Lead paint and renovation dust: a metal hazard we cannot see

Lead-based paint was sold for US residential use until 1978 (banned by the Consumer Product Safety Commission); Canada extended permitted use later but the typical cutoff is 1992. The older the house, the higher the probability of lead in interior trim, exterior siding, and high-friction surfaces (window jambs, door casings, stair treads). HUD estimates 87% of pre-1940 US homes contain some lead paint; the rate drops sharply after 1960.

Terrestream's PM10 channel sees particulate mass, not particulate composition. Lead-laden dust looks exactly like any other dust to a 660 nm laser scatter sensor; the readings during a renovation can be modest and the lead exposure can be substantial at the same time. A wipe sample analyzed by lab GFAAS or XRF will tell you whether the dust has lead in it; an air sensor will not. Children under 6, and pregnant women, are the highest-risk populations because the developing brain is uniquely vulnerable to lead.

If the home was built before 1978 and you are doing any renovation that disturbs more than 6 ft² of interior or 20 ft² of exterior painted surface, US federal law requires the contractor to be EPA RRP-certified. The contractor must use plastic containment, HEPA vacuums (not shop vacuums), wet methods (not dry sanding), and a final clearance test before the work area is reoccupied. Doing it yourself? You are still bound by the rule if anyone outside your family will live there or if children under six live there.

Children in older homes should be blood-lead tested per CDC guidance (most pediatricians screen at 12 and 24 months in Medicaid-covered or high-risk-zip-code populations). Adults working in renovation, demolition, or radiator repair should be tested under NIOSH occupational guidelines. None of this is something the dashboard can do for you; it is a different category of hazard.