How It Works

From existing lamppost
to active air cleaner.

Four stages. One column. No excavation. The full technical story of how we transform Britain's existing street infrastructure into a distributed clean air network.

Everything in one column.

The Clean Air Initiative column integrates air filtration, low-power cellular connectivity, and environmental sensing into a complete replacement lighting column — factory-fitted, connecting to the stub of the existing post.

01
The Column

A complete replacement column, factory-fitted with the full filtration stack and sensing system, connecting to the stub of the existing post — reusing the foundation and power supply already in the ground, with a connection section that adapts to site condition. Available in standard RAL colours to match local street furniture specifications.

Installation by existing lamppost maintenance contractors — the same teams that change bulbs and service street lighting. No specialist skills. No heavy plant. No road closures.

Diameter
300–400mm outer · fits all standard UK lamppost stubs
Height
1,200mm — occupies the stub section below the main column
Material
Marine-grade aluminium (6061-T6) or GRP composite
Finish
Polyester powder coat · standard RAL colours
Weight
Under 35kg complete assembly
Installation
One MEWP, two operatives — an estimated 2–3 hours per post, several posts per crew per day
existing lantern — remounted Sensors & comms Section 3 — riser Outlet clean air out · sensor Fan Filtration stack ×4 Section 2 Intake dirty air in · sensor Connection Section 1 existing stub — reused three sections · one diameter
02
Four-Stage Filtration

Air is drawn in through the ground-level intake grille at 100–200mm above pavement — the height where pollution is most concentrated. It passes through four filtration stages before being exhausted as clean air above head height.

The filtration cartridge is a single modular unit, secured behind a tool-access maintenance panel so it stays tamper-resistant on a public street while remaining quick for an authorised technician to swap during routine visits. Target replacement interval: 6–12 months.

Polluted air in Stage 1 · Electrostatic Pre-filter Removes large particles (PM10+) Stage 2 · HEPA H14 99.995% of fine particles (PM2.5) Stage 3 · Activated Carbon Adsorbs NO₂ and VOCs (40–70%) Stage 4 · TiO₂ Photocatalytic UV-A activated · breaks down residual NO₂ Clean air out Fan 300–500 m³/h

Four stages. Maximum removal.

Dirty air in at exhaust-pipe height. Clean air out at breathing height.
The intake sits low on the column, where kerbside pollution is thickest. Cleaned air returns just above head height — delivering the benefit into the air people actually breathe, with intake and outlet kept well apart so the unit never recirculates its own output.
Serviced in minutes. Refurbished, not landfilled.
Each filtration stage is a sealed, swappable cartridge, changed at street level in minutes by one person with one van — no road closures, no access platforms. Spent cartridges return to a depot for refurbishment and reuse.

Each stage targets a different class of pollutant. Together they achieve near-total removal of the most harmful particles and gases from processed air.

1
Electrostatic Pre-filter
Charges incoming particles electrostatically, causing them to adhere to the filter media. Removes large particles (PM10 and above) and reduces loading on downstream filters. Self-cleaning mesh. Replaced as part of cartridge service.
>90%
removal of particles >1 micron
2
HEPA H14 Filter
High-Efficiency Particulate Air filter to EN 1822 H14 standard. Primary PM2.5 removal stage. Differential pressure sensor monitors filter loading and triggers replacement alerts when saturation threshold is reached.
99.995%
removal of particles ≥0.3 microns
3
Activated Carbon Filter
Granular activated carbon (GAC) bed. Removes NO₂, VOCs, and odorous compounds by adsorption. Replacement interval 6–12 months depending on local NO₂ concentration. 2–4kg of GAC per unit.
40–70%
NO₂ removal from processed air
4
TiO₂ Photocatalytic Layer
Titanium dioxide photocatalytic coating activated by integrated UV-A LED array (365nm). Breaks down residual NO₂, VOCs, and biological contaminants through photocatalytic oxidation. Produces no ozone at UV-A wavelengths. TiO₂ coating permanent — UV LED replaced on service schedule.
50–75%
combined NO₂ removal (stages 3+4)

Every unit connected.
No cables, no single point of failure.

Each unit carries its own low-power cellular IoT module (NB-IoT / LTE-M) — the same class of connectivity used by councils’ existing smart streetlight systems. No fibre, no pavement works, no shared hub: every post reports independently, so a damaged unit takes out one data point, not a street. A unit that goes silent is itself an alert. For off-grid sites — rural roads, motorways, export markets — a satellite-connected variant is available.

📶 Mobile network NB-IoT / LTE-M 💡 💡 💡 💡 💡 💡 💡 💡 💡 💡 Every post independently connected — one damaged unit never takes the street’s data down A unit that stops reporting raises its own fault alert Pounds, not tens of pounds, per post per month
1 per post
Every unit carries its own cellular module — no shared hub, no single point of failure
<2W
Connectivity power draw — a fraction of a satellite terminal, handing watts back to the fan
Off-grid ready
Connectivity-agnostic design — satellite variant for rural roads and export markets without cellular coverage

Within existing circuit capacity.

The unit runs from the existing street lighting circuit. The exact power budget — how much air the fan can move within a column's supply — is precisely what our current CFD engineering study is quantifying: we publish measured figures, not guesses. Connectivity and sensing draw single-digit watts; the fan is the main load.

Component power draw — indicative pre-study estimates; our CFD study is quantifying the real figures
Fan (full speed)
60–80W
Filtration electronics
20–30W
Sensors & controller
5–10W
Cellular IoT module
<2W
LED light head
30–50W
Sensing & connectivity
Under 10W
Net grid draw
Set by CFD study
Whether the full fan duty fits within a given column's circuit is exactly what our CFD study and site surveys will confirm — measured, not assumed.