Moldex 6840 Mellows Corded Earplugs NRR 30 100 Pairs Review (2026)

Is the Moldex 6840 the Right Corded Earplug for Your Job Site?

Moldex 6840 Mellows Corded Earplugs NRR 30 100 Pairs Review (2026)

When your noise exposure sits between 85 and 100 dBA and you need a plug that won't punish workers who forget where they set it, a corded disposable earplug is often the right answer. The Moldex 6840 Mellows threads that needle: NRR 30 roll-down foam, a connecting cord to keep pairs together, and Moldex's ultra-soft polyurethane formula that reduces the pressure buildup workers complain about after four-hour stretches. This review covers the 100-pair corded bag — the format most safety managers reach for when running a mid-size operation.

Moldex built its reputation on latex-free, PVC-free foam, and the Mellows series is no exception. The 6840 shares the same foam compound as the uncorded 6820, adding only the cord for retention. That makes compliance easier: workers can hang the pair around their neck during brief quiet periods instead of pocketing them or losing them on a bench. For programs governed by OSHA 29 CFR 1910.95, reducing plug loss directly supports TWA compliance.

Below you will find every verifiable spec, a direct comparison against competing NRR 30 corded plugs, honest weaknesses, the complete Mellows family lineup, and a plain-English guide to calculating whether NRR 30 is actually adequate for your exposure levels — all without inflated claims or manufacturer copy-paste.

Who the Moldex 6840 Is Best For

The 6840 is the right plug when your noise exposure TWA falls between 85 and 97 dBA and cord retention is a priority. It fits manufacturing floors, assembly operations, construction staging areas, utilities maintenance, and any environment where workers move between loud zones and quiet spaces repeatedly per shift. The cord keeps the plug accessible during short breaks without pocketing — a real compliance lever when supervisors can't monitor every worker at every moment.

Workers with latex sensitivities can wear it without concern. The PVC-free foam also aligns with programs that restrict certain plasticizers in skin-contact PPE. If your site runs an NRR-based hearing conservation program, the 6840's NRR 30 rating will satisfy most moderate-exposure job classifications without over-attenuating to the point of masking important communication or equipment signals.

For high-noise environments above 100 dBA TWA, look at NRR 33 options like the Moldex 6800 series or double-protection protocols. For workers who object to roll-down foam, banded earplugs or pre-molded plugs may suit better. Browse the full earplug collection for alternative formats.

Strengths of the Moldex 6840

NRR 30: Calibrated for the Most Common Industrial Exposures

NRR 30 is not the maximum rating on the market, but it is the right rating for a large proportion of American industrial workplaces. OSHA's permissible exposure limit is 90 dBA TWA (8-hour), with the action level at 85 dBA. Using OSHA's 50% derating method — which OSHA recommends for all roll-down foam plugs — the 6840's real-world attenuation is approximately 11.5 dB. That means a worker in a 96.5 dBA TWA environment effectively receives a corrected exposure of 85 dBA, sitting right at the action level threshold.

For exposures measured at 85–97 dBA, the 6840 is adequately protective under OSHA 29 CFR 1910.95 without over-attenuating — which matters on worksites where workers need to hear verbal warnings, forklift signals, or equipment alarms. Over-protection creates its own hazard; the 6840 avoids it. Review our NRR hearing protection guide for the full derating methodology.

Ultra-Soft Polyurethane Foam: Sustained Wear Comfort

Moldex's foam compound in the Mellows series is notably softer than standard polyurethane plugs. Standard roll-down foam creates pressure as it re-expands in the canal. Extended-wear programs — 10- and 12-hour shifts — frequently see compliance drop because workers remove plugs during the back half of shifts to relieve that pressure. The Mellows foam is engineered to expand more slowly and exert less outward force, which maintains a good acoustic seal without the discomfort that drives premature removal.

This is a documented safety advantage, not a comfort luxury. If your program struggles with compliance on long shifts, a softer foam earplug can recover hours of effective protection per day per worker. See our guide on best foam earplugs for a broader comparison across foam formulations, and our best earplugs for work roundup for use-case-specific recommendations.

Cord Retention: Real Compliance Impact

The cord on the 6840 is its most operationally meaningful differentiator from the 6820. In practice, workers hang the corded pair around their neck during brief quiet periods — equipment changeovers, supervision check-ins, quick conversations. Without a cord, plugs typically go into a pocket (contaminated) or a bench (lost). Either outcome removes the plug from the rotation and creates a replacement cost and a compliance gap.

A 100-pair corded bag at $56.07 represents a per-pair cost of roughly $0.56. Lost uncorded plugs frequently drive per-shift consumption above 1 pair per worker. Cord retention alone can pay back the modest premium over uncorded formats within weeks on a sizable crew. For a deeper look at how cord and banded designs compare across use cases, see our reusable vs. disposable earplugs guide.

