Building Drainage Systems and COVID19

In the good old days the topic was called Public Health, nowadays its called Plumbing and Drainage. It is essential for all buildings to have properly designed, installed and maintained sewerage systems to prevent infecting occupants, whether it is 2003 SARS, 2020 COVID19, or Influenza.

youtube is unreliable here is the link: https://www.youtube.com/watch?v=Uv38qdl4Z1M

Recently, when COVID19 infection was discovered spreading within Hong Mei House, Tsing Yi on 10 and 11 February 2020, the RTHK report stated that the HK Government instantly reported it was not a “U trap” problem [RTHK link] a reference to the SARS outbreak in 2003 where the disease spread through the drainage system in block E Amoy Gardens infecting occupants, and requiring evacuation of the block.

youtube is unreliable at the moment, here is the link https://www.youtube.com/watch?v=GTNvTuV_CM4

I predicted the cause would be the sewer vent pipe, vent pipes are part of the high rise drainage system designed to prevent loss of the water seal in U traps. Subsequently, my suspicion was confirmed, the SMCP newspaper confirmed that the vent piping inside the bathroom was damaged (see SCMP photo below). Therefore, droplets could contaminate the bathroom area.

CREDIT: SCMP Government Press Conference Handout — BROKEN VENT pipe

Still problems in 2020

The photo below taken 15 March 2020 shows damaged drainage system vent piping.

ABOVE: faulty drainage system spreads disease taken 15 March 2020

That drainage system is damaged, it is no longer an enclosed system, allowing odour, bacteria, virus to escape into the air.

We have always known that sewerage and drainage systems are important, providing a conduit for bacteria and viruses, yet the severe lessons from SARS in 2003 and now from COVID19, demonstrate lessons still have not been learned!

Legionnaires Disease Outbreak Hong Kong update 15 Feb 2020 Cold Weather

There are countless poorly informed commentators that promulgate the myth that Legionnaires Disease is only warm-weather / summer time disease, it’s not, and never has been.

It’s winter in Hong Kong and we have an ongoing Legionnaires Disease Outbreak with patients admitted between 1 Feb. 2020 – 14 Feb. 2020 so far.

Lets assuming ten (10) day incubation period, what was the weather during that period of time? The Hong Kong Observatory records daily weather data, and the following minimum and maximum air temperatures were in recorded at Kwun Tong, the nearest weather station to the outbreak:

  • 22 Jan 2020 between 16.9 C and 24.4 deg C
  • 23 Jan 2020 between 19.8 C and 25.5 deg C
  • 24 Jan 2020 between 18.4 C and 22.6 deg C
  • 25 Jan 2020 between 17.9 C and 21.9 deg C
  • 26 Jan 2020 between 12.2 C and 20.1 deg C
  • 27 Jan 2020 between 9.8 C and 16.9 deg C
  • 28 Jan 2020 between 9.9 C and 16.4 deg C
  • 29 Jan 2020 between 10.1 C and 17.9 deg C
  • 30 Jan 2020 between 10.3 C and 17.6 deg C
  • 31 Jan 2020 between 11.7 C and 17.8 deg C
  • 1 Feb 2020 between 13.4 and 17.7 deg C
  • 2 Feb 2020 between 15.0 and 17.7 deg C

The HKO data shows the typical range of wintertime temperatures experienced during the cold weather season in Hong Kong.

In conclusion, the evidence demonstrates that during cold weather Legionnaires Disease outbreaks do occur, contrary to literature this disease is NOT limited to warmer climate conditions, and during the winter Legionnaires Disease cases, clusters, and outbreaks may occur.

HKO cold weather warning symbol

#legionella #outbreak #winter #legionnaires #disease #hongong

COVID19 and Buildings – Tsing Yi

UPDATE

14 March 2020 – Another similar incident is reported at Heng Tai House, Fu Heng Estate, Tai Po [link]


RTHK reports [link] some apartments in Hong Mei House, a residential tower block located in Tsing Yi, Hong Kong have been evacuated overnight after another person was diagnosed with the novel coronavirus (covid19) living in the same building, 10 stories directly below a person already diagnosed with the infection.

And fearing a repeat of the SARS in Amoy Gardens Block E, the HKSAR Government swiftly reported that the drainage U traps are in “good condition”.

Notwithstanding, the condition of the U trap, not every building (see photo below) has U trap fitted.

In addition, we must also consider faulty vent pipes (refer to our photo below). Vent pipes are connected in parallel to the main sewer system, well they should be, therefore any broken, damaged or disconnected piping provides an equally risky conduit for droplets and pathogens to spread into homes.

As shown in this video clip below, if the bathroom is negatively pressurised, pathogens can be dragged into the bathroom contaminating surfaces, risky infection of the occupants.

#coronavirus #hongkong #2019nCOV #airbourne #kelcroft #novelcoronavirus #SARS #drainage

Novel Coronavirus and SARS

A novel coronavirus emerged from Wuhan City, China in December 2019 (2019-nCOV) and it is apparent that it shares many similarities with the 2003 SARS outbreak, the virus is transported inside water droplets (aerosols) from coughing and sneezing in the air and its also shed in fecal matter which in turn is aerosolized risking contamination of surfaces.

History ignored is destained to be repeated, the same engineering issues remain today creating panic in the Hong Kong community.

Back in 2003, Kelcroft’s John Herbert was one of the few engineers that dared to visit buildings during the SARS outbreak, to highlight buildings requiring urgent improvements. You might not worry about a disconnected vent pipe, until you understand that’s a transmission path for the virus into your home.

