Mat Protocol for Cleanroom Use
utilization of multi-layer adhesive mats for cleanrooms is almost
universal. However, how the mats are used is unique to each
cleanroom. Mats can vary in size, color, number, and placement based
on the logistics and characteristics of each individual
should be placed in an area where they will be on clean, hard
flooring. They should be placed just before or just after the
ingress/egress point for each cleanliness or control change. It is
suggested that the placement sites are worked backward from the final
clean area or cleanroom.
• cleanroom - gowning area
cleanroom - staging area
• gowning area - control area
control area - common hallway
hallway - warehouse or receiving
• common hallway - public
Matting should be placed so that all those passing
through that point must step on the mats. Matting should be placed
with the longer dimension of the mat in the same direction as the
traffic flow for maximum footfalls on each mat. The minimum number of
footfalls should be two with each foot for each location.
proper size mat for each area of placement depends on the width of
the opening and the variance and direction of the traffic. Normally
the width of the mat should be 2/3rds to 3/4ths of the width of the
doorway. It does not normally need to cover the full width because
ordinary traffic passes through the middle of the doorway and not
along the edge. However, if the traffic enters at a sharp angle or
from the side of the entryway, then the width of the mat needs to be
wider than the doorway to allow for enough footfalls.
stated above, the length of the mat should be long enough to provide
at least two footfalls with each foot at each location. Usually this
is a minimum of 45 inches.
color of the mats, which has no effect on the function of the mat,
can vary from standard blue, white, and grey to custom colors and
printed messages. In general, white shows the most dirt and
particulates, and is normally preferred to make sure the layers are
changed at frequent enough intervals. However, grey and blue work
just as well when a maintenance schedule is set.
often the layers should be removed depends on a number of factors:
How dirty the area the personnel are coming from is.
number of people or pairs of feet per shift or per hour.
difference in cleanliness between the areas.
• The size of the
mats and how many mats or locations are in the series.
general, areas farther away from the cleanroom will be dirtier.
Changing the layers at this point of use every half hour would be a
benchmark with which to start. The final entry area into the
cleanroom is probably from a clean area to a very clean area and each
layer may last 4 to 8 hours.
However, this is just a rough
guideline and each point of use will vary greatly. A few days of use
and observation will help to determine the optimal mat layer change
placing a new mat down or replacing an existing mat, thoroughly
clean the surface to remove contamination that may act as a barrier
and keep the mat from properly adhering to the floor. Make sure to
remove any adhesive residue if you are replacing an existing mat.
It is recommended to use a pre-saturated wiper that contains a
percentage of isopropyl alcohol. Make sure the surface is completely
dry before application.
apply the mat, remove half of the release liner in the long
direction of the mat, which will help with the alignment of the mat.
you have the mat properly aligned in the location you want, start
smoothing out the half of the mat with the adhesive exposed. Start
at one end and work toward the middle making sure you do not trap
air under the mat as you go, then remove the rest of the release
liner and smooth the rest of the mat out in the same direction in
which you removed the release liner.
should be stored flat and for several hours in similar climate
conditions as the point of use. For ideal results, the mats should be
used in a controlled environment setting but may be placed in any
area that has a temperature of 54-95 F (12-35 C).
storage of mats should always be on a flat and hard surface. Storage
on the original shipping pallet is recommended. Normal warehouse
conditions are usually acceptable but extreme temperatures (less than
32 or greater than 105 F / 0 or 40 C) should be avoided.
of mats longer than one year from the date of purchase is not
recommended. However, under normal storage conditions, matting should
not have any variation in performance for a period of up to three