EPA-NERL: 160.2:  Non-filterable Residue by Drying Oven

  • Summary
  • Analytes
  • Revision
  • Data and Sites
Official Method Name
Residue, Non-Filterable (Gravimetric, Dried at 103-105 oC)
Current Revision
Issued 1971
Method Subcategory
Method Source
  Methods for the Chemical Analysis of Water and Wastes (MCAWW) (EPA/600/4-79/020)
Brief Method Summary
A well-mixed sample is filtered through a glass fiber filter, and the residue retained on the filter is dried to a constant weight at 103-105oC.
Scope and Application
This method determines non-filterable residue in drinking, surface, and saline waters; domestic and industrial wastes.
Applicable Concentration Range
4 - 20,000 mg/L
(A) Procedure: Filtration apparatus, filter material, pre-washing, post-washing, and drying temperature are specified because these variables have been shown to affect the results.
(B) High Residue Levels: Samples high in Filterable Residue (dissolved solids), such as saline waters, brines and some wastes, may be subject to a positive interference.
Filters: Care must be taken in selecting the filtering apparatus so that washing of the filter and any dissolved solids in the filter (7.5) minimizes this potential interference.
Quality Control Requirements
Sample Handling
Non-representative particulates such as leaves, sticks, fish, and lumps of fecal matter should be excluded from the sample if it is determined that their inclusion is not desired in the final result. Preservation of the sample is not practical; analysis should begin as soon as possible. Refrigeration or icing to 4oC is recommended.
Maximum Holding Time
7 days (MCAWW, Table 1).
Relative Cost
Less than $50
Sample Preparation Methods