parts per million


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parts per million

The parts of a substance per million parts (by weight) of a solution; equal to 0.0001%. Abbr. ppm.
References in periodicals archive ?
Carbon dioxide levels reached as high as 1,400 parts per million on five percent of airline flights the European Aviation Safety Agency tested, according to data it released last year.
The city of Portland also becomes a colorful presence in Parts per Million, fostering its well-known culture of protest and spirited nonconformity.
Vranka said EPA doesn't know how the sand play area could have less than 70 parts per million in 2003 and 725 parts per million in 2017.
"It was only a matter of time that we would average 400 parts per million globally, "said Pieter Tans, lead scientist at NOAA's Global Greenhouse Gas Reference Network.
Levels are now growing about 2 parts per million per year - 100 times faster than at the end of the Ice Age.
The study by researchers based at the National Oceanography Centre, Southampton determined the 'natural equilibrium' sea level for CO2 concentrations ranging between ice-age values of 180 parts per million and ice-free values of more than 1,000 parts per million.
Anomalous geochemistry includes 13 parts per million uranium over 49 metres, 406 parts per million vanadium over 30 metres and 1,186 parts per million boron over 250 metres, including up to 2.69 per cent boron over 10 metres.
45 in Brooklyn ballasts were found with PCB levels of up to 660,000 parts per million, a massive amount compared to the EPA's regulatory limit of 50 parts per million.
The nonprofit Center for Biological Diversity is aiming to gather 500,000 signatures that will be delivered to the Environmental Protection Agency to set an upper limit of 350 parts per million on allowable greenhouse gas pollution.
IEA says use of fossil fuels must peak by 2020: The use of fossil fuels must peak by 2020 to keep atmospheric concentrations of greenhouse gases below 450 parts per million and avoid catastrophic climate change, according to the International Energy Agency.
The Sun newspaper said 93 parts per million were discovered in the fur of the Mr Squiggles version - and 106 parts per million in its nose.
Reports said 93 parts per million were discovered in the fur of the Mr Squiggles version -and 106 parts per million in its nose.