Dear Dillion,

Please be informed that your application for access to information was
received by this Department with case ref. no. AIO/6/5/40 2026.
In response to the request, we are following up and will reply as soon as
possible.

Regards,
(CH LAM)  
for Director of Electrical and Mechanical Services

寄件者:         "Dillion20" <[ATI #1687 email]>
收件者:         "ATI requests at Electrical and Mechanical Services
Department" <[Electrical and Mechanical Services Department request email]>
日期:         14/10/2026 21:01
主旨:         [External Email] Access to Information request - Under the
Code on Access to Information, writing to request access to existing,
non-personal data from(EMSD)
寄件者:         [ATI #1687 email]

══════════════════════════════════════════════════════════════════════════

To: Access to Information Officer,
Department: Electrical and Mechanical Services Department(EMSD)

Under the Code on Access to Information, I am writing to request access to
existing, non-personal, aggregated public administration records held by
the Electrical and Mechanical Services Department (EMSD) relating to
indoor air quality (IAQ) and the performance of mechanical ventilation and
air-conditioning (MVAC) systems in government premises or other facilities
to which the Department has provided technical support.
I would be grateful if the Department could provide any of the following
existing records:

1.IAQ Monitoring & Sampling Summary Statistics
Request: Aggregated, anonymized summary statistics (preferably for
2023–2025, or up to the latest available period) of indoor air quality
(IAQ) sample checks and monitoring conducted, commissioned, or
audit-reviewed in MTR train compartments and underground/enclosed
stations, pursuant to the EPD’s Practice Note for Managing Air Quality in
Air-conditioned Public Transport Facilities – Railways.
Parameters requested:Carbon Dioxide () 、Respirable Suspended Particulates
() and Fine Suspended Particulates ()、Total Volatile Organic Compounds
(TVOCs) and Nitrogen Dioxide ()、Airborne bacteria count
Data breakdown: For each parameter, please provide the total number of
readings/samples, the mean / median / 95th percentile (where available),
and the count/percentage of readings meeting or exceeding the relevant
reference levels (Level 1 and Level 2 guidelines).

2. Breakdown of Railway Premises and Rolling Stock Covered
Request: A summarized list or breakdown of the types of railway premises
and rolling stock involved in the IAQ monitoring scheme (e.g., underground
station concourses/platforms, elevated/at-grade stations, major
interchange hubs, and different generations/models of train fleets),
without any personal data or security-sensitive specifics.

3. Mechanical Ventilation & Air-Conditioning (MVAC) Technical Guidance &
Audit Records
Request: Published or internally compiled summaries of technical advice,
regulatory audit findings, or operational standards maintained or issued
regarding the design, operation, and maintenance of MVAC systems in MTR
facilities. This includes standards for air filter cleaning/replacement
schedules, ductwork inspection, and fresh air intake controls.

4. Operational Protocols During Peak Hours & High Passenger Load
Conditions
Request: Existing operational guidelines, technical parameters, or summary
protocols concerning MVAC system adjustments (such as fresh air injection
rates, ventilation boosting, or air purification procedures) during peak
patronage hours or periods of high passenger density when  or particulate
concentrations tend to surge.

This request seeks only existing, non-personal, aggregated records and
does not include any personal data. I am not requesting the Department to
create new analysis; if any item is not held, please indicate so and
provide the closest existing record instead. If the exact format is
unavailable, compiled tables, annual report extracts, or spreadsheet
exports would be acceptable.

Please confirm receipt of this request and advise on the expected handling
timeframe. If any information is to be withheld, please identify the item
and the reason under the Code. Replies may be sent to the contact details
below.

Thank you very much for your time and resistance

Your faithfully,

Dillion

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