Glossary

Health building notes(HBN) give best practice guidance on the design and planning of new healthcare buildings and on the adaptation or extension of existing facilities. They provide information to support the briefing and design processes for individual projects in the NHS building programme.

https://www.england.nhs.uk/estates/health-building-notes

An  high efficiency particulate air(HEPA) filter, also known as a high efficiency particulate arresting filter, is an efficiency standard of air filters.

Filters meeting the HEPA standard must satisfy certain levels of efficiency.
 Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% of particles whose diameter is equal to 0.3 μm, with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm. 

As a example HEPA filters capture pollen, dirt, dust, moisture, bacteria (0.2–2.0 μm), viruses (0.02–0.3 μm), and submicron liquid aerosol (0.02–0.5 μm).

Hospital Sterile Services Department(HSSD), also known as Sterile Services Departments (SSDs) or Central Sterile Services Department(CSSD) are responsible for ensuring that reusable medical devices, such as instruments, endoscopes, and equipment, are cleaned, sterilised, and repackaged to high standards, ready for reuse in operating theatres and other healthcare areas.

Health Technical Memoranda (HTMs) give comprehensive advice and guidance on the design, installation and operation of specialised building and engineering technology used in the delivery of healthcare.

https://www.england.nhs.uk/estates/health-technical-memoranda/

Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality.