Asbestos testing: accredited labs, what they do with your sample, and who may take it
213 lab sites accredited for asbestos fiber analysis by NIST NVLAP, by state. As listed on November 7, 2026.
What the list is
NIST runs the National Voluntary Laboratory Accreditation Program (NVLAP). Its program page says the Asbestos Fiber Analysis program “provides assurance that laboratories are competent to analyze asbestos samples using polarized light microscopy (PLM) and/or transmission electron microscopy (TEM)”[1]. It lists two parts: bulk samples by PLM and airborne samples by TEM[1].
On November 7, 2026 the NVLAP directory listed 213 U.S. lab sites of 170 firms in 39 states and territories[2]. Their scope documents show 212 sites accredited for bulk analysis (PLM) and 67 sites for airborne analysis (TEM).
Each lab page below shows the lab code, the accreditation expiry date and the test methods as printed on the lab’s NVLAP scope document. A listing is not an endorsement, and the directory does not say whether a lab accepts samples from homeowners. Confirm the test you need with the lab before you send samples.
As listed by NIST NVLAPNovember 7, 2026
213 lab sites · 170 firms. Business details only; we do not publish contact persons.
17 listed labs print a homeowner price on their own websites. Printed lab fees for one standard bulk sample run from $20.00 to $95.00. See the price comparison (read November 13, 2026).
Asbestos test kit vs lab: what a home kit really is and when to use an accredited lab The asbestos test kits we read are a bag, gloves and a mailer; the test happens in a lab. Here is what kit sellers publish about lab fees and labs, how to check a kit's lab in the NIST directory, what one sample can and cannot show, and when a state or OSHA rule makes a kit result not enough.
How to test a popcorn ceiling for asbestos: what the ban dates mean, how many samples, and what to do with the result Only a lab can tell you whether a popcorn ceiling contains asbestos. Here is what the federal bans actually covered and when, how many samples a ceiling needs under the federal sampling standard, why paint and drywall layers are reported separately, what several states say about who may sample, one lab's published prices, and what the agencies say to do with each result.
The short answer: an asbestos test is a lab looking at a small piece of building material under a polarized light microscope and estimating how much of it is asbestos. The number that matters is 1 percent. Federal rules call a material asbestos-containing when it has "more than 1 percent asbestos," measured by a set method. Who is allowed to cut the sample out of your wall depends on your state.
First, the U.S. Environmental Protection Agency (EPA) on whether to test at all: "If building materials in your home aren't damaged and won't be disturbed, you do not need to have your home tested for asbestos."
Two kinds of asbestos test: material and air
Most homeowner questions are answered by a bulk test: a piece of material (ceiling texture, floor tile, pipe wrap, joint compound) goes to the lab, which reports whether asbestos is present, which type, and roughly how much. NIST's NVLAP program lists two parts for asbestos labs: bulk samples analyzed by polarized light microscopy (PLM), and airborne samples analyzed by transmission electron microscopy (TEM).
An air test is a different job. A pump pulls a measured volume of air through a filter, and the lab counts the fibers or structures on that filter. In the federal clearance rules and in EPA's homeowner advice, air testing comes after asbestos work, to check that the space is clean. It cannot tell you whether the ceiling above you contains asbestos.
Looking will not tell you either. EPA: "Generally, you can't tell whether a material contains asbestos simply by looking at it, unless it is labeled. If in doubt, treat the material as if it contains asbestos and leave it alone." EPA's list of places it may be found in homes includes vermiculite attic insulation, vinyl floor tiles and sheet-flooring backing, roofing and siding shingles, and "textured paint and patching compounds used on walls and ceilings."
What the lab does with a bulk sample
Nearly every accredited lab on the NVLAP list (209 of 213 U.S. sites) has EPA's Method for the Determination of Asbestos in Bulk Building Materials, EPA/600/R-93/116, dated July 1993, on its scope. Its introduction states the order of work: "An analysis with a simple stereomicroscope is always followed by a polarized light microscopic (PLM) analysis."
Stereomicroscope first. A low-magnification look at layers, texture and color, which the method calls "mandatory for all samples."
PLM identification. Fibers are mounted in liquids of known refractive index; optical properties such as refractive index, birefringence and extinction tell an asbestos mineral from cellulose, fiberglass and other fibers.
