These indicators should be calibrated according to National Institute of
Science and Technology (NIST) specifications.
Test for Aerosol Penetration
Requirements and Test Equipment
12.1.1 In a test carried out to determine the level of respiratory protection provided
by the supplied-air suit, a suit tester should wear the suit, which is connected
to a source of air, in an atmosphere containing a non-toxic test agent. The
penetration of the test agent into the helmet of the supplied-air suit should be
measured as the suit tester carries out various exercises. In tests carried out to
determine the level of respiratory protection of the supplied-air suit, each of
the three test subjects should wear the supplied-air suit.
12.1.2 The test atmosphere to be used to determine the level of respiratory
protection provided by the supplied-air suit should be a polydisperse aerosol.
The aerosol particle size and concentration should be measured before and
after each series of tests, by appropriate methods and recorded.
12.1.3 Appropriate monitoring equipment and accessories should be used to detect
the aerosol particles in the test atmosphere and inside the helmet of the
supplied-air suit. A suitable recorder should be used to record penetration
12.1.4 A chamber containing the test atmosphere should be used to carry out tests to
determine the level of respiratory protection provided by the supplied-air suit.
The chamber should be of suitable size to permit a suit tester wearing the
supplied-air suit to carry out freely the various prescribed exercises.
12.1.5 A probe, located inside the chamber and connected by means of tubing to the
aerosol detection equipment device, should be used to sample the test
atmosphere. A probe located inside the helmet of the supplied-air suit should
be used to sample the air from the suit tester's breathing zone. The helmet
probe may be inserted through the supplied-air suit's helmet or be passed
through openings inherent to the supplied-air suit's design (i.e., two-piece
12.1.6 The rate of flow of sample air from the chamber and from inside the helmet
of the supplied-air suit should be within the range specified by the
penetrometer's manufacturer and ideally be selected to determine the
maximum protection factor feasible.
12.1.7 The maximum length of breathing air hose, provided with the supplied-air
suit, should be used in carrying out the tests to determine the level of
protection provided by the supplied-air suit. A suit tester upon entering the
test chamber should connect the breathing air hose to a fitting located inside
the chamber that is connected to a source of air. An airflow control valve and
a calibrated airflow-measuring instrument should be used to control the flow
of air to the supplied-air suit worn by the test subject inside the chamber and
to measure the rate of flow of this air.