Yes. The 2008 revision bulletin of The United States Pharmacopeial (USP) Convention states: “All cleaning materials, such as wipers, sponges, and mops shall be
nonshedding, preferably composed of synthetic
micro fibers, and dedicated to use in the buffer or clean area, ante-area, and segregated
compounding areas and shall not
be removed from these
areas except for
requiring validation documentation that the
wipers in use were
is the particle contamination level data
generated by the wiper
manufacturer that is
entered on the Certificate
of Analysis accompanying
each lot of wipers manufactured.
It should be noted that there is
no recognized test, procedure, or recommended
practice that can be performed to determine the
correct wiper for a particular cleanroom, process,
or activity. The final choice rests with the user
in this determination. A wiper may be chosen
because of its unique performance properties like
the heat resistance found in cotton wipers, but if
the wiper is used in an ISO Class 3 cleanroom,
a wiper with such a high contamination level
would likely not be found.
Wiper selection is based on many factors.
The wiper contamination characteristics may
be determined as described in the IEST recom-
mended practice, IEST-RP-CC004.3, Evaluating
Wiping Materials Used in Cleanrooms and
Other Controlled Environments. These con-
tamination characteristic factors are the particle
and fiber, non-speciated extractable matter and
ionic contaminant contamination levels. Other
factors, which may be more elusive to quantify,
are the users’ process needs, the impact of the
activities (e.g., cleaning spills and surfaces or
holding manufactured parts or
pieces) in the cleanroom, and
the impact to product yield
and manufacturing costs.
These factors affect the
type of wiper needed
to achieve appropriate
cleaning and contami-
During the clean-
ing validation, all
of the wiper char-
for the surfaces
to be cleaned while
activities are performed.
Pre-saturated wipers can be
purchased with selected cleaning agents.
It is important that the bulk of the cleaning
agent liquid remains within the wiper so as to
minimize the contamination of the cleanroom
from the cleaning agent and not to cross-con-taminate the cleaned areas during the cleaning
Wipers used in ISO Class 3-5 cleanrooms are
typically a knit polyester wiper with edges that
are most likely sealed but may be cut if the durability process allows it. Wipers used in ISO Class
5-8 are typically a nonwoven polyester/cellulose
Previously, the contamination characteristics
were described as affecting the wiper selection
process. The performance characteristics, like the
sorption capacity or rate, also impact the wiper
selection decision. The sorption capacity of the
wiper is the amount of liquid the wiper can hold.
Auditors have requested test data to confirm that wipers used by a cleanroom
consumables distributor are non-linting. Is this a requirement of USP 797?
Fig. 1: Quarter-fold wiper.