Quantitation. A calibrated visual estimate or a point count of how much is asbestos.
The older federal method is still the one the rules name. Appendix E to 40 CFR 763 Subpart E (the "Interim Method of the Determination of Asbestos in Bulk Insulation Samples") is the method the federal air rule for asbestos, the asbestos NESHAP, cites in its definitions of asbestos-containing material. NIST's handbook for bulk labs says NVLAP labs using the 1993 method "must be accredited for use of the method and indicate it on their test reports," so the method line on your report tells you which procedure was followed.
How point counting turns into a percentage
Point counting decides borderline results. A reticle (crosshair) is laid over the microscope field and the analyst scores only points that land on an asbestos fiber or on the surrounding matrix; empty points are not scored. Appendix E: "A total of 400 points superimposed on either asbestos fibers or nonasbestos matrix material must be counted over at least eight different preparations of representative subsamples," 50 points on each. The result is the share of points that landed on asbestos:
% asbestos = (a / n) × 100, where a is the number of asbestos counts and n is the number of nonempty points counted (400).
The appendix then fixes how to report: if a = 0, report "No asbestos detected"; if a is 1 to 3, report "<1% asbestos"; and "the value reported should be rounded to the nearest percent." In a 2007 applicability determination, EPA worked through what that rounding means at the regulatory line. The table follows that letter.
Asbestos points out of 400
Calculated
Reported
Above the "more than 1 percent" line?
0
0%
"No asbestos detected"
No
1 to 3
0.25% to 0.75%
"<1% asbestos"
No
4
1%
1%
No: EPA says this "does not meet the regulatory threshold of greater than 1 percent"
5
1.25%
"may be rounded down to 1 percent"
No, per EPA's 2007 letter
6
1.5%
"would be rounded to 2 percent"
Yes: "therefore regulated"
Source: Appendix E to 40 CFR 763 Subpart E, section 1.7.2.4 (eCFR, accessed November 7, 2026), and EPA applicability determination A070006, "Rounding Reported Values," January 31, 2007, as linked from NIST's NVLAP asbestos program page.
Why does it matter whether a lab estimated or counted? EPA's 1993 method says several studies "have each documented the tendency for visual estimates to be high when compared to point-count data." The NESHAP builds that in. Its definition of friable asbestos material says that if the asbestos content "is less than 10 percent as determined by a method other than point counting by polarized light microscopy (PLM), verify the asbestos content by point counting using PLM."
Reading the result: "none detected," "trace," "<1%" and layers
The low-result wordings are not interchangeable. NIST Handbook 150-3 (July 2025), the rulebook for accredited bulk labs, requires each lab to "have a working definition of trace and be able to distinguish between trace concentrations of asbestos and concentrations near 1 %." "Trace" means the analyst saw asbestos fibers but the concentration is "far from the level of 1 %." "Near to, but less than 1 %" is different: because of the uncertainty in the technique, "the analyst should recommend to the customer that verification of the results is necessary by a more accurate and precise method."
"None detected" has a floor too. EPA's 1993 method says PLM "can show significant bias leading to false negatives and false positives for certain types of materials". On floor tiles it says they "may contain fibers too small to be resolved by PLM (< 0.25 µm in diameter)." New York's lab certification program goes further for non-friable organically bound (NOB) materials such as floor tile and mastic. Its TEM method (ELAP Item 198.4, dated February 16, 2022) says it "is the only method that can be used to report true negative results from NOB samples to clients." That is a New York rule; elsewhere, ask the lab what it recommends for flooring.
Layers matter too: a wall sample can be paint, joint compound and wallboard, with only one layer positive. NIST's handbook says a lab "shall not composite the results for layered samples without reporting each individual layer as a separate sample" unless the report makes the deviation clear, and that "each individual layer must be analyzed and recorded." Expect a separate line, and often a separate charge, for each layer.
Under the same handbook, an accredited bulk lab's test report must include, among other items:
presence or absence of asbestos, and each asbestos type found;
the area percent of each type (or weight percent), "accompanied by an estimate of the error rate";
other fibrous materials and matrix materials, with their percentages, if known;
color and a macroscopic description of the sample;
whether the sample was inhomogeneous and whether parts were analyzed separately;
any problems or departures from the method, and an approved signatory's signature.
