L Fine®P

August 18, 2021
Nipro CorporationN

Notice of Results of Human Coronavirus (OC43) Inactivation
Performance Test by Humidification Using Ionless™
Hypochlorous Acid Water CL Fine®
Nipro Corporation (Headquarters: Kita-ku, Osaka, Japan; President & Representative Director: Yoshihiko Sano;
hereafter, “Nipro”) hereby announces that the test results demonstrated that the Ionless™ hypochlorous acid water
CL Fine® (hereinafter CL Fine®) reduced the beta coronavirus (OC43),* which is the same type as the novelcoronavirus (SARS-CoV-2), to the detection limit (99.78%) when the space where the viruses were floating was
humidified with CL Fine® so that the effective chlorine concentration was approximately 0.02 ppm.
As stated in the press release dated January 29, 2021,* CL Fine® is slightly acidic electrolyzed water prepared byremoving impurity ions from hypochlorous acid water (conforming to JIS B8701: 2017) using our uniqueelectrolysis and purification technologies. In addition to the results of the reduction of coliphage MS2, a type ofvirus, and Staphylococcus aureus, a type of bacterium, which were revealed in the spatial spray test of CL Fine®
conducted by a third-party organization, we have also confirmed the results of reduction of the novel coronavirus(SARS-CoV-2) by suspension test using CL Fine®.
We recently observed the environmental bacteria in the space of indoor swimming pools* and found that there
were fewer environmental bacteria compared to the general environment (Table 1). We also found that theeffective spatial chlorine concentration of indoor swimming pools was 0.02 to 0.03 ppm (Table 2). Pool water isslightly alkaline (around pH8) and becomes weakly acidic (pH6 to 7) when spontaneously evaporated (Table 3). It
can be inferred that this is the result of the spontaneous evaporation of sodium hypochlorite in water (1 ppm orless) with sodium ions remained in the water. Since the total amount of ions of CL Fine®, including sodium ions,is less than one tenth of the average amount of tap water, the total ion concentration when CL Fine® is humidified,is considered to be close to that of the aerial component of indoor swimming pools.
As a result of reproducing the effective spatial chlorine concentration of indoor swimming pools (0.02 to 0.03ppm) in the general environment by humidifying the space using CL Fine®, we succeeded in creating a clean
space by reducing the airborne bacteria / viruses and adhered bacteria / viruses (Figure 1).
(1) When the chlorine concentration in the space was 0.02 ppm, human coronavirus (OC43) decreased by
99.78% or more in 60 minutes.
(2) When the chlorine concentration in the space was 0.02 ppm, Staphylococcus aureus decreased by 99% ormore in 60 minutes.
(3) When the chlorine concentration in the space was 0.02 ppm, Staphylococcus aureus on and under the tabledecreased by 99% or more in 4 hours.

In addition, as announced in the press release dated January 29, 2021, a decrease in the novel coronavirus(SARS-CoV-2) and influenza virus type A (H1N1) was confirmed by suspension test using CL Fine® (Table 4).
Based on these results, we believe that CL Fine® can also be used as an infection control agent.
When using tap water for humidification, it is necessary to consider the risk of contamination by Legionella spp.
and bacterial infectious diseases, and pay sufficient attention to daily water exchange and hygiene management in
the humidifier. On the other hand, it has been confirmed that CL Fine® can disinfect Legionella spp. by 99.9% ormore when the effective chlorine concentration is 1 ppm or more (Table 5). In addition, when using humidifiers
that were not protected against bacterial growth, bacterial growth was observed in tap water even if they werereplaced daily, but no bacterial growth was observed in CL Fine® even if they were not replaced (Table 6). This
indicates that the risk of bacterial infections caused by Legionella spp. by humidifying the space using CL Fine® isextremely low.
Nipro will continue to conduct further studies and provide CL Fine® in order to help prevent the spread ofvarious infectious diseases.
(Table 1) Environmental bacteria in general environments and indoor swimming pools(Table 2) Effective spatial chlorine concentration of indoor swimming pools
FacilityIndoor
swimming pools(3 facilities)

Environmental conditions
WaterRoomtemperaturetemperature
30°C

30 to 31°C

Effective spatial chlorine concentration (ppm)Theoretical
Actual measurement valuevalue(n = 4, Mean ± SD)
0.026 to 0.028

0.028 ± 0.004 to 0.030 ± 0.004

(Table 3) Comparison of pH between humidifier mist and spontaneous evaporation
SampleCompoundIndoor swimming poolwater (2 facilities)(Sodium hypochlorite)
Hypochlorous acid
Sodium hypochlorite

pH value of collected sample

Concentration

pH

Humidifier mist

Spontaneousevaporation

0.2 to 0.3 ppm

7.99 to 8.16--1 ppm
1 ppm

6.12
7.69

5.88 ± 0.02
7.42 ± 0.05

6.03
6.01

(Figure 1) Inactivation test on Staphylococcus aureus and human coronavirus (HCoV-OC43) by humidification
Airborne virus:
Airborne bacteria:
Adhered bacteria:
human coronavirus
Staphylococcus aureus
Staphylococcus aureus

LOD: limit of detection®

*: CL Fine / purified water was sprayed into the space where bacteria / viruses are floating / adhering.

(Table 4) In vitro virus sterilization performance test
Bacteria / virus
Novel coronavirus(SARS-CoV-2)
Influenza virus type A (H1N1)

20 seconds

Duration of action
1 minute
5 minutes

30 minutes≥0.3 ppm≥0.3 ppm≥0.3 ppm≥0.3 ppm≥1 ppm≥0.3 ppm≥0.3 ppm≥0.3 ppm

Hypochlorous acid (HOCl) concentration where reduction of 3 log or more viruses (= reduction rate: 99.9% or higher) was observed(Table 5) Sterilization performance test against Legionella spp.
Test substance
CL Fine®
Tap water

Effective chlorine concentration

Disinfection rate of Legionella spp. (%)

10 ppm1 ppm
0.1 ppm(0.16 ppm)

>99.9
>99.9
89.1
3.8

Mixing ratio of the bacterial solution and test substance: 1:98, mixing time: 5 min

(Table 6) Bacterial growth in humidifiers

Humidified for 7days (1 hour / day)®

Sales of Ionless™ Hypochlorous Acid Water “CL Fine ”
Sales area: nationwide
Sales target: health institutions, nursing care facilities, pharmacies, etc.
Reference price (excluding tax): 20,000 yen (10 liters)
Category: Miscellaneous *This product is not a medical product.
Ingredients: Hypochlorous acid (40 ± 10 ppm), sodium chloride (10 mg/L or less)Nipro will continue to strive to develop and provide products that not only improve the quality of life (QOL) ofpatients but also are safer and meet the needs of society.
*Human coronavirus (HCoV-OC43):
One of four common cold viruses (HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1) that spreadamong humans.
*Environmental bacteria:
Bacteria that live in the natural environment.
*CL Fine® is a trademark of Nipro Corporation.