QED Disinfection of Future Public Transportation in Hong Kong

PITTSBURGH - April 2, 2015 - PRLog -- Background
Today, infectious diseases including SARS and H1N1 continue to haunt Hong Kong. SARS stands for severe acute respiratory syndrome and H1N1 for human swine flu virus. Since 2003, SARS was identified [1] by the WHO as a corona virus never before seen in humans. SARS is spread [2] by droplets from sneezing and coughing, but may be transmitted by touching contaminated objects.In fact, infectious diseases are usually transmitted through the hands by touching public surfaces. The hands then pass the virus into our bodies upon rubbing our eyes, nose or mouth before washing our hands. In Hong Kong, over 2.5 million commuters use the public transit system every day, and can easily spread infectious viruses to each other by contacting handrails and grab poles commonly used to hold and avoid falling under abrupt train car and bus motions.

In this regard, the Hong Kong authority constantly reminds commuters through automated announcements to hold handrails and grab poles for their own safety, but avoiding touching them is almost impossible making the transmission of infectious viruses by contacting public surfaces a virtual certainty.

In 2006, handrails in Hong Kong trains were disinfected by applying a spray of NSTDC to public surfaces to avoid the transmission of infectious viruses. NSTDC stands for nano silver-titanium dioxide coating.  All escalator handrails, the buttons on ticket issuing machines and all handrails and buttons in elevators including grab poles in train cars and buses were coated.

More recently in 2010, an anti-microbial coating was developed [3] that is thought to set a new standard in the disinfection of infectious viruses. Transparent, colorless and odorless, this smart coating can sustain surface disinfection by simply spraying on public surfaces. Compared with other disinfecting coatings, the smart coating is effective for at least 30 days. Test results show the smart coating can kill 99.9% of bacteria within 1 minute and 99% of the H1N1 virus within 3 minutes. The effectiveness of the smart coating lasts significantly longer than the conventional disinfectants, many of which will lose their disinfection capability as they evaporate. On the other hand, laboratory tests showed smart coatings are indeed capable of long-term disinfection with 100% effectiveness even after 30 days. The smart coating is not permanent and can be removed by washing off with detergent-in-water solution.

Problems
Spraying NSTDC’s and smart coatings on existing handrails and grab poles is a reasonable solution to disinfection of infectious viruses while allowing commuters to avoid accidental falling in train cars and buses, but spray coatings are at best a temporary solution. Future public transport need not be so restricted by including alternative designs with permanent coatings. Permanent nano-coatings capable of providng a continuos supply of UV-C are desirable in future handrail and grab pole designs. Moreover, claims that sprayed coatings containing colloidal silver are non-toxic must be questioned as nano-silver that enters the body unequivocally damages the DNA and can cause cancer.  Alternative handrail and grab pole designs using permanent anti-microbial coatings emitting UV-C radiation are suggested.

Proposal
QED induced EM radiation emitted from the surfaces of handrails and grab poles produced from internal heaters is proposed to provide the UV-C from which infectious viruses on their surfaces may be disinfected.  QED stands for quantum electrodynamics, EM for electromagnetic, and UV-C for ultraviolet radiation at 254 nm. Similarly, handrails can be coated with UV-C emitting surfaces. During fabrication, the handrails and grab poles would be provided with a permanent 50-60 nm ZnO coating that can be periodically cleaned to minimize pathogen residue. The UV-C from a typical grab pole arrangement is illustrated in the thumbnail, but the electrical heaters inside the poles are not shown. The QED grab pole is similar to the recently proposed hand-held drinking bowl that uses body heat to disinfect water borne pathogens from water without electricity.  See http://www.prlog.org/12379390-nanotechnology-in-purifying...

Theory and Analysis
Handrails and grab poles in future public transit train cars and buses disinfect infectious viruses with UV-C radiation as the heat supplied to the inside of the handrail and poles is transferred to the surface ZnO nano-coating. Because of QM, the supplied heat cannot increase the temperature of the coating as its heat capacity vanishes under TIR confinement. QM stands for quantum mechanics and TIR for total internal reflection. Instead, the heat is conserved by QED inducing its conversion to QED induced EM radiation. See numerous QED applications at http://www.nanoqed.org

The TIR confinement only occurs as the heat supplied from the inside of the handrail and pole flows into the surface ZnO nano-coating. The TIR wavelength λ of the EM radiation is, λ = 2 n d, where, n and d are the refractive index and thickness of the coating. The ZnO coating having n = 2.4 only needs to have a higher refractive index than the pole material which is typically steel. Hence, QED induces the creation of EM radiation in the UV-C at λ = 254 nm in a coating having thickness d = 53 nm.

Conclusion
In future public transport, QED induced UV-C radiation from heated handrails and grab poles offers the Hong Kong government a direct and permanent solution for disinfecting infectious diseases in public transport train cars and buses. The nano-coatings of ZnO are permanently applied to the outside surface of the handrails and grab poles. Electrical heating must be provided inside the handrails and grab poles, but costs are minimal because of the low required power.

References

[1]  “SARS Virus”, WHO, April 16, 2003.
[2]  “SARS virus”, WHO, Reuters, April 25, 2003.
[3]  “HKUST Develops World’s First Smart Anti-microbial Coating to Control Infectious Diseases” See http://www.ust.hk/about-hkust/media-relations/press-releases/hkust-develops-worlds-first-smart-anti-microbial-coating-control-infectious-diseases/