Air quality is the least visible risk on most sites — you can see an unguarded machine, but you cannot see respirable dust. This guide covers the parameters we measure most often and what each one tells you.

The parameters that matter

  • PM2.5 and PM10 — particulate matter small enough to reach deep into the lungs. The workhorse indicators for construction dust, quarrying, cement, and traffic corridors.
  • SO₂ and NOx — combustion gases from boilers, kilns, generators, and heavy vehicles. Key for any site burning fuel at scale.
  • VOCs — volatile organic compounds from solvents, paints, and fuel handling. Often the dominant indoor exposure in workshops.
  • CO and CO₂ — the first tells you about incomplete combustion and acute risk; the second is a fast proxy for poor ventilation indoors.
  • Noise — not strictly air quality, but usually monitored on the same programme because the receptors and reporting cycles overlap.

Baseline first, always

If a project is new, measure before it starts. A baseline study is the only defensible way to separate your impact from what was already in the air — and the one thing you cannot reconstruct later. Twelve months of seasonal coverage is the gold standard; a shorter campaign can work if it captures both wet and dry seasons.

What makes data defensible

  1. Calibrated instruments with traceable certificates.
  2. Receptor locations chosen for exposure, not convenience — the school downwind matters more than the fence line upwind.
  3. Sampling durations matched to the standard you're comparing against (24-hour averages compared to 24-hour limits, not spot readings).
  4. A chain of custody from field sheet to final report.

Cutting any of these corners produces numbers, not evidence. When a regulator or an international auditor questions the data, only evidence survives.

Reading the results

Comparing results against Uganda's national standards and WHO guideline values side by side is good practice: the national standard tells you about compliance, the WHO value tells you about health. When the two disagree, the gap is your improvement roadmap.

Planning a monitoring programme? Get in touch and we'll help you scope receptors, parameters, and frequency before you commit to a budget.