Technical Standards for HEPA-filtered Ice Machines
The ISO Standard
ISO14644-1 is the universal standard for any environment
where the concentration of airborne particles is
controlled (1). In order to achieve a
classification, the tested environment must contain
fewer particles per cubic meter than the requirements
outline. Class 1 is the strictest environment,
allowing for the lowest particle concentration in the
air. Class 9 is the loosest class. The
cleanest of hospital cleanrooms are considered an ISO
Class 8 (2).
SAFE ICE provides ISO Class 7 environment inside an ice
machine, exceeding the level of the cleanest hospital
cleanrooms (see table below).
|
0.5µ particles/m^3 |
1.0µ particles/m^3 |
5.0µ particles/m^3 |
Sample Volume |
Safe Ice Sample #1 |
0.0 |
0.0 |
0.0 |
6.8 liters |
Safe Ice Sample #2 |
0.0 |
0.0 |
0.0 |
6.8 liters |
Safe Ice Sample #3 |
0.0 |
0.0 |
0.0 |
6.8 liters |
ISO-7 Requirement (1)* |
352,000.0 |
83,200.0 |
29,300.0 |
6.8 liters |
*ISO Class 7 does not define a maximum concentration of particles smaller than 0.5µ.
CDC Guidelines
for Environmental Infection Control in Health-Care
Facilities
The Guidelines for Environmental Infection Control in
Health-Care Facilities (3) published by the
Centers for Disease Control and Prevention (CDC)
properly recognizes the potential for microorganisms to
be present in ice and ice making machines. It
recommends cleaning of the ice machines on a regular
basis as defined by manufacturer recommendations.
However, the CDC guidelines failed to recognize the
potential for ice machines to become contaminated
through airborne sources, instead focusing on water
borne sources and the transferral of organisms from
hands. While the latter is a significant risk,
water borne contamination is less likely than airborne
contamination. This is because potable water sources
within healthcare facilities typically have water
filtering systems in place to prevent organic contamination.
SAFE ICE equipment exceeds the recommendations of the
CDC by virtually eliminating all airborne
contaminants. It is recommended that proper water
treatment and filtration is used in conjunction with
SAFE ICE in order to prevent the introduction of water
borne contaminants.
[1] International Organization for
Standardization. (1999). Cleanrooms and associated
controlled environments. ISO.
[2] University of Purdue. (2011, January 7).
www.purdue.edu. Retrieved from http://www.purdue.edu/newsroom/purduetoday/general/2011/story-print-deploy-layout_1_10197_10197.html
[3] www.cdc.gov/ncidod/hip/enviro/guide.htm
