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What is Grade 353?

Johnson Test Papers’ Grade 353 filters support inorganic analysis and other forms of instrumental analyses. The low ash content also makes Grade 353 appropriate for gravimetric analyses requiring sample combustion.

  • Very low ash content (0.007% ash concentration maximum)
  • Intermediate pore size of 8 - 12 µm
  • Filtration speed on 20 second according to DIN 53137
  • Particle collection between that of Grades 352 and 354

Johnson Test Papers offers other ashless grades to ensure that you have the appropriate particle retention rating for your needs. Hardened ashless grades are also available for analyses that use strong acid/alkali solutions.

Particle collection and inorganic analysis

Johnson Test Papers’ Grade 353 can be ashed during gravimetric analysis without contributing substantially to the measured weight. These medium-fast filters are appropriate for:
  • Inorganic analysis in the construction, mining, and steel industries for coarser precipitates such as lead, iron and silver sulphide, alkali carbonates, lead chromate, arsenic, antimony and cadmium
  • Particle collection for air pollution monitoring for subsequent analysis by X-Ray fluorescence (XRF) techniques
  • Soil analysis
  • Foodstuffs filtration analysis

Whatman Cross Reference = No.43
Speed class Medium fast filtering
Thickness (mm) 0.17
Pore size (μM) 8-12
Weight (g/m²) 84
Filtration Speed (sec*) 20
Burst Strength (Kg/cm²) < 0.20
*According to DIN 53137
Available Sizes
Diameter (mm) Product Code
55 353055
70 353070
90 353090
110 353110
125 353125
150 353150
185 353185
240 353240
300 353300
320 353320