Latex-Free and PVC-Free: No Material Exclusions

A meaningful share of the workforce has latex sensitivity, ranging from contact dermatitis to more serious reactions. Latex-containing earplugs require program administrators to either screen workers or maintain a separate plug inventory. The 6840's latex-free and PVC-free construction eliminates that bifurcation — every worker on the line wears the same plug, simplifying procurement and inventory. It also aligns with OSHA's general duty to avoid known sensitizers in PPE when alternatives are equally effective.

100-Pair Corded Bag: Program-Scale Quantity

The 6840 ships in 100-pair bags, which is the standard procurement unit for mid-size hearing conservation programs. It is large enough to stock a supply cabinet for a four- to eight-week cycle on a small crew but small enough to avoid the waste risk of oversized bulk orders on jobs with variable headcount. For facilities running the Moldex PlugStation system, the same Mellows foam is available in 250-pair (6846) and 500-pair (6847) dispenser-ready formats. Browse all hearing protection options for complementary products.

Weaknesses of the Moldex 6840

Roll-Down Insertion: Training Is Not Optional

Every roll-down foam earplug is only as effective as its insertion. NIOSH fit-testing data consistently shows that improper insertion reduces real-world attenuation well below the labeled NRR — in some cases below NRR 10. The 6840's NRR 30 assumes the plug is correctly rolled, the ear canal is pulled up and back, and the plug is held in place while it fully expands. Workers who rush the process or skip the ear-pull step create a marginal seal that provides far less protection than the program assumes.

This is not a Moldex-specific weakness — it applies to all roll-down foam. But it is a real limitation that program administrators must address with documented insertion training before issuing the 6840 at scale. Without training, the actual attenuation gap can be substantial and OSHA compliance cannot be assumed from the NRR label alone. See our hearing conservation program guide for training requirements under 29 CFR 1910.95(k).

Cord Snag Risk Near Moving Equipment

The cord that makes the 6840 convenient in intermittent-noise environments becomes a potential hazard near rotating shafts, conveyor belts, gears, or other moving parts. OSHA's general industry machine-guarding standards (29 CFR 1910.212) and machine-specific standards require that no loose clothing, jewelry, or accessories be worn near these hazards — and a dangling earplug cord qualifies. Safety managers should complete a cord-hazard assessment for each work station before issuing corded earplugs. In high-rotation-machinery areas, the uncorded 6820 or a banded earplug may be safer.

Single-Use Cost Structure

The 6840 is a disposable plug. At $0.56 per pair, daily replacement for a crew of 50 is approximately $7,000 per year at one pair per shift. Reusable hearing protection options — pre-molded plugs or earmuffs — carry higher upfront costs but dramatically lower consumable costs on a two- to three-year horizon. For environments where ear canal hygiene is manageable and workers are willing to maintain reusable plugs, the total cost of ownership calculation can favor non-disposable alternatives. The 6840's value proposition is strongest when convenience, cord retention, and latex-free compliance are the priorities.

Frequency-Specific Attenuation Limits

Like all foam earplugs, the Mellows provides its highest attenuation at high frequencies and less at low frequencies. Impact and impulsive noise sources — punch presses, nail guns, percussive tools — produce significant low-frequency energy that foam plugs attenuate less effectively than earmuffs or combination protection. For impulse-noise environments, consider whether the 6840 alone is sufficient or whether dual protection (plug plus muff) is appropriate under your program's exposure data.

Competitor Comparison

The 6840 distinguishes itself from the 3M 1110 on foam softness and NRR (30 vs 29), and from the Howard Leight MAX-30 on latex/PVC-free materials. Both competitors use standard polyurethane compounds. For programs where worker comfort on extended shifts and material exclusions are priorities, the Moldex 6840 is the stronger specification. For a curated ranking across brands, see our best earplugs for work guide.

Compatible Accessories

The Moldex 6840 is a self-contained disposable — no accessories are required for standard use. However, the following items support a complete hearing conservation program:

• Moldex PlugStation Dispensers: Wall-mount or free-standing dispensers accept the 6846/6847 formats (same foam, dispenser packaging). Keeps supply at point of use and supports OSHA record-keeping for issued PPE.
• Hearing protection signage: Required by OSHA 29 CFR 1910.95(e) in areas where noise TWA exceeds 85 dBA. Available through your facility's PPE vendor.
• Audiometric testing services: OSHA mandates baseline and annual audiograms for workers in HCP programs. The 6840 supports your program; a testing service closes the regulatory loop.

