While India is yet to act...

Europe has standards since 1980s

ODOUR-HOUR: Assessment is done based on number of hours in a year when odour was recognisable for at least 6 minutes. The permissible limit is 10% odourhours in residential areas and 15% odour-hours in industrial areas. The standard is followed by Germany and Austria

HOURLY MEAN APPROACH:

Odour threshold value cannot exceed 2% of the total hours in a year (175.2 hours). It is also called the 98th percentile of hourly averages and is followed by France, Ireland, the Netherlands

EUROPEAN ODOUR UNIT (ouE):

During odour detection, the threshold at which 50% of panlists can smell the odour is 1 ouE/m3. In

Italy, which follows the unit, the limit is 2 ouE/m3 in residential areas; 3 ouE/m3 in commercial areas.