TEM and air clearance testing
The federal rules on air clearance come from the Asbestos Hazard Emergency Response Act (AHERA) rules for schools, 40 CFR 763 Subpart E. They do not apply to houses, but NVLAP's airborne TEM accreditation is built on them. Under 763.90(i), the main test for finishing a removal, encapsulation or enclosure project in a school is that the average of five air samples inside the work area, analyzed by TEM, is not statistically significantly different (by the rule's Z-test) from five samples taken outside it at the same time, with the three field blanks averaging below the filter background level of "70 structures per square millimeter." The rule also accepts five large-volume inside samples that average at or below that level. For projects larger than "small-scale, short-duration" but at or under 160 square feet or 260 linear feet, schools may use phase contrast microscopy (PCM) instead. An appendix to the same subpart states that EPA "recommends that transmission electron microscopy (TEM) be used for analysis of final air clearance samples" by NVLAP-accredited labs.
For homes, EPA's homeowner page says that after the work is complete, "an inspector or an independent air testing contractor may perform air monitoring to make sure there is no increase of asbestos fibers in the air."
What NVLAP accreditation means
NVLAP is the National Voluntary Laboratory Accreditation Program run by the National Institute of Standards and Technology (NIST). Its asbestos program page says it "provides assurance that laboratories are competent to analyze asbestos samples using polarized light microscopy (PLM) and/or transmission electron microscopy (TEM)," and that AHERA requires labs that analyze samples from public or private elementary and secondary schools to be NVLAP-accredited. No federal rule requires a homeowner to use one, but it is an outside check of a lab you do not know. Behind the certificate:
On-site assessment against ISO/IEC 17025, NIST Handbook 150 and Handbook 150-3.
Proficiency testing, which NIST says "is conducted biannually (twice a year) for PLM and annually (once a year) for TEM testing laboratories." All analysts must take part in every round; a lab that subcontracts the test "will be immediately suspended."
Failure has consequences. A lab that fails a round must document corrective action within 30 days and pass the next round or a retest to keep its accreditation.
NVLAP is not the only accreditor. When a Washington owner or employer wants to show that a presumed material is not asbestos, the state's rule accepts analysis by labs with "current successful participation in a nationally recognized testing program" such as NVLAP, the bulk-sample round robin run by the American Industrial Hygiene Association (AIHA), or an equivalent.
What the NVLAP list shows today
We fetched the directory (program "Asbestos Fiber Analysis," country United States) and each lab's scope document on November 7, 2026. Counts from our copy:
Measure
Count
How we counted
U.S. lab sites
213
One row per directory entry
Firms
170
Sites grouped by business name
Sites listing a bulk PLM method
212
Scope lists 18/A01 (Appendix E) or 18/A03 (EPA/600/R-93/116)
Sites listing airborne TEM
67
Scope lists 18/A02 (AHERA TEM)
States and territories with a site
38 states plus Puerto Rico
State on the directory entry
States with no site
12
Arkansas, Idaho, Iowa, Mississippi, Montana, Nebraska, New Mexico, North Dakota, Rhode Island, South Dakota, Vermont, Wyoming (also none in D.C.)
Sites the directory labels "Commercial Testing Service"
202
The directory's lab-type field; 8 are "Not Available for Commercial Testing" and 3 "Sometimes Avail. for Commercial Testing"
Airborne TEM sites are much scarcer than bulk labs: we counted them in 23 states, led by New York (15) and California (10). If a clearance plan calls for TEM, ask where the filters will be analyzed.
States with 10 or more NVLAP-accredited asbestos lab siteslab sites
Either type the lab's name or its NVLAP lab code (six digits, a hyphen and one or two more digits) in "Laboratory Name / NVLAP Lab Code," or choose Country "United States," your State, and Program "Asbestos Fiber Analysis."
Open the lab's entry and its scope of accreditation. Check that the scope lists the test you need: bulk (18/A01 or 18/A03) for building materials, airborne TEM (18/A02) for clearance air samples.
Check the accreditation period on the scope. On our November 7, 2026 copy, the expiry dates ran from December 31, 2026 to December 31, 2027.
