Technical

Meta-aramid

An aromatic polyamide with a different molecular arrangement from para-aramid, used for thermal performance..

Reviewed 2026-09-22. Evidence level: verified. Open the interactive profile.

Key figures

Polymer: poly(m-phenylene isophthalamide), MPIA or PMIA
US generic name: aramid (16 CFR 303.7)
Melting behavior: chars and decomposes rather than melting
Spinning route: wet or dry spinning from amide solvent, then hot drawing
Nomex owner: Arclin, since 1 April 2026

Approximate values under the stated conditions.

Overview

An aromatic polyamide with a different molecular arrangement from para-aramid, used for thermal performance.

Feel and behavior

Technical fiber chosen for heat-related applications.

Where you find it

Protective garments, filtration and electrical insulation.

Source and geography

Meta-aramid is the aromatic polyamide poly(m-phenylene isophthalamide), abbreviated MPIA or PMIA, made from m-phenylenediamine and isophthaloyl chloride, both petrochemical intermediates. It is produced by specialist manufacturers as staple, filament, fibrids and paper. Nomex, created by DuPont, has belonged to Arclin since 1 April 2026, when DuPont's Aramids business changed hands. End uses include flame-resistant clothing, hot-gas filtration, electrical insulation paper, honeycomb cores and, increasingly, membranes.

Advantages

Its flame resistance is inherent to the polymer, so it does not wash out.
It does not melt or drip onto skin, and it chars into an insulating layer.
It holds useful strength at elevated temperatures and resists many chemicals.
Blends with a little para-aramid resist break-open after charring.

Drawbacks

It is expensive compared with treated cotton flame-resistant fabrics.
It shrinks and becomes brittle once charred, so a garment exposed to fire must be retired.
Ultraviolet light fades and weakens it, especially in light colors.
A single layer gives limited arc protection, so high-energy work needs heavier multilayer systems.

Worth knowing

The Nomex IIIA blend includes 2 percent carbon-based antistatic fiber, a small component that addresses static ignition risk around flammable vapors.
NFPA 2112 requires fabrics to pass the vertical flame test again after 100 launderings, not just when new.
NFPA 70E's PPE categories stop at 40 cal/cm2, and work at higher incident energies is generally approached by de-energizing equipment rather than by heavier clothing.

Types, grades and fabrics

Types and grades

Meta-aramid is sold as staple for spinning, as filament, as short-cut fibers and film-like fibrids for paper, and as dope-dyed or producer-colored fiber because the finished fiber dyes poorly. In apparel the best-known blend is Nomex IIIA, which the producer describes as 93 percent Nomex, 5 percent Kevlar and 2 percent antistatic fiber: the para-aramid reduces break-open when the fabric chars, and the carbon-based antistatic fiber limits static sparks. Other blends pair meta-aramid with flame-resistant viscose or modacrylic for softness. Workwear fabrics are sold by weight, for example 4.5 oz per square yard for light coveralls, with heavier multilayer systems for higher arc ratings.

Fabrics and products

Woven twills and plain weaves make flame-resistant shirts, trousers and coveralls for refineries, utilities and chemical plants; flight suits and racing suits use similar fabrics. Knits make hoods, balaclavas and underlayers. Firefighter station wear and turnout gear use meta-aramid in outer shells, moisture barrier substrates and thermal liners. Multilayer arc flash suits combine several fabric layers to reach higher arc ratings. Industrial forms include hot-gas filter felts, sewing thread for flame-resistant seams, and calendered paper for electrical insulation and honeycomb cores.

Buying and care

How to judge quality

Look for the standard and the numbers on the garment label. NFPA 2112 covers flash fire: fabrics must, among other tests, keep predicted body burn at 50 percent or less on an instrumented manikin in a 3-second flash fire (ASTM F1930) and char no more than 4 inches (100 mm) in the vertical flame test, initially and after 100 launderings. NFPA 70E covers electrical arc flash: garments carry an arc rating (ATPV or EBT) in cal/cm2, and PPE categories 1 to 4 require at least 4, 8, 25 and 40 cal/cm2. A 2112 label does not imply an arc rating, or the reverse. Red flags are 'FR' claims without a standard, and 'Nomex' used loosely for unlabeled blends.

Care in detail

Follow the garment label, which governs. Many meta-aramid garments can be home washed warm with an ordinary detergent, turned inside out; makers generally advise against chlorine bleach for aramid. Remove oil, grease and solvent soils promptly or send the garment to an industrial launderer, because flammable contaminants can burn even when the fabric does not. Tumble dry at moderate heat and remove promptly. Repair only with flame-resistant thread and matching fabric, and never add non-FR patches. Retire garments that are charred, thin, torn, heavily contaminated or past the maker's service guidance.

Care at a glance

Use the manufacturer’s application-specific maintenance and handling instructions. Technical performance cannot be inferred from household laundry guidance.

Environmental and social footprint

Meta-aramid is made from petrochemical monomers and spun from amide solvents that must be recovered, and like other aramids it is not biodegradable. Its environmental case rests on durability and inherent flame resistance: no flame-retardant finish is applied, so none is lost in laundering, and garments can last for many wash cycles. The atlas found no independent per-kilogram life cycle figures to cite. At end of life, contaminated protective clothing is usually landfilled or incinerated; recycled content claims for protective fabrics should be documented. Industrial laundering of oil-soiled garments also creates wastewater that must be treated.

Tradeoffs

Evaluate the specified grade, whole product, useful lifetime and realistic recovery route. A technical property does not establish a lower overall impact.

