Those who wear a respirator on the job, safety leaders, industrial hygienists, and supervisors, need both seal checks and respirator fit tests. If you are responsible for keeping people safe around airborne hazards, this information will help you explain to workers what to do and why it matters.

The Short Answer

A user seal check is a quick self-check every time the respirator is puton. A fit test is a formal, documented evaluation to confirm a specific make, model, and size can seal on a specific person. You need both. One verifies today’s seal. The other determines whether the respirator is a good match for the wearer in the first place.

Why People Get This Wrong

Pass a fit test once, and it can feel like the work is done. It is not. Faces change. Donning technique slips. Straps wear. A user seal check catches those day-to-day variables before someone steps into a hazardous space. Fit testing makes sure the correct apparatus and training is applied and properly used.

What Is a User Seal Check?

• A seal check is a quick check by the wearer each time the respirator is donned and after any adjustment or break.
• The goal is to confirm the facepiece is seated and sealed correctly for the current usage.
• Methods depend on the respirator, but commonly include both a negative pressure check (by covering inlets and gently inhaling to feel inward collapse and no leaks) and a positive pressure check (by exhaling gently while covering the exhalation path and confirming no outward leakage).
• Self checks are not a fit test, do not provide a numeric fit factor, and are technique dependent. They require training.

What Is A Fit Test?

• A fit test is a structured procedure to determine if a specific respirator model and size can achieve an adequate seal on a specific person.
• Two approaches to fit testing: Qualitative fit testing provides pass or fail outcomes, and quantitative fit testing uses an instrument to measure a fit factor.
• When fit testing is required: Before first required use, at least annually, and whenever something could change the fit such as new model or size, significant weight change, facial surgery, dental work, scars, or changes in other personal protective equipment that interfaces with the facepiece seal.

How These Two Work Together

• The fit test selects the right respirator and documents that it can seal on that person.
• The user seal check verifies that today’s usage and conditions still produce a good seal.
• Training connects the two so workers can don the device correctly, perform checks properly, and recognize when something is wrong.

Step-By-Step User Seal Check Guide

1. Start clean-shaven wherever the respirator seals to the face.
2. Inspect the facepiece, valves, cartridges or filters, and straps.
3. Don the respirator following the manufacturer’s sequence and set even strap tension without over-tightening.
4. Perform a negative pressure check by covering the inlets and inhaling gently, and hold for several seconds while feeling for collapse and no leaks.
5. If applicable, perform a positive pressure check by covering the exhalation path and exhaling gently and confirm no outward leakage.
6. If leakage is felt, reseat the respirator and repeat the checks. Notify the supervisor or program administrator if leakage persists.

Everyday Reasons A Good Fit Can Turn Into A Bad Seal

• Facial hair or even short stubble in the seal zone
• New eyeglasses with thick temples or other PPE that interferes with the seal
• Lotions, heavy makeup, sweat, or rain on the seal area
• Weight change or swelling
• Strap creep during the shift or worn components

Quick Troubleshooting For Common Seal Check Failures

• Stubble in the seal zone: Require a clean shave where the seal contacts the skin.
• Uneven or misplaced straps: Retrain on donning sequence and strap placement.
• Wrong size or shape: Call FACS for fit testing.
• Damaged parts: Replace valves, straps, and worn filters per manufacturer guidance.

Program Elements That Make Both Succeed

• A written respiratory protection program with clear roles and procedures
• Initial and annual fit testing plus change-triggered retesting
• Hands on training with demonstration of donning, user seal checks, limitations, and maintenance
• Cleaning, storage, and replacement schedules
• Recordkeeping for fit tests, training, medical clearance, and equipment inventories
• Field verification by supervisors early in the shift to reinforce correct behavior

Supervisor Checklist For The Start Of Shift

• Confirm clean shave status in the seal area.
• Observe donning and user seal checks for a sample of workers.
• Watch for PPE conflicts such as eyewear.
• Replace worn parts promptly.
• Escalate to the program administrator if seal check failures occur.

Fit Testing Frequently Asked Questions

• Do user seal checks replace fit tests? No. Both are required for tight fitting respirators used for protection.
• How long should a user seal check take? Under a minute when trained.
• What if a worker cannot achieve a seal? Try a different respirator of the same type. Contact FACS for advice on a fitting option that provides the needed protection.
• How often should users be retrained? At least annually and whenever deficiencies are observed or changes occur.

The Bottom Line

A fit test proves the respirator can fit the person. A user seal check proves the respirator does fit today. Build both into daily practice, and you reduce risk, improve comfort and compliance, and keep your program audit ready.

FACS provides on-site qualitative and quantitative fit testing, program development, and user training. If you need help or have questions, contact FACS to schedule a consultation.

Call us at (888) 711-9998 or contact us online here: https://facs.com/contact-us/.