Lewisham Diffusion Tubes
Cerys Williams
2026-07-28
knitr::opts_chunk$set(echo = FALSE, message = FALSE, warning = FALSE)Lewisham Air Quality Monitoring – Proposals for Change
Executive Summary
Lewisham’s air quality monitoring network currently consists of five continuous reference monitors and 162 diffusion tubes changed monthly by a contractor. While diffusion tubes provide broad spatial coverage, they are costly (£19,409 per year including contractor fees) and limited to monthly averages, restricting their ability to capture short‑term pollution episodes, diurnal patterns, or acute exposure risks. Sensors cannot be used to assess compliance with statutory limits but they play an increasingly important role in public information, engagement, and local exposure assessment.
Lewisham already operates 6 Praxis Cube multi‑pollutant sensors, and a further 11 MCERTS‑certified multi-pollutant sensors will be added in 2026 through existing funding. These additions significantly enhance the borough’s real‑time monitoring capability and provide a strong foundation for expanding non‑statutory monitoring to support public health messaging and community engagement.
The recent Coroner’s concerns emphasise the need for more granular, real‑time public information to help residents reduce exposure during high‑pollution periods. Diffusion tubes alone cannot meet this expectation. Modern sensor technologies—MCERTS‑certified particulate monitors, low‑cost outdoor sensors (AirGradient), indoor monitors (AirGradient Indoor, Airthings View Plus), and mobile personal exposure devices (Atmotube PRO)—offer flexible, scalable options that complement statutory monitoring and strengthen public access to timely information.
Reducing diffusion tube numbers by 50–75% would release £9,704–£14,556 annually, enabling substantial reinvestment in real‑time sensors without increasing overall budget. This creates a strong financial case for rebalancing the network while retaining statutory compliance through reference monitors.
A mixed monitoring strategy offers the best balance of accuracy, cost efficiency, and public value. A small number of MCERTS sensors should be deployed at strategic locations to anchor the network and validate low‑cost devices. Borough‑wide coverage could be expanded using AirGradient outdoor sensors, which provide high‑resolution real‑time data at very low cost. Indoor sensors could be deployed selectively in schools and vulnerable settings, while Atmotube mobile sensors or similar can support engagement, personal exposure studies, and hotspot investigation.
This approach directly addresses the Coroner’s concerns by improving public access to timely, detailed air quality information, enabling residents to make informed decisions during pollution episodes. It also reduces recurring costs, increases flexibility, and strengthens Lewisham’s ability to target interventions, support schools, and engage communities.
Recommendation:
Lewisham should adopt a phased transition toward a sensor‑led monitoring
network, reducing diffusion tube numbers and reinvesting savings into a
mixed portfolio of MCERTS, low‑cost outdoor, indoor, and mobile sensors.
This strategy enhances public information, supports community
engagement, complements statutory monitoring, and provides the most
cost‑effective and future‑proof approach for the borough.
Introduction
The purpose of this document is to review Lewisham’s current air quality monitoring arrangements and consider whether they remain fit for purpose. In doing so, it asks three core questions:
1. What do we want to learn from the data?
Is the primary aim to track compliance with statutory objectives, to
understand local exposure hotspots, or to evaluate the impact of
specific interventions? Each purpose requires a different level of
spatial and temporal resolution, and not all monitoring technologies are
equally suited to every question.
2. Do we need new equipment to answer these
questions?
In many cases, existing reference‑grade monitors—supported by modelled
background maps, diffusion tube networks, or targeted short‑term
studies—may already provide sufficient evidence. Before expanding the
network, it is important to establish whether the desired insight
genuinely requires additional instrumentation or whether improvements in
analysis, validation, or integration would achieve the same outcome.
3. What are the available options?
Low‑cost sensors can increase spatial coverage and support community
engagement, but they introduce greater uncertainty and require careful
calibration and interpretation. Reference‑grade monitors and a diffusion
tube network remain essential for statutory compliance and long‑term
trend analysis. Diffusion tubes offer excellent spatial coverage at low
cost, but they are limited to monthly averages and cannot capture
short‑term peaks, diurnal patterns, or episodic events that may
significantly influence annual mean exposure. In some cases, mobile
monitoring, short‑term deployments, or enhanced modelling may provide
more actionable insight than permanent installations.
