AHU Upgrade and Fire Damper Repair in Chichester Science Centre: Case Study

Why a Chichester Science Centre Called on ARM Environments

The South Downs Planetarium and Science Centre is one of West Sussex's most distinctive educational venues, featuring a 96-seater domed space just off the Chichester Bypass, run by a dedicated team of volunteers and astronomy enthusiasts. Families visit to experience the dome's immersive projections of the night sky, making indoor air quality a genuine priority: this is an enclosed space, heavily occupied, with children as its primary audience.

In 2021, with COVID-19 having temporarily shut the centre down, the team took the opportunity to do something proactive. Rather than simply waiting to reopen, they contacted ARM Environments to assess and upgrade their air filtration and ventilation systems — a smart use of downtime that would make the dome a safer, healthier space for everyone returning to it.

If you're interested in upgrading your ventilation systems or getting your fire dampers checked, visit our services page.

Key challenges:

Large groups of families, including children, regularly occupying an enclosed dome
Poor outdoor air quality from the adjacent Chichester Bypass
Existing ventilation methods ineffective at removing microbial matter and airborne pollutants

What Our HVAC Investigation Found at the Chichester Site

The dome's ventilation system is genuinely unusual. Rather than conventional wall or ceiling vents, clean air is designed to enter through perforated metal panels lining the domed ceiling — the same panels onto which the night sky is projected. Floor grilles positioned beneath the seating extract VOCs rising from the carpet and keep CO₂ levels in check by pulling stale air downward and away from occupants.

On paper, it's a well-considered system. In practice, our preliminary tests found that air was barely circulating at all.

Investigating further, we identified the cause: a closed fire damper was blocking the airflow through the system entirely. Fire dampers are a critical safety component in any ventilated building, but when left in a closed position outside of a fire event, they become a complete barrier to the airflow that a ventilation system depends on. In this case, it meant the dome's carefully designed air distribution had been rendered ineffective — likely for some time.

Our AHU Upgrade Solution: Bipolar Ionisation

With COVID-19 still a live concern, the Science Centre's priority was an air purification approach that would actively neutralise bacteria and viruses — not just filter them. We addressed both problems identified in our investigation simultaneously.

First, we repaired the closed fire damper, restoring airflow through the system and allowing the dome's unique ventilation design to function as intended.

Second, we upgraded the site's air handling unit (AHU) with bipolar ionisation technology. Bipolar ionisation works by generating and releasing charged oxygen ions into the airstream. These ions actively target and break down airborne pollutants — including particulate matter, bacteria, virus cells, odorous gases, aerosols, and volatile organic compounds — rather than simply trapping them in a filter. For a venue alongside a busy bypass, this dual protection against both microbial and traffic-related air pollution made it the right fit for the site.

See our pollutants page for more information.

Results: Cleaner Air in an Unconventional Space

With the fire damper repaired and the AHU upgraded, the South Downs Planetarium and Science Centre now has an air quality system that is both functioning correctly and actively working to protect the people inside it.

For a venue where families arrive with young children expecting an immersive, enjoyable experience, that matters. Poor indoor air quality in an enclosed dome — one sitting next to a busy bypass — would be a persistent background risk that no amount of enthusiasm for astronomy could offset. The upgraded system mitigates both the traffic pollution infiltrating from outside and the microbial risks that come with high-density occupancy, keeping the centre COSHH compliant and its visitors safe.

It also demonstrates something worth noting: good indoor air quality doesn't require a conventional building. As Adam Taylor puts it — if clean air is achievable in a domed planetarium in Chichester, it's achievable anywhere.

"This venue is incredibly fascinating to work at on account of its unique structure. Contrary to how some spaces circulate air, this space has floor grilles under the chairs which help to extract VOCs from the carpet and keep pollutants, primarily CO2, to a minimum. The domed ceiling consists of perforated panels which let clean air through whilst also allowing for the night sky to be projected seamlessly onto the inside of the dome. It's a great demonstration of how we can introduce clean air into unconventional spaces via rather unique and novel methods — and it goes to show that if we can have clean air even within this tricky space, we can have clean air anywhere."

Adam Taylor, CEO, ARM Environments

Get Your HVAC Upgrade in Chichester

Looking to upgrade your air handling unit or improve indoor air quality in a commercial or public space? ARM Environments provides AHU upgrades, fire damper inspections, and IAQ solutions across Chichester, West Sussex, and the wider South of England. We're also one of the only suppliers of bipolar ionisation cleaning technology in the South of England — if you're interested in keeping your ventilation system cleaner for longer, contact us and let us know your requirements.