Conversion of concentration unit ppm and Mg / m3: calculated by the following formula: mg/m3=ppm·M/{22.4·[273/(273+T)]X（Ba/101325）} Or mg / m3 = (M / 22.4) * ppm * [273 / (273 + T)] * (BA / 101325) Which algorithm is correct?

Conversion of concentration unit ppm and Mg / m3: calculated by the following formula: mg/m3=ppm·M/{22.4·[273/(273+T)]X（Ba/101325）} Or mg / m3 = (M / 22.4) * ppm * [273 / (273 + T)] * (BA / 101325) Which algorithm is correct?

The latter is right!
The former may be wrong
The scope of use is to calculate the air, the unit of the calculated result is g / L, and the result should be multiplied by 1000
I checked and calculated a result. The result measured by the machine is 100ppm carbon dioxide, room temperature 20 ℃, 80kPa air pressure (Yunnan as an example). The calculated result is about 0.921g/l, which is unlikely. If you change the unit and multiply 1000, the result is 920mg / m3

How to convert mg / m3 to ppm?

Ppm for gas: the volume of contaminant in one million volumes of air
According to China's regulations, especially the environmental protection department, the gas concentration is required to be expressed in the unit of mass concentration (such as mg / m3),
Our national standards are also expressed in mass concentration unit (such as mg / m3)
Conversion of PPM and Mg / m3: mg / m3 = m / 22.4 × ppm × (273 / (273 + T)) × P / 101325
Where m is the molecular weight of the gas, t is the temperature, P is the pressure, and M is the mass of the gas (in mg)