Ultimately, changes to the monitoring network should be driven by clear evidence of gaps in spatial coverage, suspected localised sources contributing disproportionately to exposure, or a need for more granular temporal information. In many situations, strengthening data quality, validation processes, and integration with public health evidence may deliver greater value than simply adding more monitors.
A potential future direction is the development of a citizen‑science programme. Such initiatives can broaden monitoring coverage, reveal hidden vulnerabilities, and give communities a stronger voice in shaping fairer policies. However, challenges remain around data quality, integration with formal reporting frameworks, and ensuring inclusive participation without inadvertently excluding or stigmatizing vulnerable groups.
Current Situation
Five continuous monitoring stations were operational within the London Borough of Lewisham (LBL) during 2025. The former LW1 Catford site—now designated LW6—was relocated in November 2021 to Laurence House, 1 Catford Road, where it continues to measure nitrogen dioxide (NO₂). The Deptford site (LW5), also measuring NO₂, was decommissioned in April 2025. A Defra funded project enabled the instillation of six Praxis Cubes during 2025 and during 2026 a further 11 sensors will be installed, likely to be Airlys. The Council also undertake non-automatic (diffusion tube) monitoring of NO2 at 148 locations.
The following charts illustrate current monitoring coverage in Lewisham and also the concentrations of Nitrogen dioxide that they measure. This information can be used too determine the usefulness of the data that is being collected and where are the gaps.
Core Data
- Diffusion tubes (2019–2025) +
- LAEI 2022 traffic data major roads
- AQMA boundaries
| year | 20–25 µg/m³ | 25–30 µg/m³ | >30 µg/m³ | NA | 15–20 µg/m³ | <15 µg/m³ |
|---|---|---|---|---|---|---|
| 2019 | 12 | 18 | 20 | 98 | 0 | 0 |
| 2020 | 40 | 22 | 5 | 49 | 32 | 0 |
| 2021 | 38 | 17 | 6 | 47 | 39 | 1 |
| 2022 | 41 | 20 | 7 | 8 | 68 | 4 |
| 2023 | 38 | 12 | 6 | 4 | 74 | 14 |
| 2024 | 28 | 13 | 3 | 2 | 68 | 34 |
| 2025 | 34 | 12 | 2 | 0 | 76 | 24 |
Diffusion tube locations and concentrations (1999 - 2025), with major roads and AQMA boundaries.
Locations with concentrations above 25µg/m3 within 5km of a road.
Locations with concentrations below 15µg/m3 within 5km of a road.
What next?
Coroner’s Concerns
In the Prevention of Future Deaths (‘PFD’) report for the inquest of Ella Adoo Kissi-Debrah, the Coroner identified several issues that pose a continuing risk unless further action is taken. One of the key concerns relevant to Lewisham’s monitoring strategy was the low level of public awareness about air pollution information sources, such as the UK‑Air website and local pollution alerts. The Coroner noted that improving public access to timely, detailed air quality information could help individuals reduce their personal exposure, particularly during high‑pollution episodes.
The Coroner also highlighted that providing sufficiently granular and locally relevant information is likely to require expanded monitoring capacity, including an increased number of air quality sensors. This expectation applies to both national and local government.
This creates a clear strategic question for Lewisham: how can the borough strengthen public access to reliable, real‑time air quality information while maintaining a monitoring network that is proportionate, cost‑effective, and aligned with statutory requirements?
Proposals for Change
Proposal 1 — Maintain the current monitoring approach, but expand the sensor network using external funding
This option preserves the existing balance of reference monitors, sensors and diffusion tubes while adding an additional modest number of low‑cost or MCERTS‑indicative certified sensors. It is operationally simple and low‑risk. However, diffusion tubes remain the dominant source of spatial data, meaning monthly averages continue to limit temporal insight. Public access to real‑time information improves, but only incrementally.
