Your library lent you a lead test. Here is how to use it.

New Hampshire's Healthy Homes and Lead Poisoning Prevention Program put these kits in libraries across the state so anyone can check their own house without paying for it. Takes about a minute per spot. You do not need to know anything going in.

51.5%
of New Hampshire homes were built before lead paint was banned in 1978
22%
were built before 1950, when the paint was at its most leaded
129
of the state's 243 towns with housing are majority pre-1978

Look up your own town

Every town in New Hampshire, from the Census Bureau's American Community Survey. This is the housing stock where you live, not a guess. Older housing is the single best predictor of whether lead paint is in a building.

Source: U.S. Census Bureau, American Community Survey 5-year estimates 2024, tables B25034 and B01003. All 243 New Hampshire towns that have housing are here. 234 of them carry a combined need rank. The rest are small enough that the Census could not produce a reliable child-poverty estimate, so they show housing age only.

Using the kit

Three parts in the box: a spray bottle, a UV flashlight, and a reference card. Do it in a dim room. Bathrooms and closets work well because you can shut the door.

1
Pick a spot worth checking. Window sills, door frames, baseboards, stair rails, anywhere paint is chipping or two surfaces rub together. On dishes, aim at the painted decoration or the rim, not the plain white.
2
Mist it lightly, or tap one drop on. A drop is better than a spray when you are hunting for a faint result. Do not rub it in with a cotton ball, the swabbing motion can knock a weak positive loose before you see it.
3
Shine the UV light on it. Lead lights up bright green within a few seconds. Then wait for the drop to dry and look again. That second look is the one that counts.

A full bottle is good for roughly 3,600 tests, so you are not going to run it dry. Check everything you are curious about.

★ Read this part twice

The one thing to remember: lead persists, reflections do not.

This is where almost everybody gets confused, so it is worth reading twice.

A distinct bright green that appears after you spray and is still there once the drop has dried, locked to the exact spot, is lead. Brighter means more of it. If you see tiny specks drifting with the liquid, that is worse.
Anything that was already glowing before you sprayed is not lead. Lots of ordinary things fluoresce under UV on their own: certain glazes, plastics, laundry brighteners. Same for a faint blue-green that only shows while the surface is wet and vanishes as it dries. That is the alcohol catching light, not a reaction.

If a result has you unsure, photograph the dried spot under the UV light in the dark and email it to eric@fluorospect.com. A person reads it, not a bot.

It glowed. Now what.

First, do not panic, and do not start scraping anything. Lead paint sitting under later coats, intact and not chipping, is sealed. It is not doing anything to you. The danger is dust, and dust comes from friction and from demolition, not from paint that is just sitting there.

If it is paint in the house

Leave it alone and control the dust. Wet wipe window sills and floors weekly, because dry sweeping just throws it back into the air. Vacuum with a HEPA filter. Wash hands before meals, especially little kids' hands. If you are planning to sand, scrape, or knock down a wall, that is the moment to stop and get someone licensed involved, because that is what actually puts lead into the air.

If it is a dish or a mug

Keep food and drink off the decorated part. A positive piece is completely fine to own, display, or keep in a cabinet. It only matters when you eat off it or let food sit on it. Gold-decorated china is the worst category there is.

If you have young kids

Ask your pediatrician for a blood lead test. It is a routine draw and most kids get one at ages one and two anyway. It measures what actually got into your child instead of what might have, and knowing beats worrying. New Hampshire's program can walk you through what a number means.

What this kit is, and what it is not

It is a screening tool. It tells you fast and for free whether there is lead in front of you, so you know where to look and what to keep your kids away from. That is genuinely useful and it is what it is good at.

It is not a legal lead inspection or a risk assessment. Those have to be done by a licensed lead inspector or risk assessor, and this does not substitute for one or carry any weight in a real estate transaction, a rental dispute, or a code enforcement matter. It is also not a blood test, and it does not detect cadmium or arsenic.

It reads lead in paint and glaze. It cannot see the trace, parts-per-billion amounts you hear about in food and consumer products, which are thousands of times lower than what this chemistry responds to.

When you are done with it

Bring it back to the library so the next person can use it. If something broke, leaked, or the light will not turn on, tell me and I will replace it, no charge and nothing to send back.

New Hampshire's lead program

The Healthy Homes and Lead Poisoning Prevention Program at NH DHHS runs this loaner program and has people who help families with lead in their homes. Their program page is here, and their childhood lead data portal is on the state WISDOM portal.

Questions about a result

Email eric@fluorospect.com or call 631-461-1838. Send photos. I answer these myself.

Want one of your own?

The borrowed one goes back to the library. If you want to keep testing, or hand one to family, the same kit is on our site. One bottle covers thousands of tests, so it tends to last as long as you have questions.