Triangle NoTES — March 2016

Discussion of issues clients found with other sources for equipment and analysis during the period we were not an independent laboratory.

What has been so surprising to the people who, for whatever reason, had to use an alternative source for their analysis is the way things are done elsewhere.

The worst complaint was that the methods had been modified but that there had been no specific information provided for the modifications before the project was started. Once the results were submitted and questions were asked the modifications came to light. The problem was the modifications precluded the agency accepting the results thereby forcing a complete re-sampling of the source.

A close second was the dearth of information in the report, which consisted of essentially a table of results, a sparse narrative and a copy of the COC. This is a far cry from getting all of the data from area counts at the analyzer, response factors, dilution factors, sample calculations for every step and every piece of data for every sample should anyone wish to check the calculations. Over the years we have added more data to the report if even one regulatory agency requested it after receiving our report. We strive to have any data already in the report so if there is ever a question the answer is already available and documented. I know the program being use for calculations has been checked and the results verified by everyone here, a multitude of clients and regulators, and several auditors, but it never hurts to have just one more person follow up.

The one issue that completely surprised me was one I thought had been so completely discussed that everyone knew about it, which was making sure the return shipments were shipped legally and with as few problems as possible.

While it sounds a little counter-intuitive, if you meter 5 L of sample into a 6 L canister the volume of the sample is 6 L not 5 L. This is because the gas expands to fill the container albeit at a lower pressure. That is the reason we have the ability to determine the effect on the variables of pressure and volume when the temperature is constant. Using the formula P1V1 = P2V2 we can see how the pressure changes proportionally as the volume is changed. For example, a 3 L container with an absolute pressure of 760 mmHg will have an absolute pressure measurement of 380 mmHG if it is introduced into a 6 L container using this formula. The volume increased and the pressure in the container decreased. The inverse is also true, which means if the 6 L container had an absolute pressure of 760 the same sample in a 3 L container would have 1520 mmHg of pressure. The DOT defines volume of a gas sample as that of the container in which it is shipped as long as the absolute pressure of said gas is less than 15.22 psia per 49 CFR 173.306 (a)(4). Although most law enforcement agencies are not aware of the regulations or fines, the DOT has allowed anyone authorized to issue a travel citation to issue a citation for improper transportation of sample containers since 1988. This includes any state, county, city, or town police officer which may for any reason stop a vehicle for a travel violation. This includes personal and company vehicles in the potential for receiving a fine, but still not as likely to be fined as with a common carrier either.


Triangle Environmental Services, Inc.

(919) 361-2890        (800) 367-4862            FAX: (919) 361-3474