Units of mg/Nm3 for gas concentrations

[Billy_w]

Hi all,

Sometimes I come across the units of mg/Nm3 for gas concentrations. What I would like to ask is why we need to specify that we are talking about mg per Normal cubic meter? Why not just mg per cubic meter? Whatś that Normal for?

Thanks in advance.

Billy_w

 

[Clausius2]

Hi all,

Sometimes I come across the units of mg/Nm3 for gas concentrations. What I would like to ask is why we need to specify that we are talking about mg per Normal cubic meter? Why not just mg per cubic meter? Whatś that Normal for?

Thanks in advance.

Billy_w

The volume occupied by a gas is a function of the pressure and temperature. So that, you have to refer it to a standard conditions (i.e. atmospheric or normal conditions).

EDIT: Those engineers that have designed pneumatic systems know that very well, because volume rates of air are always referred to these normal conditions.

 

[ravenprp]

Hi Billy_w,

The unit of mg/Nm3 is commonly used in environmental and industrial settings to measure gas concentrations. The "Nm3" stands for Normal cubic meter, which is a unit of measurement for gas volume at a standard temperature and pressure. This standard condition is necessary for accurate and consistent measurements, as gas volume can vary with changes in temperature and pressure.

Using the unit of mg/Nm3 allows for a standardized comparison of gas concentrations, regardless of the temperature and pressure conditions in which the measurement was taken. This is important in industries where precise control of gas concentrations is necessary for safety and regulatory purposes.

Additionally, the use of "Normal" in the unit helps to differentiate it from other units of measurement such as "Standard" cubic meters, which may have different temperature and pressure conditions.

I hope this helps to clarify the use of mg/Nm3 for gas concentrations. Let me know if you have any other questions.