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10 November 2007

Some Clean Air Ideas for HK Email 3 Plan C


Office of the Chief Executive
Hong Kong Special Administrative Region
People's Republic of China

5/F, Central Government Offices, Main Wing,
Lower Albert Road,
Hong Kong
Telephone : (852) 2878 3300
Fax : (852) 2509 0577
E-mail :

Dear Mr Donald Tsang,

1. I have previously emailed you on 18 Jun 05 on my idea of Govt By Referendum [attached].

2. I have also emailed you on 12 Oct 07 on my idea of using jet engines to blow away the bad air from the worst polluted and most peopled parts of Hongkong. In this regard, I have had a short exchange of emails with someone in the Air Science Group but he did not consider the idea "workable" [attached].

3. I have also emailed you on 23 Oct 07 on Plan B which also aims to clear the air over Hongkong. It is an alternative to Plan A or it can be used together with Plan A for even greater effect. Plan B tries to dissolve most of dissolvable air pollutants such as Sulphur Dioxide [SO2], Ozone [O3], etc; and possibly convert dangerous Carbon Monoxide [CO] into its very safe cousin Carbon Dioxide through the simple expedient of adding some household bleach containing Hydrogen Peroxide [H2O2] into the tanks. Some of the Respirable Suspended Particles such as Lead will also be removed by bubbling the bad air through water and these can be further removed completely if the Emerging Air is FILTERED after passing through the tank. That same someone also considers this Plan B idea "unworkable".

4. Today, I would like to interest you in my Plan C, which can be deployed by itself or in addition to Plan A or Plan B -- or both -- for even greater effect.

5. Plan C is based on the fact that as I am writing this, Central/Western, Eastern, Kwai Chung, Kwun Tong, Sha Tin, Sham Shui Po, Tai Po, Tap Mun, Tsuen Wan, Tung Chung and Yuen Long [as at 12 noon just past], are all showing HIGH readings of the Air Pollution Index, except Kwai Chung which is MEDIUM. All are due to high readings of Respirable Suspended Particles except the Medium Kwai Chung which shows Nitrogen Dioxide.

6. Your Roadside Stations monitoring air pollution shows even higher [as usual the Roadside air is much dirtier than at the main monitoring stations] air pollution index readings, with Causeway Bay at 69, Central at 60 and Mongkok at 87. The first 2 are due to Respirable Suspended Particles while Mongkok is due to Nitrogen Dioxide.

7. Taking the past 24 hours at the 3 Roadside Stations, which probably strongly reflect the vehicular exhaust pollution, from 1300 hours yesterday to 12 noon today, Causeway Bay 'started' at about 75 and declined only slightly in 24 hours; Central 'started' at about 70 and declined a bit thereafter, while Mong Kok 'started' at 100 and declined a bit in 24 hours.

8. Thus, my Plan C targets vehicular exhaust pollution. First of all, should we be concerned about vehicular pollution? After all, most of us don't spend much time on the streets. We spend most times indoors, in offices or at home, where the air is better. I would venture that people DO spend more time at street level than they realise. For example, if you commute by bus, you would spend some time at a bus stop waiting for a bus. Then, even after you board the bus, you continue your bus trip AT STREET LEVEL, breathing in street level air. If your bus trip is 30 minutes x 2 every day, that is 1 whole hour breathing in street level air. Even the underground MTR stations where you wait may also be quite polluted. Has anyone taken air pollution readings in underground MTR stations? It may be quite high, too, given that the air would move down into the stations as well.

9. Thus, if the 3 Roadside Stations are any guide, street level pollution hovers around 75 almost round the clock, that is, 24/7/365. Since your expert has rejected my Water Tank idea to dissolve some of the bad air, my Plan C will try a mechanical method to reduce some of the vehicular exhaust pollution.

10. For this Plan C, I note that every vehicle has a tailpipe producing exhaust and that this tailpipe is low slung, beneath and behind the vehicle, and that the vehicle travels along roads mostly guided by white lane markings on the road. This means that the exhaust-producing tailpipe is only half a metre or so above the road and most of the exhaust smoke would emerge from the tailpipe and spread along the road almost exactly between the white lane markings painted on the road.

11. So, if we could spray a kind of glue on the busiest roads between the white lane markings, we could 'stick' away some of the lead and other particles produced from the tailpipe, as well as some of the chemical pollutants, too. It would be much more effective if we could fix a cheap and simple Deflector to the end of the tailpipe to deflect the exhaust smoke DOWN on to the sticky road. This would stick away a good percentage of the bad air particles and chemicals from the exhaust.