A useful question to ask: What exact material, product form and documented producer stand behind this name?

Science

Data sheet

Property	Value	Conditions	Source
Density	1.38 g/cm3	Nomex fiber, museum conservation reference	[1]
Moisture regain	3.5 %	Nomex fiber, museum conservation reference	[1]
Tenacity	about 47 cN/tex	dry; converted from 5.3 g/den (Nomex fiber)	[1]
Elongation at break	22 %	Nomex fiber, museum conservation reference	[1]

Application-specific engineered material

Read the exact polymer, precursor and grade before comparing performance.

Structure and chemistry

In MPIA the benzene rings are joined through amide groups at their meta (1,3) positions, which puts a bend into every repeat unit. The kinked chain cannot form a liquid-crystalline dope, so orientation and modulus stay far below those of para-aramid, and the fiber behaves more like a textile fiber, with useful elongation and a soft hand. Dense hydrogen bonding and aromatic rings still give a very high glass transition and thermal stability, and the polymer decomposes before it melts. Fibers are usually round and smooth. The same polymer also forms porous hollow-fiber ultrafiltration membranes by phase inversion.

From source to yarn

Polycondensation of m-phenylenediamine with isophthaloyl chloride in a polar amide solvent gives a polymer solution that is neutralized to remove hydrogen chloride. The dope is spun by wet or dry spinning, then washed, hot-drawn and crystallized; research on porous MPIA fibers shows that hot drawing raises strength by reducing structural defects. Staple is blended, often with a small share of para-aramid and antistatic fiber, spun into yarn and woven or knitted into flame-resistant fabric. For paper, short fibers and film-like fibrids are formed into sheets and calendered, and recent work combines MPIA fibers with aramid nanofibers to improve tear strength of insulating paper.

Performance in use

Meta-aramid is chosen for heat and flame behavior. It does not melt or drip, self-extinguishes when the ignition source is removed, and when strongly heated it chars and thickens into an insulating layer. It keeps useful strength at elevated temperatures and resists many chemicals, which suits hot-gas filter bags. Tenacity and modulus are much lower than para-aramid. It is difficult to dye and is often producer-colored, and ultraviolet exposure causes yellowing and strength loss. Blends with modacrylic, flame-resistant viscose or carbonized fibers are used in firefighter station wear to balance flame behavior with comfort.

How it is identified

Burn tests are indicative only and never a substitute for standard flame tests: meta-aramid chars and shrinks without melting or dripping and stops burning once removed from the flame. Microscopy shows smooth, round fibers without the pronounced fibrillation of para-aramid. FTIR distinguishes meta- from para-aramid and from flame-resistant viscose or modacrylic. Nomex is often used loosely for any flame-resistant garment, so blend composition should be checked.

History

Timeline

1967DuPont first marketed Nomex, a meta-aramid developed in the early 1960s, which became a reference fiber for flame-resistant clothing. [2]
2025DuPont agreed on 29 August to sell its Aramids business, including Nomex, to Arclin. [3]
2026Arclin completed the acquisition on 1 April, taking ownership of the Nomex brand. [4]

Meta-aramids expanded the use of synthetic fibers in demanding thermal environments. Protection depends on a tested fabric or system, not the fiber name alone.

The deeper record

Meta-aramid came out of DuPont research on high-temperature aromatic polyamides and became a cornerstone of flame-resistant clothing for firefighters, military aircrew, racing drivers and industrial workers, and of insulation paper for electrical equipment. Its uses have since widened into hot-gas filtration, porous fibers loaded with activated carbon for breathable chemical-protective clothing, and ultrafiltration membranes. Ownership of the leading brand changed when DuPont agreed on 29 August 2025 to sell its Aramids business to Arclin, a deal completed on 1 April 2026.

Labeling and law

In the United States, meta-aramid is labeled with the generic name aramid under 16 CFR 303.7, whose definition requires at least 85 percent of amide linkages attached directly to two aromatic rings; EU labels use aramid under Regulation (EU) No 1007/2011. Nomex is a trademark. Flame-resistant garments are judged against product-specific performance standards independent of fiber labeling, so compliance should be confirmed from test certificates for the exact fabric and garment.

This describes what rules and standards cover. It is not legal advice; jurisdiction, product form and current rule text control.

Frequently asked

Is Nomex fireproof?

No fabric is fireproof. Meta-aramid is flame resistant: it resists ignition, self-extinguishes when the flame is removed and does not melt, which buys escape time. Under prolonged exposure it chars, shrinks and eventually breaks open, and heat still passes through to the skin.

What is the difference between NFPA 2112 and NFPA 70E?

NFPA 2112 sets requirements for flame-resistant garments that protect industrial workers against flash fire, a short hydrocarbon fireball. NFPA 70E is an electrical safety standard that uses arc ratings in cal/cm2 to match clothing to arc flash hazards. A garment can meet one without the other.

What does an arc rating of 8 cal/cm2 mean?

It is the incident energy at which the fabric or system has a 50 percent probability of letting enough heat through to cause the onset of a second-degree burn. An 8 cal/cm2 garment meets the minimum for NFPA 70E PPE category 2.

Can I wear a polyester T-shirt under FR clothing?

Safety guidance generally says no: meltable synthetics under flame-resistant clothing can melt and stick to skin if the outer layer is breached or heated. Nonmelting fibers such as cotton, wool or FR underlayers are the usual choice. Your employer's hazard assessment governs.

Sources

Cite this page

Chaos. (2026). Meta-aramid. In Fibers of Earth: An independent textile atlas. https://www.hendrickresearch.com/fibers/materials/meta-aramid/