Proposal 2 — Gradually shift towards a sensor‑led network, reducing reliance on diffusion tubes
This option shifts Lewisham toward a more modern, sensor‑led monitoring network. Reducing diffusion tube numbers frees up recurring budget that can be reinvested in low‑cost sensors, MCERTS‑certified particulate monitors, or personal/indoor monitoring devices. This approach directly addresses the Coroner’s concerns by increasing the availability of detailed, real‑time information and enabling more targeted public health messaging.
It does, however, require careful planning around calibration, QA/QC, and integration with existing reporting frameworks.
| Tube Reduction | Annual Saving |
|---|---|
| 25% (40 tubes) | £1,836 |
| 50% (80 tubes) | £3,672 |
| 75% (120 tubes) | £5,508 |
A key consideration under this proposal is what types of sensors to purchase and how they will be deployed. Options include:
- Ambient outdoor sensors (multi‑pollutant, low‑cost)
to increase spatial coverage
- Personal exposure sensors to support targeted
studies or community engagement
- Indoor air quality sensors for schools, workplaces,
or vulnerable households
This approach aligns with the Coroner’s concerns by improving public access to detailed, timely information, but it requires careful planning around data quality, calibration, and integration with existing reporting frameworks.
Decision‑Making Matrix: Options for Evolving Lewisham’s Air Quality Monitoring Network This matrix compares the two proposals currently under consideration, incorporating known costs, operational implications, and alignment with the Coroner’s concerns regarding public access to detailed, real‑time air quality information.
Costed Scenario Analysis: Expansion of Lewisham’s Sensor Network
This analysis models the financial implications of expanding
Lewisham’s air quality sensor network under three deployment scenarios:
10 sensors, 20 sensors, and 50
sensors.
Costs are based on currently available pricing for Breathe
London (Airly) MCERTS‑certified sensors, with optional
comparison to AirGradient Open Air (non‑MCERTS,
low‑cost, used by Reading and other Local Authorities for
engagement).
Diffusion tube costs are included to show potential savings if Lewisham reduces tube numbers under Proposal 2.
1. Baseline Costs
Diffusion Tubes (Current)
- 160 tubes
- £3.75 per tube per month
- 12 months
- Annual cost: £7,344
- Tubes: £7,200
- Carriage: £144
- Tubes: £7,200
If Lewisham reduces tube numbers, savings scale linearly:
| Tube Reduction | Annual Saving |
|---|---|
| 25% (40 tubes) | £1,836 |
| 50% (80 tubes) | £3,672 |
| 75% (120 tubes) | £5,508 |
These savings can be reinvested into sensors under Proposal 2.
2. Sensor Cost Assumptions
Breathe London / Airly (MCERTS PM)
- 3‑year contract (non‑solar): £4,085 per sensor
- 5‑year contract (non‑solar): £6,075 per sensor
- Annual MCERTS removal/reinstallation: £350 per sensor
AirGradient Open Air
- Assembled: USD225 (~£175)
- Kit: USD125 (~£95)
- No MCERTS
- Suitable for engagement, schools, citizen science
3. Scenario Costs (MCERTS Sensors)
Scenario A — 10 Sensors
3‑Year Contract - Sensor cost: 10 × £4,085 = £40,850 - Calibration every 2 years 10 × £350 = £3,500 - Total 3‑year cost: £44,350
5‑Year Contract - Sensor cost: 10 × £6,075 = £60,750 - Calibration every 2 years: 10 × £350 × 2 = £7,000 - Total 5‑year cost: £67,750
Scenario B — 20 Sensors
3‑Year Contract - Sensor cost: 20 × £4,085 = £81,700 - Calibration every 2 years: 20 × £350 = £7,000 - Total 3‑year cost: £88,700
5‑Year Contract - Sensor cost: 20 × £6,075 = £121,500 - Calibration every 2 years: 20 × £350 × 2 = £14,000 - Total 5‑year cost: £135,500
Scenario C — 50 Sensors
3‑Year Contract - Sensor cost: 50 × £4,085 = £204,250 - Calibration every 2 years: 50 × £350 = £17,500 - Total 3‑year cost: £221,750
5‑Year Contract - Sensor cost: 50 × £6,075 = £303,750 - Calibration every 2 years: 50 × £350 × 2 = £35,500 - Total 5‑year cost: £339,250
4. AirGradient Scenario Costs (Non‑MCERTS)
These are dramatically cheaper and suitable for:
- schools
- indoor monitoring
- citizen science
- engagement
- hotspot investigation
10 Sensors
- 10 × £175 = £1,750
20 Sensors
- 20 × £175 = £3,500
50 Sensors
- 50 × £175 = £8,750
These basic sensors do not require data management like the Praxis Cube or Airly. However it would be prudent for a member of staff to sense check the data on a regular basis and collocating the sensor with a reference monitor for 2 weeks once a year would only enhance the data collected.