Check the address: a firm with several branches can have an entry and code for each, so ask which site will analyze your sample.
The search page also links to "a list of laboratories with suspended or terminated accreditation."
The federal floor is low. EPA's homeowner page: "Federal law does not require persons who inspect, repair or remove asbestos-containing materials in detached single-family homes to be trained and accredited; however, some states and localities do require this."
The federal air rule, the asbestos NESHAP (40 CFR Part 61, Subpart M), requires a thorough inspection before demolition or renovation of a "facility." Its definition excludes "residential buildings having four or fewer dwelling units." EPA's overview adds that houses demolished or renovated "as part of a commercial or public project," such as an urban renewal or highway project, are not exempt. A building with five or more units is a facility.
States add their own rules. We read these four in the official text or the agency's own publication:
Jurisdiction (source, date)
Inspection or survey before work
Who may sample
Homeowner doing own work
Federal (EPA homeowner page, updated June 25, 2026; 40 CFR 61.141)
NESHAP inspection applies to facilities, not to residential buildings with four or fewer units (unless part of a commercial or public project)
No federal accreditation requirement for detached single-family homes; EPA recommends "a trained and accredited asbestos professional"
Not federally regulated; EPA: "Taking samples yourself is not recommended"
New York (12 NYCRR Part 56, sections 56-1.3 and 56-5.1; NYS DOL leaflets P229, P231, P232, dated 1/26; DOL Rule 56 guidance, version 2.0, 2009)
"an asbestos survey be performed prior to all interior and exterior renovation, remodeling, repair and demolition work"; DOL says surveys are required "regardless of construction date," or the building must be assumed to contain asbestos
"a certified New York State Asbestos Inspector"
Rule 56 "shall not apply to: (a) owner-occupied single family dwellings, where the owner performs the work." DOL's guidance says "This exemption is for ICR 56 in its entirety," which includes the survey section, and "If the owner hires a contractor to perform the work, then the exemption does not apply." DOL says the exemption covers only the occupied dwelling, not outbuildings, and a structure slated for demolition is not "occupied." DOL still recommends a licensed inspector for sampling
Colorado (Regulation 8, Part B, 5 CCR 1001-10, effective December 15, 2025; CDPHE asbestos guidance page)
Before renovation or demolition that may disturb more than the trigger levels of suspect material, it "must either be assumed to be ACM or must be inspected." Single-family trigger levels: 50 linear feet on pipes, 32 square feet on other surfaces or a 55-gallon drum. Buildings built after October 12, 1988 can be exempted on a division form. CDPHE says demolition needs a notification "even if no asbestos was found"
A Colorado-certified Building Inspector; CDPHE adds that the inspector "must work for a registered asbestos consulting firm"
Abatement certification rules "will not apply to any homeowner who performs asbestos abatement" on the single-family home that is their primary residence. Such a homeowner may also opt the home out of the rule's "area of public access" requirements, but not if they plan to demolish, sell or rent it. Ask CDPHE how this affects the inspection for your project
Washington (WAC 296-62-07721 and 07703, effective January 18, 2019)
Before authorizing construction, renovation, remodeling, repair or demolition, the owner must have "a good faith inspection" in a written report, unless the owner assumes the material contains asbestos and handles it under the rule, or is "reasonably certain that asbestos will not be disturbed by the project"
"The good faith inspection must be conducted by an accredited inspector"
The rule's definition of owner "does not include individuals who work on asbestos projects in their own single-family residences, no part of which is used for commercial purposes"
Texas (25 TAC § 296.1, effective July 8, 2021)
The state asbestos chapter "does not apply to a single private residence or a single apartment building with no more than four dwelling units," except a residential building subject to NESHAP
Not set by the state for those homes
Outside the state chapter for those homes; federal and local rules can still apply
In both New York and Washington the homeowner exemption is about doing the work yourself, not hiring someone. Rentals and flips can fall outside it: New York says corporations, contractors or "flippers" who will sell or rent the house "are not considered owners." Cities and counties can add permits. EPA's state asbestos contacts page (updated October 1, 2026) says your state department of environmental protection or health "will be the best place to address asbestos questions."
