Dear Environmental Protection Department,

Under the Code on Access to Information, I am writing to request access to existing records held by the Environmental Protection Department concerning the measurement methods and related technical requirements adopted under the Indoor Air Quality (IAQ) Certification Scheme for Offices and Public Places. This request seeks only non-personal technical and policy documents, and is distinct from any previous requests relating to the certified premises register, statistical data on IAQ parameters, certificate renewal or attrition, complaints, ventilation regulation, or scheme effectiveness evaluations.
1. Official measurement and sampling methods for core parameters
Please provide the current (and, if revised within the past five years, the previous) prescribed or recognised measurement methods, sampling procedures and analytical standards for the following parameters under the Scheme:
• Carbon dioxide (CO₂)
• Respirable suspended particulates (RSP / PM10)
• Fine suspended particulates (FSP / PM2.5)
• Total volatile organic compounds (TVOC)
• Carbon monoxide (CO)
• Airborne bacteria count
• Any other parameters required to be tested under the Scheme
Please include specific requirements regarding sampling duration, principles for selecting sampling locations, sampling flow rates, and instrument specifications.
2. Reference standards and guidance documents
Please provide the technical guidance, method reference documents or standards on which the Scheme relies (for example, relevant sections of the Guidance Notes for the Management of Indoor Air Quality in Offices and Public Places, international standards such as ISO, ASTM, NIOSH or EPA methods, or other recognised methods), together with the version numbers and effective dates of these documents.
3. Technical requirements for Certificate Issuing Bodies (CIBs)
Please provide the quality assurance / quality control (QA/QC) requirements that Accredited Certificate Issuing Bodies must follow when conducting measurements, including requirements relating to instrument calibration, blank samples, replicate measurements, and laboratory accreditation.
4. Records of method revisions
Please provide records of any revisions to the measurement methods or sampling requirements under the Scheme over the past ten years, including the reasons for revision, effective dates, and a summary of the key changes.
I am seeking only existing non-personal technical and policy documents. Where the records are held in electronic format, please provide them in searchable PDF, Word, or other machine-readable formats. If any part of this request is refused, please specify the exemption relied upon, the scope of the withheld material, and the reason for refusal.
Thank you for your assistance.

Yours faithfully,
Gabriel PAN YIFU