AS ISO 16900.3:2015 pdf download.Respiratory protective devices—Methods of test and test equipment Part 3: Determination of particle filter penetration.
7.2 Aerosol generator
7.2.1 General
Sodium chloride (NaCI) aerosol shall be neutralized by the injection ol both positive and negative ions into the drying or dilution air flow so that the charge distribution is brought to the state of equilibrium, commonly known as the Boltzmann distribution. Paraffin aerosol shall not be neutralized since this increases variability in the test results.
NOTE The ions should be generated by electrical means and adjusted so that there is no overall charge bias on the aerosol.
7.2.2 Sodium chloride test method
7.2.2.1 The test aerosol is generated by atomising by compressed air a solution of sodium chloride in dernineralized water. The atomized solution is mixed with dry air to cause the water to evaporate, The resultant aerosol shall have the following properties:
a) the number median of particle size distribution is between 0,06 pm and 0.10 pm electromobility
diameter, with a geometric standard deviation between 1,4 and 1,8;
b) the aerosol concentration is within the range 8 mg/m3 to 35 mg/rn3
c) the variation of the concentration is not greater than ±10 % during the test;
d) the relative humidity is 40 % or less at (22 ± 3) °C.
The aerosol mass concentration, particle size distribution and humidity shall be measured within the filter test chamber.
7.2.1 General
Sodium chloride (NaCI) aerosol shall be neutralized by the injection ol both positive and negative ions into the drying or dilution air flow so that the charge distribution is brought to the state of equilibrium, commonly known as the Boltzmann distribution. Paraffin aerosol shall not be neutralized since this increases variability in the test results.
NOTE The ions should be generated by electrical means and adjusted so that there is no overall charge bias on the aerosol.
7.2.2 Sodium chloride test method
7.2.2.1 The test aerosol is generated by atomising by compressed air a solution of sodium chloride in dernineralized water. The atomized solution is mixed with dry air to cause the water to evaporate, The resultant aerosol shall have the following properties:
a) the number median of particle size distribution is between 0,06 pm and 0.10 pm electromobility
diameter, with a geometric standard deviation between 1,4 and 1,8;
b) the aerosol concentration is within the range 8 mg/m3 to 35 mg/rn3
c) the variation of the concentration is not greater than ±10 % during the test;
d) the relative humidity is 40 % or less at (22 ± 3) °C.
The aerosol mass concentration, particle size distribution and humidity shall be measured within the filter test chamber.
