some people may experience symptoms such as nausea, headaches or dizziness even when a substance that causes the smell is below a level established to protect from harm to health.
Councillor Alistair Bradley, Leader of Chorley Council, said: “I share the residents’ concerns about this issue and we’ve been doing all we can to get those responsible to get it sorted as soon as possible.
“It’s important we all work together to get rid of the smell and once the problem is fixed we need to find out why it happened and make sure steps are taken so residents don’t have to suffer like this again.”