For workers who need both hearing and eye protection in the same zone, see our full PPE collection for compatible safety glasses and face shields. For broader hearing protection options including earmuffs and banded plugs, browse our hearing protection collection.

OSHA and ANSI Standards Context

The Moldex 6840 is rated under ANSI S3.19-1974, which is the standard OSHA references in 29 CFR 1910.95 for verifying hearing protector attenuation adequacy. The NRR is the single metric OSHA specifies for program adequacy calculations.

To verify that NRR 30 is adequate for a given work area, apply OSHA's recommended 50% derating formula:

Effective Attenuation (dB) = (NRR − 7) ÷ 2
For the Moldex 6840: (30 − 7) ÷ 2 = 11.5 dB

Subtract 11.5 from the measured TWA to estimate the worker's corrected noise dose. If the result is at or below 90 dBA (PEL) and ideally at or below 85 dBA (action level), the 6840 is adequate. If the corrected dose exceeds 85 dBA, a higher-NRR plug, earmuff, or dual-protection approach is needed. Our NRR hearing protection guide walks through this calculation in detail with additional examples.

OSHA also requires that hearing protectors be provided at no cost to workers at or above the action level (85 dBA TWA), that workers be trained in correct insertion, and that the protector be replaced when damaged or hygiene is compromised. The 6840's disposable design inherently satisfies the last requirement. For a full program framework, see our hearing conservation program guide.

Total Cost of Ownership

At $56.07 per 100-pair bag, the 6840 costs approximately $0.56 per pair. For a 50-worker operation replacing plugs daily over 250 working days:

• Annual consumable cost (1 pair/day): 50 workers × $0.56 × 250 days = ~$7,000/year
• With cord-driven retention reducing replacement by 30%: approximately $4,900/year

If your crew averages more than one pair per shift due to plug loss with uncorded formats, the cord's retention benefit can offset the 6840's modest premium over the 6820. For programs running 100+ workers, evaluate the 6846/6847 PlugStation formats, which reduce handling waste and point-of-use labor. Explore reusable alternatives in our reusable vs. disposable earplugs guide if long-term cost reduction is the priority.

Final Verdict

The Moldex 6840 Mellows Corded Earplugs deliver exactly what their specification promises: NRR 30 attenuation from a latex-free, PVC-free, ultra-soft foam roll-down with the practical advantage of a retention cord. It is not the highest-attenuation earplug in the Moldex catalog, and it is not intended to be. For the broad middle of American industrial noise environments — 85 to 97 dBA TWA — it is a well-engineered, compliance-ready solution. The cord makes it operationally superior to uncorded formats in intermittent-exposure areas. The soft foam formula supports compliance on extended shifts. The latex/PVC-free materials eliminate a common PPE exclusion problem without requiring a separate inventory.

If those factors align with your program's needs, the 6840 earns a confident recommendation. If you need NRR 33, cord-free design, or reusable format, the Moldex family has those options. For all other moderate-noise programs, the 6840 belongs on the short list. Read our best hearing protection guide to see how it stacks up across the full market.

Frequently Asked Questions

What is the NRR of the Moldex 6840?

The Moldex 6840 has an NRR (Noise Reduction Rating) of 30 dB, tested and rated under ANSI S3.19-1974. This is the label rating. Applying OSHA's recommended 50% derating, the real-world attenuation is approximately 11.5 dB. See our NRR guide for how to apply this to your exposure measurements.

Is the Moldex 6840 latex-free?

Yes. The 6840 is manufactured from ultra-soft polyurethane foam that contains no latex and no PVC. It is suitable for workers with latex sensitivities and programs that restrict certain plasticizers in skin-contact PPE.

What is the difference between the Moldex 6820 and 6840?

The 6820 is the uncorded version (200 pairs per bag) and the 6840 is the corded version (100 pairs per bag). Both use identical latex-free, PVC-free, NRR 30 ultra-soft polyurethane foam. The cord on the 6840 allows workers to hang the plug around their neck during brief quiet periods rather than pocketing or losing it.

How do I correctly insert the Moldex 6840?

Roll the earplug between thumb and forefinger into a thin cylinder. With the opposite hand, reach over your head and pull your ear up and back to straighten the canal. Insert the rolled plug and hold it in place for 20–30 seconds while it expands to fill the canal. A proper fit creates a full seal with no gaps. Improper insertion is the most common cause of below-spec real-world attenuation in roll-down foam earplugs.

Is the Moldex 6840 OSHA compliant?

The 6840 meets the requirements of OSHA 29 CFR 1910.95 for hearing protector adequacy when its NRR 30 rating (derated per OSHA's 50% method to 11.5 dB effective attenuation) reduces worker exposure to at or below the permissible exposure limit of 90 dBA TWA. Full OSHA compliance also requires training, audiometric testing, and a written hearing conservation program — the earplug alone does not constitute compliance.

