Instruction Manual

10
Post-weighing for Inhalable and Respirable Fraction
Wear powder-free gloves when handling casse es and use forceps
when working with fi lters.
1. Equilibrate plastic casse e, fi lter, and foam for a reasonable time based on
humidity conditions.
2. Remove the casse e from the transport clip or sampler housing body. The
casse e cover can remain on the casse e if it was included in the pre-weight.
Before proceeding, see table on Pre and Post-weighing for Specifi c Fractions on
page 4. Weigh the casse e with fi lter and foam disc together. Record post-weight
#2. Compare pre-weight #2 to post-weight #2. The diff erence between weights
is the amount of inhalable particles collected.
3. Gently split the casse e apart (see Filter Casse e: Opening, Installing Filter, and
Closing on page 4), taking care not to dislodge the fi lter.
4. Before proceeding, see table on Pre and Post-weighing for Specifi c Fractions on
page 4. Weigh the casse e bo om with fi lter only.
5. Record post-weight #1. Compare pre-weight #1 to post-weight #1. The diff erence
between weights is the amount of respirable particles collected.
The IOM casse e can be cleaned, reloaded with a fresh fi lter and foam, and reused.
See Cleaning the Sampler on page 3.
Chemical Analysis
Follow method instructions for sample preparation and analysis.
Bioaerosol Sample Extraction
1
and Analysis
1. Using sterile forceps and gloves, remove the casse e from the transport clip.
2. Gently split the casse e apart; do not dislodge the fi lter.
3. Remove the foam and fi lter from the casse e.
Push foam down through the fl anged end of the casse e, not
through the inlet.
4. There are two methods for extracting the sample from the MultiDust Foam Disc
and the fi lter.
a. Method 1
Place the foam and the fi lter in individual vials each fi lled with 10 ml of
Peptone Inositol Tween (PIT). When analyzed, this method provides data
on inhalable and respirable bioaerosol fractions.
b. Method 2
Place fi lter and foam together in a vial fi lled with PIT. When analyzed,
this method provides data on the inhalable fraction only of the bioaerosols
collected.
5. Create a suspension.
a. Using Method 1 with fi lter only: Whirlimix the fi lter in PIT for one minute
to re-suspend collected particles.
b. Using Method 1 with foam only: Whirlimix the foam for one minute, and
then plunge rapidly for one minute in situ using a sterile 20-ml hypodermic
syringe plunger.
c. Using Method 2 with foam/fi lter combined: Whirlimix the foam for one
minute, and then plunge rapidly for one minute in situ using a sterile
20-ml hypodermic syringe plunger.