develop consensus standards for use by TNI's programs. This group has a support role in assisting other programs with activities such as guidance and standards interpretation.
fosters the generation of data of known and documented quality is through the National Environmental Laboratory Accreditation Program, or NELAP. The purpose of this program is to establish and implement a program for the accreditation of environmental laboratories.
is to establish and maintain a national PT program to support TNI’s National Environmental Laboratory Accreditation Program, and other activities.
Field Activities Program (NEFAP) Executive Committee is to establish and implement an accreditation program for field sampling and measurement organizations (FSMOs).
Audit Sample Program is to develop consensus standards for the manufacture and analysis of audit samples for source emission testing.
on a variety of topics of interest to the environmental measurement community. TNI also hosts two regularly scheduled meetings per year, typically in January and August. Both are a week long and involve open meetings of TNI committees as well as training courses and other special sessions.Standard Interpretation
Standard: 2016
Section: V1M5, Section 1.7.3.7.b.ii.a.4
REQUEST:
This section states that "... When it has been determined that the autoclave has no leaks, pressure checks can be documented using the formula PV = nRT."
Every resource we can find states that saturated steam does not behave as an ideal gas and we are unable to match results from this formula to actual observed results.
Is this portion of this requirement still considered to be realistic and if so, are there resources available to clarify how this should be used and reported?
TNI FINAL RESPONSE:
Since PV=nRT, checking the temperature and assuring no leaks (so that V is constant) is sufficient to meet the requirements of the standard. Although saturated steam does not behave as an ideal gas, if the temperature is checked and the volume is constant and there are no leaks, the pressure is verified.
The Standard does not require this approach but provides it as an option for laboratories who are performing pressure checks on their autoclaves.
In addition, V1M2 5.5.13.1.a and V1M2 5.5.13.1.b of the 2016 TNI Standard are applicable to this SIR.
The second part of the submitter's question is asking for a "how to" rather than an interpretation.