Like SARS, and Legionella (which is bacteria) the novel coronavirus can be transported in the air, it’s said to be airborne pathogen, protected inside a water droplet, and depending on the air temperature and humidity, it is thought to be able to carry its virus package over long distances, outside and inside home.

And with favourable environmental conditions, the virus remains viable for up to 5 days on hard surfaces. ( link to useful Singaporean government list of household disinfection products).

If you are interested, here is a link to download our free SARS 2003 report: http://www.kelcroft.com.hk/download/kelcroft-sars-report-may-2003.pdf

#sars #coronavirus #hongkong #2019-nCOV #airbourne #kelcroft #2003

Pressurisation and IAQ

Positive building pressurisation and proper filtering of the outdoor air will be more important as testing reveals plastic in the air we breathe!

Plastic particles have been found in the air in the mountains but now in cities[1] . It may take years for the human studies and research but commonsense dictates plastic inside the human body, particularly in the lung should be minimised now.

1 https://www.theguardian.com/environment/2019/dec/27/revealed-microplastic-pollution-is-raining-down-on-city-dwellers

How to avoid mould in air conditioned buildings

moisture mould problems air conditioned buildings

In air conditioned buildings, the exterior vapour pressure will be higher than the vapour pressure in the air conditioned room, therefore the vapour and moisture flow is high to low (blue line in the diagram above)

Now normally this is not an issue, because a decent ventilation system will transport moisture back to the air conditioning cooling coil, it’s condensed, and safely drained away.

However, problems occur when a vapour retarder is installed (red line in above diagram) interrupting the flow. Moisture becomes trapped, and even the best ventilation system cannot transport it to the cooling coil. Instead what happens, damp, moisture, and then mould growth occurs (left of red line in diagram above).

wall-mould-800w-2

And we already know the problems associated with mould, it causes poor indoor air quality, and therefore health issues for the occupants. If the air conditioning room also happens to be under negative (relatively) pressure, as often occurs in hotel rooms, the situation is compounded because the vapour quantity is increased, accelerating the process. It should be taught in school “don’t ever use vinyl wallpaper in air conditioned buildings” because it causes mould.’

This phenomenon is not limited to Hong Kong, it occurs in hot tropical climates, whether you are in Singapore, Indonesia, Shanghai, or Hong Kong.

Furthermore, it’s the type of problem that’s not immediately apparent, mould doesn’t just appear overnight, and it is unlikely to surface within the defects liability period (DLP).

thermal-scan-101

So it is obvious, lining the external wall of an air conditioned space with any vapour retarder must be avoided at all costs. But sadly it still happens today, increasing maintenance and costs for building owners and operators.

About Kelcroft

Kelcroft based in Hong Kong provides specialist advice, including energy, built environment, and green building consulting services, advising owners and design teams, to lower the cost of building operations.

tags

#mould #mold #hongkong #buildings #hotels #maintenance

EMSD Cooling Tower Audit

emsd cooling tower audit, hong kong

In Hong Kong EMSD (www.emsd.gov.hk) requires an independent audit of cooling tower system every year, and still in 2016 it is needed. In the photo above the cooling tower basin is contaminated with dirty, and algae grow has started.

emsd cooling tower audit

Model air conditioning condenser side water schematic  credit: Prevention of Legionnaires’ Disease Code of Practice

The EMSD Code of Practice part 2 is the standard to assess the cooling tower system operation, and the annually conducted audit requires document review of the procedures and a physical inspection of the towers inside and out, then adjudicate compliance.

cooling tower audit hong kong

cooling-tower-hongkong-600w

Cooling Tower FAQ

Q. Who can conduct EMSD cooling tower audit in Hong Kong?
A. Kelcroft conducts independent EMSD cooling tower audit for Government, and private sector organsations.

Q. Is on-site checking of the cooling tower system required?
A. Yes, site inspection of the cooling tower system and operating records is required.

Q. What cooling tower system records will be checked?
A. The cooling tower operation check include the records for maintenance, water treatment, and laboratory results shall be reviewed.

Q. When is EMSD Cooling tower audit required?
A. Annually and after any major renovation work is recommended.

Q. What standard is used for the cooling tower audit?
A. The cooling tower audit standard is the latest version of EMSD Code of Practice for Water Cooled Air Conditioning Systems Part 2: Operation and Maintenance of Cooling Towers [link]

CLICK HERE for information about Kelcroft’s EMSD cooling tower inspection

BEEO compliance for new construction by John A. Herbert

by John A. Herbert

emsd cocr stage 1

How to comply with BEEO ordinance for new construction?

To build in Hong Kong you follow the traditional BD submission format, but you must also fulfil the mandatory requirements detailed in the Building Energy Efficiency Code (BEEO). How does that impact the construction process?

The building owner must engage an EMSD Registered Energy Assessor (REA) to complete and issue EMSD Form EE1, also known as Stage 1 Certificate of Compliance Registration (COCR), and an EMSD Form EE2, known as Stage 2 COCR.

When does the COCR need to be issued?

Stage 1 COCR must be submitted within two months after obtaining BD consent. For Stage 2 COCR, that must be submitted within four months after obtaining BD Occupation permit.

further details are provided on the EMSD website.

hongkong-emsd-energy-code-2015-rev-a

John A. Herbert attended Eco Expo Asia 2015

Kelcroft’s director Mr John A. Herbert, attended the annual Eco Expo Asia 2015.

BEAM award for Mr John A. Herbert – Sept 2015

John A. Herbert John A. Herbert