How important is it to eliminate the bubbles within sampling containers, what effect does this have
How important is it to eliminate the bubbles within sampling containers, what effect does this have on sample quality?
There is an excellent paper about a study by Nadim that was published, I believe, in 2001 in Groundwater Monitoring & Remediation, which is the National Groundwater’s publication. In that study, Nadim and his associates looked at the effect of headspace in VOA vials on VOC concentrations and found that the headspace had to be in the order of 10% to 20% of the volume of the vial to effect the concentration of the VOCs in solution. So, that means small bubbles in the bottle shouldn’t make any difference. However, the problems start if you take a sample for VOCs and you turn in a VOA vial to the laboratory that’s got a bubble in it. The laboratory is going to flag that as a bottle with a bubble, and regulatory guidance often indicates that there should be no bubbles in VOC vials. So, bubbles the size of a pea or even the size of a marble would probably make no difference at all in concentration of most VOCs, yet there are permit limits and regulatory limits that are going to prevent using bottles with any bubbles.
There is an excellent paper about a study by Nadim that was published, I believe, in 2001 in Groundwater Monitoring & Remediation, which is the National Groundwater’s publication. In that study, Nadim and his associates looked at the effect of headspace in VOA vials on VOC concentrations and found that the headspace had to be in the order of 10% to 20% of the volume of the vial to effect the concentration of the VOCs in solution. So, that means small bubbles in the bottle shouldn’t make any difference. However, the problems start if you take a sample for VOCs and you turn in a VOA vial to the laboratory that’s got a bubble in it. The laboratory is going to flag that as a bottle with a bubble, and regulatory guidance often indicates that there should be no bubbles in VOC vials. So, bubbles the size of a pea or even the size of a marble would probably make no difference at all in concentration of most VOCs, yet there are permit limits and regulatory limits that are going to prevent using bottles with any bubbles.