If you hire an inspector, EPA's checklist is short: "Make sure that the inspection will include a complete visual examination and the careful collection and laboratory analysis of samples." On removal: "It is better to use two different firms so there is no conflict of interest."
What sets the price and the turnaround
Few labs publish a per-sample price: when we checked the websites of 10 asbestos, lead and mold labs in November 2026, two showed one (only one of them, a test-kit seller, for asbestos), and three sites could not be read. We quote only figures a lab or agency printed itself. What changes the bill:
Number of samples and layers. One California lab's homeowner form says: "All pricing is per-sample, except for Asbestos PLM samples which are charged per-layer. Additional money may be owed for multi-layered PLM samples."
Turnaround. Faster costs more. On the form below, a one-hour PLM result costs more than twice the one-week price.
Material and method. On the form below, floor tile, mastic and roofing have their own, dearer test for non-friable organically bound (NOB) materials; outside New York the form also lets them go in as ordinary bulk PLM. In New York the form says NOB samples first run by PLM and found "<1% or Inconclusive" are "then required to be analyzed by Method 198.4 by TEM."
Who samples. A required inspector's visit and report come on top of the lab fee.
One published price list: the homeowner sample submittal form of LA Testing in South Pasadena, California (document COC-46-LAT, revision R16 dated November 7, 2024, downloaded November 7, 2026). Prices are per layer and are the lab's own; check the current form before sending.
Bulk NOB (floor tiles, mastic, roofing, caulking, cove base, vinyl molding); "PLM EPA NOB" outside New York
not listed
$160
$210
$370
$370 (24 hours)
Turnaround on that form "begins when the lab receives your sample(s)," so shipping time is extra.
Some states charge for the project itself. For single-family homes with asbestos above the trigger level but at or below 260 linear feet, 160 square feet or a 55-gallon drum, Colorado's CDPHE lists a $60 notice or permits of $180 (30 days), $300 (90 days) and $420 (one year). These are abatement fees, not testing fees, and Regulation 8 does not require the permit when homeowners do the work in their own primary residence or have opted out.
Before anyone samples: the official warnings
We do not judge whether a material in your home is safe to touch. The agencies' own words:
EPA, Protect Your Family from Exposures to Asbestos (updated June 25, 2026): "A trained and accredited asbestos professional should take samples for analysis, since a professional knows what to look for, and because there may be an increased health risk if fibers are released. In fact, if done incorrectly, sampling can be more hazardous than leaving the material alone. Taking samples yourself is not recommended."
EPA lists what releases fibers: asbestos-containing materials "may release fibers when they are disturbed, damaged, removed improperly, repaired, cut, torn, sanded, sawed, drilled or scraped." Its don'ts include "Don't dust, sweep, or vacuum debris that may contain asbestos."
New York's Department of Labor names materials it treats as assumed asbestos from their history: "White heating system pipe wrap insulation," "9-inch x 9-inch floor tiles," "Transite (cement) siding" and "Vermiculite attic insulation." It adds: "the only certain way to determine the asbestos content of materials is by sampling and analysis."
And the reassurance from the same EPA page: "If you think there may be asbestos in your home, don't panic. Asbestos-containing materials that aren't damaged or disturbed are not likely to pose a health risk."
Popcorn ceilings and mail-in kits
A textured ceiling sample is a bulk PLM sample like any other, often with paint layers over the texture; our guide to testing a popcorn ceiling for asbestos covers it. If a test kit sends your sample to a lab, the questions above apply to that lab; our guide to asbestos test kits versus lab testing compares the options. Where your state requires a certified inspector before renovation, a kit does not replace that inspection.
Asbestos in water is a separate test
EPA's drinking water table sets a maximum contaminant level of 7 million fibers per liter (MFL) for asbestos fibers longer than 10 micrometers. EPA lists the potential health effect as "Increased risk of developing benign intestinal polyps" and the common sources as "Decay of asbestos cement in water mains; erosion of natural deposits." That limit applies to public water systems, not private wells. The same California lab form lists it as a separate test (EPA Method 100.2), with samples "submitted on ice." To check a well, ask a state-certified drinking-water lab whether it is certified for asbestos. See also which tests to order.