5. Combined Strategy Options
Option A — MCERTS + AirGradient Mix
For example:
- 10 MCERTS sensors (compliance + public alerts)
- 20 AirGradient sensors (schools + engagement)
Cost (3‑year): - MCERTS: £44,350
- AirGradient: £3,500
- Total: £47,850
Option B — Reduce Diffusion Tubes by 50%
Savings: £3,672 per year
This could fund: - 21 AirGradient sensors per year,
or
- 1 MCERTS sensor every 1.1 years
6. Management Interpretation
10 Sensors
- Modest expansion
- Good for hotspot validation and public alerts
- Low operational burden
20 Sensors
- Borough‑wide coverage
- Supports school engagement, public dashboards, and targeted
interventions
- Strong alignment with Coroner’s concerns
50 Sensors
- High‑resolution network
- Enables street‑level mapping and real‑time public exposure
reduction
- Significant cost; requires robust QA/QC and data management
Total Cost Comparison Chart (10, 20, 50 sensors)
Annualised Cost Comparison Chart
Cost per Sensor Type (Unit Cost Chart)
## *Air Quality Monitoring – Risk Register**
This risk register compares the two strategic proposals:
- Proposal 1: Maintain current monitoring network +
expand sensors using MAQF funding
- Proposal 2: Expand sensors + reduce diffusion tubes + reinvest savings
It also includes risks associated with specific technologies (MCERTS, AirGradient, Airthings, Atmotube).
1. Strategic Risks
| Risk | Description | Likelihood | Impact | Mitigation |
|---|---|---|---|---|
| Misalignment with Coroner’s concerns | If monitoring remains heavily reliant on diffusion tubes, Lewisham may not meet expectations for more granular, real‑time public information. | Medium | High | Expand sensor network; improve public dashboards; reduce tube reliance over time. |
| Insufficient spatial coverage | Maintaining current network may fail to identify localised hotspots or exposure risks. | Medium | Medium | Deploy low‑cost sensors in schools, residential areas, and suspected hotspots. |
| Over‑expansion without QA/QC | Rapid sensor deployment without calibration or validation could reduce data reliability. | Medium | High | Develop QA/QC protocol; pair low‑cost sensors with MCERTS reference points. |
| Technology obsolescence | Sensors may become outdated or unsupported within 3–5 years. | Medium | Medium | Choose open‑source or widely adopted platforms; plan for replacement cycles. |
2. Financial Risks
| Risk | Description | Likelihood | Impact | Mitigation |
|---|---|---|---|---|
| High recurring cost of diffusion tubes | Current annual cost (£19,409 including contractor) limits ability to invest in sensors. | High | High | Reduce tube numbers; reinvest savings into sensors. |
| High capital cost of MCERTS sensors | MCERTS sensors cost £4,085–£6,075 each + £350 annual maintenance. | High | High | Deploy only at strategic locations; supplement with low‑cost sensors. |
| Underestimating installation/maintenance costs | MCERTS sensors require annual removal/reinstallation (~£350). | Medium | Medium | Include full lifecycle costs in budgeting. |
| Exchange rate volatility (USD → GBP) | AirGradient indoor/outdoor pricing may fluctuate. | Medium | Low | Use conservative conversion rates; include contingency. |
3. Operational Risks
| Risk | Description | Likelihood | Impact | Mitigation |
|---|---|---|---|---|
| Data integration challenges | Multiple sensor types may produce inconsistent formats or require new workflows. | Medium | Medium | Standardise data ingestion; use platforms compatible with multiple devices. |
