||Accuracy of Pesticide Reference Standard Solutions. Part I. Factors Affecting Organic Solvent Evaporation.
Hodgson, David W. ;
Watts, Randall R. ;
||Health Effects Research Lab., Research Triangle Park, NC.
Organic solvents ;
Air pollution ;
Standard reference materials
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
A gravimetric experiment was undertaken to identify the factors affecting solvent evaporation from analytical reference standard solutions and to establish the magnitude of the resultant solvent evaporation. The evaporation of organic solvent from standard solutions is affected by: (1) solvent, (2) container type, (3) solution volume, and (4) storage temperature. Solvents with low vapor pressure-to-surface tension ratios have low evaporation rates. Screw-cap containers with precision-made caps and seals have the lowest evaporation rates. The use of large-volume standard solutions reduces the percent solvent loss. Storage at refrigerator or freezer temperatures can reduce evaporation rate by as much as a factor of 7.