Health effects: what the agencies say
EPA's asbestos overview (updated July 13, 2026) says: "Exposure to asbestos increases your risk of developing lung disease. That risk is made worse by smoking." It adds that "Disease symptoms may take many years to develop following exposure" and names three of the major health effects: lung cancer; mesothelioma, "a rare form of cancer that is found in the thin lining of the lung, chest and the abdomen and heart"; and asbestosis, "a serious progressive, long-term, non-cancer disease of the lungs."
The National Cancer Institute's fact sheet (reviewed May 20, 2021) says asbestos is classified as a known human carcinogen by HHS, EPA and the International Agency for Research on Cancer (IARC), and that per IARC there is sufficient evidence it causes mesothelioma and cancers of the lung, larynx and ovary. It says it "can take from 10 to 40 years or more for symptoms of an asbestos-related condition to appear." NCI advises people who have been, or suspect they have been, exposed to "inform their doctor about their exposure history and whether or not they experience any symptoms." A material test says nothing about your own health; questions about a past exposure belong with your doctor.
A short checklist before you order a test
Decide whether you need one. EPA says undamaged material that will not be disturbed does not need testing, and that you may want an inspection if you plan to remodel or have damaged building materials.
Check your state's rule. If it requires a certified or licensed inspector, hire one.
Pick an accredited lab for the right test (bulk PLM or TEM air) and check its scope and expiry.
Ask the lab whether it accepts homeowner samples, how it charges for layers, whether it point counts results near 1 percent, and what it recommends for flooring; then read the report's type, percent per layer, method and any note recommending another method.
Few labs publish prices. One California lab's homeowner form (revision dated November 7, 2024) lists bulk PLM analysis at $95 per layer for two-week turnaround, $130 for one week and $165 for 24 hours, with floor tile and mastic priced separately at $160 to $370. That form charges PLM per layer and says "Additional money may be owed for multi-layered PLM samples," so a three-layer wall sample can cost three times the single-layer price. A required inspector's visit is extra.
Can I take an asbestos sample myself?
EPA says: "Taking samples yourself is not recommended," because "if done incorrectly, sampling can be more hazardous than leaving the material alone." Federal law does not require accreditation for work in detached single-family homes, but some states do. New York requires a survey by a certified state asbestos inspector before renovation, except in an owner-occupied single-family home where the owner does the work. Colorado requires a certified inspector, or treating the material as asbestos, before work disturbs more than its trigger amounts; homeowners living in a single-family home can opt out of some requirements, so ask CDPHE. Check your state's rule first.
What does "<1%" or "trace" mean on an asbestos report?
Under the federal point-count method, a lab counts 400 points; 1 to 3 points on asbestos are reported as "<1% asbestos." NIST's handbook for accredited labs says "trace" means fibers were seen but the level is "far from the level of 1 %," while a result near but below 1 percent should come with a recommendation to verify it "by a more accurate and precise method." Ask the lab which applies.
How long do asbestos test results take?
It depends on the turnaround you pay for. One California lab's homeowner form offers bulk PLM results from one hour to two weeks, priced higher for faster service, and says turnaround "begins when the lab receives your sample(s)," so shipping time is extra. The form's separate floor tile and mastic (NOB) test starts at 24 hours. TEM air clearance labs are fewer: we counted them in 23 states.
Do I need an NVLAP-accredited lab?
No federal rule requires a homeowner to use one; AHERA requires NVLAP accreditation for labs analyzing school samples. Accreditation means on-site assessment and proficiency testing twice a year for PLM labs. Some states accept other programs: Washington's rule names NVLAP and the AIHA bulk round robin. Check the lab's scope and expiry date in the NIST directory before sending samples.
Does a negative floor tile result mean there is no asbestos?
Not always. EPA's 1993 bulk method says floor tiles "may contain fibers too small to be resolved by PLM," and New York's lab rules say TEM "is the only method that can be used to report true negative results" for non-friable organically bound materials such as floor tile and mastic. Ask the lab whether it recommends a second method for your flooring sample.
Is there an accredited asbestos lab near me?
On November 7, 2026 the NIST NVLAP directory listed 213 U.S. lab sites in 38 states and Puerto Rico; 12 states had none. Our list above groups them by state. The directory does not say which labs accept samples from homeowners or by mail, so ask the lab before sending anything.