| Maintenance burden | Large sensor networks require regular checks, calibration, and replacement. | Medium | Medium | Assign dedicated resource; automate alerts; use robust hardware. |
| Indoor sensor deployment complexity | Schools and public buildings may require permissions, IT support, or safeguarding considerations. | Medium | Medium | Work with schools early; provide clear installation guidance. |
| Mobile sensor misuse or loss | Atmotube devices may be misplaced or used inconsistently. | Medium | Low | Provide training; assign devices to specific staff or schools. |
4. Data Quality Risks
| Risk | Description | Likelihood | Impact | Mitigation |
|---|---|---|---|---|
| Low‑cost sensor drift | AirGradient and Atmotube sensors may drift without calibration. | Medium | Medium | Pair with MCERTS sensors; periodic co‑location checks. |
| Indoor/outdoor data confusion | Indoor sensors may be misinterpreted as ambient air quality. | Medium | Medium | Clear labelling; separate dashboards for indoor vs outdoor. |
| Public misinterpretation of real‑time data | Real‑time data may cause concern without context. | Medium | Medium | Provide guidance notes; include health messaging; use thresholds. |
5. Reputational Risks
| Risk | Description | Likelihood | Impact | Mitigation |
|---|---|---|---|---|
| Perception of inaction | If Lewisham does not expand monitoring, public may feel concerns are not addressed. | Medium | High | Communicate improvements; publish dashboards; engage communities. |
| Over‑reliance on low‑cost sensors | Public may question accuracy if low‑cost sensors dominate. | Medium | Medium | Maintain MCERTS reference points; publish QA/QC approach. |
| Citizen science backlash | Poor data quality or unclear messaging could undermine trust. | Low | Medium | Provide training; use validated sensors; ensure transparency. |
6. Legal / Compliance Risks
| Risk | Description | Likelihood | Impact | Mitigation |
|---|---|---|---|---|
| Data privacy concerns (indoor/mobile sensors) | Personal exposure monitoring may raise GDPR issues. | Low | Medium | Avoid personal identifiers; use aggregated data; follow GDPR guidance. |
7. Technology‑Specific Risk Summary
MCERTS Sensors (Airly / Breathe London) -
Strength: High accuracy, compliance‑grade
- Risk: High cost, annual maintenance, installation
burden
AirGradient Outdoor - Strength:
Very low cost, flexible, open‑source
- Risk: Not MCERTS; requires QA/QC
AirGradient Indoor - Strength:
Affordable indoor monitoring
- Risk: Indoor readings may confuse public
messaging
Airthings View Plus - Strength:
Reliable indoor sensor with strong brand
- Risk: Higher cost; subscription features
Atmotube Mobile - Strength:
Excellent for engagement and personal exposure studies
- Risk: Easy to lose; inconsistent use patterns
Cost–Benefit Summary: Lewisham Air Quality Monitoring Options
This summary compares the costs and benefits of expanding Lewisham’s air quality monitoring network using a mix of MCERTS sensors, low‑cost sensors, indoor monitors, mobile devices, and potential reductions in diffusion tube use. It incorporates all updated costs, including the contractor fee for changing diffusion tubes (£1,005.42/month).
1. Financial Summary
Current Annual Cost of Diffusion Tubes
- Tubes + analysis: £7,344
- Contractor (changing 162 tubes): £12,065
- Total annual cost: £19,409
This is the baseline cost that could be partially or fully reallocated under Proposal 2.