12. That's the basic idea. Now for some details. The glue should be longlasting, say, should remain sticky for weeks so that respraying need only be done once a fortnight or once a month, or so. It should remain sticky even after rains or strong sunshine. It should have the ability to stick most of the harmful particles from tailpipe exhaust. It should be easily sprayed from a special van modified for this purpose. The van would have a small tank containing the watery glue and a sprayer at its back operated by a small pump in the van. The van should be able to spray an effective layer of glue onto the road even when moving at fairly high speeds of say, 50 kmph so it won't hold up vehicles behind during its spraying. [Of course, it could spray at night, when there is far less traffic].

13. The sprayer should be able to spray at a single pass, the entire lane of the road, that is, between the 2 white lines marking the lane. Then do the other lane/s. You will need a small fleet of such vans. But then, you only need to spray the busiest and most polluted roads, not the entire Hongkong.

14. The glue will remain intact between the white lane markings. But nearer the white lane markings, the vehicles' tyres will run over the glue and probably remove much of it. This is not a problem because the tailpipes are slung well between the rear tyres, some cars more to the left and some more to the right, but both quite near the centre of the car. So there will be enough glue on the central parts of the road lane to stick the particles from the exhaust. Of course, the glue should not lead vehicles to skid or corrode the rubber tyres, which are highly unlikely. It's just glue.

15. I have mentioned the Deflector in Paragraph 11. The Deflector should not be 90 degrees straight down because this may cause some exhaust air to 'back up' into the catalytic converter, which most cars now have. It should be about 135 degrees obtuse angle measured from the catalytic converter so that the Deflector points about 45 degrees down and rear-wards. This will ensure a downward flow of exhaust towards the glue-road yet not block or reduce the speed of airflow from the catalytic converter. Experiments should be done to determine which obtuse angle is best to serve both purposes.

16. If this project goes ahead, the Deflector can be produced very quickly for about HK$10-20 each and fitted at all petrol stations when the vehicles come in for petrol top up. It can be plastic or metal. I have in mind the simple aluminium tightener that grips the rubber hose onto the tap by the simple means of turning a simple thumb screw. There are many ways to secure a Deflector onto the end of the tailpipe and it would take less than a minute to fit 1. It can be fitted when the driver is topping up his petrol tank.

17. How to proceed from here? I don't recommend getting a Spray Van yet. We should test the Concept. Which is that 'Glue on the road can stick most of the exhaust chemicals and particles produced in vehicle exhaust and thereby remove these from the air we breathe'.

18. To begin, find a flat material that best approximates the road surface. It could be a rough plastic sheet, strong paper, spongey layer, cardboard, cloth, cotton, metal plate like a thin sheet of aluminium, etc. Then coat this flat piece with glue of the kind of glue you will likely use. Then place this flat piece, glued-side uppermost, on a busy road for a period of time. Then retrieve it back into the lab and measure very accurately the amount of air pollutants stuck on the piece, both the chemicals like Sulphur Dioxide and the particles like Lead. [The glue may stick BOTH chemicals and particles]. The more chemicals and particles stuck on the piece the better because it will mean LESS chemicals and particles in the air to be breathed in.

19. To save time, do this with many pieces each time. After you have some indication of success, that the Concept works, then do the experiments with vehicles fitted with Deflectors. This will indicate how many more times the Deflector is more effective than a straight tailpipe.

20. Then, it will be time to conduct a large experiment near 1 of the 3 Roadside Stations. Persuade or force all the vehicles, by police road blocks if necessary, to fit a Deflector before allowing them to proceed near the Road Station experiment roads -- both directions of traffic flow -- and spray the roads near the Roadside Station, manually if necessary, and see how much reduction you get in pollution readings. If successful, then implement it country-wide with a fleet of Spray Vans and enforced fitting of Deflectors on every vehicle.

21. To end, I understand that emails are often considered as official communication and many emailers are therefore very cautious what they write in an email. I here append my Windows Live Messenger [an Instant Messenger] chat address so that anyone wanting to chat very casually can type a chat back and forth with me, that is, when we are both online at the same time. The nature of email has become quite official but Instant Messenger chats remain very informal because you can only type about 50 words in each paragraph before you must send it, so it is all very informal. So, IM me for a chat if you want a quick and casual chat. My Windows Live Messenger address is

For Clear Air and Clear Minds,
I am,

Robert HO
28 Bukit Batok Street 52
#20-03 Guilin View
Singapore 659248
Tel: [+65] 68989553
HP: [+65] 90127417
29 Oct 07 1520