NIOSH Explains How to Test Stockpiled Respirators

A new NIOSH Science Bulletin outlines sampling and lab testing methods for respirators held in emergency stockpiles.

Updated on Nov. 9, 2026 in Asthma

Bold flat-color editorial illustration of stacked plain cartons on a pallet beside a sealed sample bag holding a respirator, in navy and cream. — NIOSH issued a Science Bulletin on November 5, 2026, detailing how to sample, inspect, and lab-test respirators held in emergency stockpiles. AI Illustration. Upload story photo >

The National Institute for Occupational Safety and Health issued a Science Bulletin dated November 5, 2026, describing how to sample and test stockpiled respirators. The guidance covers how to select units, inspect them visually, and send them to accredited labs.

Why it matters

Respirator materials break down with age, so stockpile managers need a way to confirm whether units still provide protection. Makers often set shelf-life limits and storage conditions, and outside those limits they cannot promise expected protection.

The stockpile model draws 40 respirators at random per production lot, with each unit tested at 85 liters per minute against a 25 mm H2O exhalation limit and a 35 mm H2O inhalation limit. Passing lab tests does not make a respirator NIOSH Approved once its shelf life has ended.

The players

National Institute for Occupational Safety and Health (NIOSH)

NIOSH is the federal agency within the Centers for Disease Control and Prevention responsible for research and guidance on occupational safety and health, including respirator certification.

The details

NIOSH recommends that every pallet, case, box and unit receive a visual check during collection, watching for heavy dust, light exposure, nearby chemicals and crushed packaging. Testing must be run by third-party labs accredited for filter efficiency, inhalation resistance and exhalation resistance, following NIOSH Standard Test Procedures for N95 filtering facepiece respirators.

November 5, 2026: NIOSH issued the Science Bulletin on respirator stockpile testing.
November 9, 2026: The article was published on ohsonline.com.

Health Landscape

The bulletin extends the NIOSH N95 certification program from initial approval into long-term storage, a stage where certified respirators can degrade. It applies the program's Standard Test Procedures to stockpiled units rather than newly manufactured ones.

People who rely on stockpiled respirators for workplace or emergency use should check packaging for dust, light exposure or crushing before use. Units past their shelf life may not provide the protection listed on the label.

The takeaway

Stored respirators should be checked against their shelf-life and storage limits rather than assumed to remain effective. Testing through accredited labs is the step that confirms whether a unit still meets NIOSH performance thresholds.