Sensor Costs (Unit Prices)
| Sensor Type | Unit Cost | Notes |
|---|---|---|
| MCERTS Outdoor (Airly) | £4,085 (3‑yr) / £6,075 (5‑yr) | +£350 annual maintenance |
| AirGradient Outdoor | £175 | Non‑MCERTS |
| AirGradient Indoor | £179 | Non‑MCERTS |
| Airthings View Plus (Indoor) | £260 | Indoor IAQ |
| Atmotube PRO (Mobile) | £180 | Personal exposure |
Annual Savings from Tube Reduction
| Tube Reduction | Annual Saving |
|---|---|
| 25% | £4,852 |
| 50% | £9,704 |
| 75% | £14,556 |
| 100% | £19,409 |
These savings can be reinvested directly into sensors.
2. Benefits Summary
MCERTS Outdoor Sensors (Airly / Breathe London)
Benefits - Compliance‑grade particulate
monitoring
- High accuracy and reliability
- Strong alignment with Coroner’s concerns
- Suitable for public dashboards and alerts
Costs / Limitations - Very high capital cost
- Annual maintenance burden
- Installation/removal cost (~£350/year per unit)
- Best used sparingly at strategic locations
AirGradient Outdoor Sensors
Benefits - Extremely low cost
- Easy to deploy
- Open‑source and flexible
- Ideal for expanding spatial coverage
- Suitable for schools, community engagement, and hotspot mapping
Costs / Limitations - Not MCERTS
- Requires QA/QC and periodic co‑location
- Not suitable as standalone compliance evidence
Indoor Sensors (AirGradient Indoor / Airthings View Plus)
Benefits - Supports public health messaging
- Useful for schools, workplaces, vulnerable households
- Helps identify indoor pollution sources (cooking, heating,
ventilation)
- Complements outdoor network
Costs / Limitations - Indoor readings must be
clearly separated from ambient AQ data
- Higher unit cost (Airthings)
- Requires permissions and installation planning
Atmotube PRO Mobile Sensors
Benefits - Excellent for personal exposure
studies
- Highly flexible and portable
- Ideal for citizen science, school projects, hotspot
investigation
- Very low cost
Costs / Limitations - Not fixed-location
monitoring
- Data consistency depends on user behaviour
- Devices can be lost or misused
3. Strategic Benefits by Proposal
Proposal 1 — Maintain tubes + add sensors (MAQF funding)
Benefits - Low operational disruption
- Retains statutory tube network
- Adds real‑time capability
- Incremental improvement
Limitations - Diffusion tubes remain dominant
- Limited alignment with Coroner’s concerns
- High recurring tube + contractor cost remains
- Less flexibility for future expansion
Proposal 2 — Reduce tubes + expand sensors + reinvest savings
Benefits - Strong alignment with Coroner’s
concerns
- Major recurring savings (£4,852–£19,409/year)
- Enables rapid expansion of sensor network
- Supports public dashboards, school engagement, citizen science
- More granular temporal data (peaks, diurnal patterns, episodes)
- Flexible mix of MCERTS + low‑cost sensors
Limitations - Requires QA/QC strategy
- Requires careful planning for sensor deployment
- Indoor/mobile data must be clearly communicated
4. Cost–Benefit Conclusions
High‑Value Investments
- AirGradient Outdoor: best cost–coverage ratio;
ideal for borough‑wide expansion
- Atmotube PRO: best for engagement and personal
exposure studies
- AirGradient Indoor: low‑cost indoor monitoring for schools and vulnerable groups
Strategic Investments
- MCERTS sensors: essential for compliance and high‑confidence public alerts; should be deployed sparingly at key locations
Low‑Value Investments
- Maintaining full diffusion tube network: high recurring cost (£19,409/year) with limited temporal resolution
Best Overall Approach
A mixed network combining:
- a small number of MCERTS sensors
- a large number of AirGradient outdoor sensors
- targeted indoor sensors
- mobile Atmotube devices for engagement
- reduced diffusion tube network
This approach: - maximises spatial coverage
- improves real‑time public information
- reduces recurring costs
- aligns with Coroner’s concerns
- supports schools and communities
- maintains statutory compliance
Here’s a clear, concise, management‑ready recommendation section that follows naturally from your cost–benefit summary and prioritisation matrix. It is written in a professional, strategic tone suitable for an internal decision‑making document.
