Disposable Glove Quality Testing

The FDA sets high standards to ensure the disposable gloves you purchase here in the U.S. perform as expected and provide an adequate barrier for their intended use.  To meet these standards, glove manufacturers have tight quality controls and manufacture gloves according to ASTM specifications and testing requirements.

A key quality measurement that glove manufacturers publish on glove boxes, bags and product literature is AQL, or Acceptable Quality Level.

Stated as a percentage, the AQL is a statistical measurement of the quality of the gloves.  An AQL of 2.5% means that statistically, only 2.5 gloves for every hundred gloves will fail a quality test.

How AQL is Determined

Let’s say a glove manufacturer produces 10,000 gloves from the same material, settings and processes.  Two hundred gloves would be pulled randomly from the line, throughout the batch, to be tested.  To meet an AQL of 2.5%, no more than 10 gloves can fail the quality tests.  If more than 10 gloves fail, the entire batch fails, and each glove must be tested individually for quality, or else the whole batch is discarded.  An AQL of 1.5% would mean that no more than 7 gloves could fail.

ASTM D5151 Test for Detection of Holes in Medical Gloves

Disposable gloves are subjected to numerous ASTM tests throughout the manufacturing process.  One test that medical and cleanroom gloves have in common is a test for pinholes.

ASTM D5151 is the Standard Test Method for Detection of Holes in Medical Gloves, often referred to as the “watertight” test or “water leak” test.   In this test, the gloves are each filled with 1000 ml of water at room temperature, secured at the cuff and hung vertically for two minutes to check for pinholes.  If water does not leak from the glove, it gets a “pass.”

The current FDA mandated maximum AQL for examination and cleanroom gloves on this test is 2.5%, down from the previous 4.0% prior to December 2008.  Some gloves, however, are manufactured and tested to meet the lower AQL of 1.5% required for surgical gloves.  This means higher quality and fewer pinholes.

What is Nitrile Anyway?

Disposable nitrile gloves have become a mainstay in the medical, dental, lab, cleanroom and food handling industries.  We enjoy their strong, latex-free comfort.  But what is nitrile anyway?

The Science of Nitrile

Nitrile is a shortened term for Nitrile Butadiene Rubber, or NBR.  Although it is also referred to as NBR latex, there is no natural rubber latex (or latex proteins) in the material.  Nitrile is a synthetic rubber copolymer of acrylonitrile and butadiene.  These two materials (monomers) are placed in a stainless steel vat, and using hot or cold polymerization, a chemical reaction occurs, and voila!  Nitrile is born.

The nitrile latex is filtered and blended with an antioxidant to stabilize the material.  Next, the liquid is solidified by adding coagulating agents, then finally washed and dried.  The resulting material is referred to as “crumb rubber.”  Crumb rubber can be liquefied by product manufacturers to make nitrile rubber materials, such as floor mats, footwear, adhesives and gloves.

Low-Modulus Magic

Nitrile alone, without anything added, is a fairly rigid material.  So glove manufacturers add a small percentage other chemicals to NBR in order to create a soft, or low modulus, nitrile glove.  Over the past decade, these manufacturers have continued to improve their nitrile glove material formulations.  Disposable nitrile gloves have grown softer and more elastic.  The latest innovations in nitrile glove development include accelerator-free formulations that lower the risk of Type IV contact dermatitis in wearers.

These thin and flexible gloves are what we have all come to rely on to keep ourselves, our patients, products and food items safe.  Nitrile gloves are more resistant to oils and acids than natural rubber (latex) gloves.  The material is resistant to abrasion and puncture, making it suitably durable for many tasks.  Low modulus nitrile gloves also conform well to the hand and provide excellent tactile sensitivity.

As disposable nitrile glove formulations evolve, hand protection is becoming ever safer and more comfortable.  We look forward to continuing to bring you the very best nitrile gloves made from the latest materials.

Have you noticed the improvements in disposable nitrile gloves over the years?  We’d love to hear your comments.  Share them with us below!

HandPRO Gloves Get a Fresh, New Website

For most companies, each new year brings exciting opportunities to overcome challenges, launch new products and improve communication with customers and distribution partners.

We’re no different, and this year we are starting off right with a fresh, new website.

The new www.HourglassIndustries.com brings you new information and new features, all designed to improve your experience.

Read moreHandPRO Gloves Get a Fresh, New Website

Protective Gloves Are Critical to Worker Safety in Hurricane Flooded Areas

Now that a hurricane and a tropical storm have completed their runs up the East Coast, the clean up begins. But it’s not as simple as rolling up your sleeves and grabbing a push broom to move out the muck. Flood waters are usually contaminated and present real health and safety concerns. It is imperative that rescue workers, emergency personnel and clean-up crews give careful attention to hand hygiene and wear protective gloves.

Read moreProtective Gloves Are Critical to Worker Safety in Hurricane Flooded Areas

Powdered and Latex Medical Gloves to Be Banned?

Almost everyone in the glove industry heard the news back in April. Public Citizen, a consumer advocacy group, petitioned the FDA to take drastic steps to protect individuals with latex allergies. They called for a complete ban on all cornstarch powdered medical gloves, as well as a ban on all natural latex rubber medical gloves.

Read morePowdered and Latex Medical Gloves to Be Banned?

Accelerator-Free Nitrile Exam Gloves – A Better Alternative

As hospitals and other healthcare facilities have increasingly moved from latex exam gloves to nitrile exam gloves, skin irritation and allergy to non-latex gloves has also increased. To identify individuals with hypersensitivity to nitrile gloves, a new skin prick test has been developed by Dr. Santhosh Kumar of Virginia Commonwealth University, Richmond. “If the patient is positive,” says, Dr. Kumar, “we tell them to avoid nitrile gloves,” and he recommends vinyl gloves as an option.

Read moreAccelerator-Free Nitrile Exam Gloves – A Better Alternative

FDA Soon to Require Warning Label on Powdered Medical Gloves


UPDATE:  The “Draft Guidance for Industry and FDA Staff – Recommended Warning for Surgeon’s Gloves and Patient Examination Gloves that Use Powder,” referenced in this post, was withdrawn on April 27, 2015.


The problems associated with powdered medical gloves are well documented. The FDA first issued a Medical Glove Powder Report back in 1997, warning of adverse health events that included dyspnea, respiratory problems, allergic reactions, and granuloma formations.

Read moreFDA Soon to Require Warning Label on Powdered Medical Gloves

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