What noise environments is NRR 30 adequate for?

Using OSHA's 50% derating formula (11.5 dB effective attenuation), NRR 30 is adequate to the 90 dBA PEL for TWA exposures up to approximately 101.5 dBA, and adequate to the 85 dBA action level for environments up to approximately 96.5 dBA TWA. For exposures above these thresholds, a higher-NRR device or dual protection is required.

Can the Moldex 6840 be used for shift-long wear?

The Mellows foam's ultra-soft formulation is specifically designed to reduce canal pressure on extended wear. Workers who find standard roll-down foam uncomfortable after 2–3 hours often report better tolerance with the Mellows compound. That said, all foam earplugs should be inspected for hygiene and replaced per your program's replacement schedule.

Is the cord on the 6840 a safety hazard?

The cord can create a snag risk near rotating shafts, conveyor belts, or moving machinery. Before issuing corded earplugs at a workstation, safety managers should assess whether the cord creates a hazard under OSHA 29 CFR 1910.212 (machine guarding) and related standards. In high-rotation-machinery areas, the uncorded 6820 or a banded alternative may be more appropriate.

How many earplugs come in the Moldex 6840 bag?

The Moldex 6840 bag contains 100 pairs (200 individual earplugs connected by cords). Each pair consists of two plugs connected by a single cord.

Where can I buy the Moldex 6840?

The 6840 is available directly from WC Safety and through Amazon. Purchasing from WC Safety supports a veteran-owned PPE retailer and ensures you receive an authentic product with current lot numbers.

Does Moldex make a higher-NRR version of the Mellows?

No. The Mellows series is Moldex's NRR 30 foam line. For NRR 33 — Moldex's maximum-attenuation foam earplug — look at the Moldex 6800 series (SparkPlugs). For a full comparison of Moldex earplug lines, see our best Moldex earplugs guide.

What is the shelf life of the Moldex 6840?

Moldex does not publish a specific shelf life for the 6840. Generally, polyurethane foam earplugs should be stored in a cool, dry environment away from UV light and used within 3–5 years of manufacture. Plugs that have become hard, brittle, or no longer return to shape after compression should be discarded — they will not form a proper seal.

Can the Moldex 6840 be reused?

The 6840 is a disposable, single-use earplug. It can be reinserted within the same shift if removed briefly (the cord facilitates this), but it should not be washed and reused across multiple shifts. Foam degrades with handling, sweat, and contamination, reducing both attenuation and hygiene. For programs requiring reusability, see our reusable vs. disposable earplugs guide.

How does the Moldex 6840 compare to earmuffs?

Roll-down foam earplugs at NRR 30 typically outperform standard over-ear earmuffs (most fall in the NRR 22–28 range) on raw attenuation. However, earmuffs have advantages in ease of donning/doffing, suitability for workers with ear canal issues, and lower long-term consumable costs. For high-noise environments, dual protection (earplug plus earmuff) is the highest-attenuation approach. Browse our hearing protection collection for earmuff options.

Are there Moldex 6840 PlugStation formats?

Yes. The Mellows foam is also available in 6846 (250-pair PlugStation) and 6847 (500-pair PlugStation) formats. These are designed for Moldex wall-mount or free-standing dispensers used in high-traffic supply stations. The foam and cord are identical to the 6840; only the packaging changes.

Does WC Safety sell other Moldex earplugs?

Yes. WC Safety carries a range of Moldex hearing protection products. See our hearing protection collection or our guide on best earplugs for work for a curated selection across NRR ratings, formats, and use cases.

What is the best earplug for very loud environments above 100 dBA?

For sustained exposures above 100 dBA TWA, NRR 33 earplugs, high-attenuation earmuffs, or dual-protection combinations are recommended. See our best hearing protection guide and our hearing conservation program guide for selection criteria at high exposure levels.

What foam color are the Moldex 6840 earplugs?

The Moldex 6840 earplugs are peach/beige in color. The color does not affect attenuation or performance; it is a design characteristic of the Mellows foam formulation.

Reviewed by Steven Eaton
Steven Eaton is the founder of WC Safety and a veteran of the U.S. armed forces with hands-on experience in industrial PPE selection, OSHA compliance, and hearing conservation program administration. He reviews all hearing protection content published under the WC Safety editorial brand.

Methodology: Specifications drawn from the manufacturer's product page at wcsafety.com. Attenuation calculations performed per OSHA's 50% NRR derating method as specified in OSHA 29 CFR 1910.95 Appendix B. Competitor data drawn from publicly available manufacturer specifications. No laboratory testing was conducted by WC Safety for this review.