Suggestion
Based on the cost analysis, risk register, prioritisation matrix, and the Coroner’s concerns regarding the need for more granular, real‑time public information, the following suggestions are proposed for Lewisham’s air quality monitoring strategy.
1. Transition toward a sensor‑led monitoring network
Lewisham should begin a phased shift away from reliance on diffusion tubes and toward a mixed sensor network that provides higher temporal resolution, improved public accessibility, and greater flexibility. Diffusion tubes remain useful for long‑term trend analysis, but their limited temporal resolution and high recurring cost (£19,409/year including contractor fees) make them less suitable as the backbone of a modern monitoring system.
A reduction of 50–75% in tube numbers would release £9,704–£14,556 per year, enabling significant reinvestment in real‑time sensors.
2. Deploy a small number of MCERTS‑certified sensors at strategic locations
MCERTS sensors (Airly/Breathe London) provide MCERTS‑grade particulate data and should be used sparingly at key sites where:
- high‑confidence public alerts are required
- data will be used for statutory reporting
- validation of low‑cost sensors is needed
A recommended deployment is 5–10 MCERTS sensors, balancing accuracy with cost.
3. Expand borough‑wide coverage using low‑cost outdoor sensors
AirGradient outdoor sensors offer the best cost‑coverage ratio and are easy to deploy across schools, residential areas, and suspected hotspots. They strongly support the Coroner’s concerns by enabling:
- real‑time public dashboards
- hyperlocal exposure information
- identification of short‑term pollution episodes
- community engagement
Savings from diffusion tube reduction could fund 50–100 AirGradient sensors, creating a borough‑wide network at minimal cost.
4. Introduce indoor monitoring in targeted settings
Indoor air quality is increasingly recognised as a public health priority. A small number of indoor monitors (AirGradient Indoor or Airthings View Plus) should be deployed in:
- schools
- council buildings
- settings with vulnerable populations
This supports public health messaging and complements outdoor monitoring.
Recommended deployment: 10–20 indoor monitors.
5. Use mobile sensors (Atmotube PRO) for engagement and targeted studies
Mobile sensors provide valuable insight into personal exposure and are ideal for:
- school projects
- citizen science
- hotspot investigations
- short‑term studies
They are low‑cost and highly flexible. A recommended deployment is 20–50 Atmotube devices for community and educational use.
6. Develop a QA/QC and data integration framework
A mixed network requires a clear approach to:
- calibration
- co‑location checks
- data validation
- integration into dashboards
- communication of indoor vs outdoor readings
This ensures public confidence and prevents misinterpretation.
7. Strengthen public communication and real‑time information access
To address the Coroner’s concerns, Lewisham should:
- publish real‑time air quality dashboards
- provide guidance on exposure reduction
- promote awareness of UK‑Air and local monitoring tools
- integrate sensor data into public‑facing platforms
Input from public health teams and data scientists will enable Lewisham make the best use of the data collcted. This will help residents make informed decisions during pollution episodes.
Overall Recommendation
Lewisham should adopt Proposal 2:
Reduce diffusion tube numbers and reinvest savings into a mixed
sensor network, combining:
- a small number of MCERTS sensors
- a large number of low‑cost outdoor sensors
- targeted indoor monitors
- mobile sensors for engagement
This approach:
- aligns strongly with the Coroner’s concerns
- improves real‑time public information
- expands spatial coverage
- reduces recurring costs
- supports schools and communities
- maintains statutory compliance
- provides flexibility for future growth
It represents the most cost‑effective, future‑proof, and strategically aligned option for Lewisham’s air quality monitoring network.