KOKEN LTD.
Koken 7191 Series Dust Mask
Manufacturer: KOKEN LTD.
Model: 7191 Series
Important Points When Wearing a Respirator
Dust masks utilize high-efficiency filters to effectively prevent the inhalation of hazardous particles. To protect yourself from inhaling dust while wearing a mask, both the performance of the filter and the “tight seal” (fit) between the mask and your face are critical.
1. Filter Technology with High Particle Collection Efficiency
Mighty (Uni) Micron Filter
Using unique technology, wool fibers are electrostatically charged, allowing electrostatic force to draw particles to the fiber surface. This is the primary mechanism for capturing particles. A high-density fiber structure is unnecessary, successfully integrating the two contrasting features: “high collection efficiency” and “low inhalation resistance.” It consistently maintains the highest standard of performance and quality, making it an excellent long-term filter solution.
 |  |
Applied products are on P.4 ~ 6, P.11
Alpha Ring Filter
Increasing the fiber density of the filter enhances collection efficiency. To meet airflow resistance standards, paper filters traditionally require an expanded surface area.
For the first time in Japan, ultra-fine fibers were formed into pristine circular shapes in a single process, creating the Alpha Ring filter. Today, this filter continues to succeed in expanding the surface area while maintaining a compact shape, significantly reducing airflow resistance.
 |  |
Applied products are from page P.8 to P.11
Dust Respirator Standards
In addition to JIS standards, dust respirators are tested according to assay standards based on national regulations. These standards are comprehensive, ensuring that products meeting strict safety requirements are manufactured.
| Dust Respirator Standards | In addition to JIS standards, dust respirators are tested according to assay standards based on national regulations. These standards are comprehensive, ensuring that products meeting strict safety requirements are manufactured. |
|---|
Note: The table below is excerpted from the “Dust Respirator Standards”.
| Replaceable Dust Respirator | Isolation Type Dust Respirator |
|---|---|
| Direct-Connection Type Dust Respirator | |
| Disposable Dust Respirator | |
| Test Particles | Type | NaCl (Sodium Chloride) | DOP (Dioctyl Phthalate) | ||
|---|---|---|---|---|---|
| Particle Size | 0.06 μm to 0.1 μm | 0.15 μm to 0.25 μm | |||
| Concentration | 50mg/m³ or less | 100mg/m³ or less | |||
| Test Flow Rate | 85 ℓ /min | 85 ℓ /min | |||
| Particle Collection Efficiency (Continuous measurement; must meet values in the right column) | For NaCl particles Load up to 100mg | For DOP particles Load up to 200mg | |||
| Replaceable Type | RS1 | 80.0% or higher | RL1 | 80.0% or higher | |
| RS2 | 95.0% or higher | RL2 | 95.0% or higher | ||
| RS3 | 99.9% or higher | RL3 | 99.9% or higher | ||
| Disposable Type | DS1 | 80.0% or higher | DL1 | 80.0% or higher | |
| DS2 | 95.0% or higher | DL2 | 95.0% or higher | ||
| DS3 | 99.9% or higher | DL3 | 99.9% or higher | ||
| Inhalation Resistance (Test flow rate 40 ℓ /min) | Replaceable Type | Disposable Type | |||
| RS1 RL1 | 70Pa or less | DS1 DL1 | 60Pa or less (45Pa or less) | ||
| RS2 RL2 | 80Pa or less | DS2 DL2 | 70Pa or less (50Pa or less) | ||
| RS3 RL3 | 160Pa or less | DS3 DL3 | 150Pa or less (100Pa or less) | ||
| Exhalation Resistance (Test flow rate 40 ℓ /min) | Replaceable Type | Disposable Type | |||
| RS1 RL1 | 70Pa or less | DS1 DL1 | 60Pa or less (45Pa or less) | ||
| RS2 RL2 | 70Pa or less | DS2 DL2 | 70Pa or less (50Pa or less) | ||
| RS3 RL3 | 80Pa or less | DS3 DL3 | 80Pa or less (100Pa or less) | ||
Values in ( ) are for products without an exhalation valve.
| Exhalation Valve Airtightness | Exhalation valve operation leak test | – Internal pressure must drop immediately during suction. – Time for internal pressure to return to normal must be 15 seconds or more. |
|---|---|---|
| Carbon Dioxide (CO2) Concentration Increase | Measured using a test headform and artificial lung. The difference in CO2 concentration in inhaled air with and without the mask must be 1.0% or less. | |
| Dead Space | Value calculated from the CO2 Concentration Increase Test. | |
| Inhalation Resistance Increase | Test Particles | NaCl (Sodium Chloride) |
|---|---|---|
| Test Flow Rate | After dust accumulation at 85 ℓ/min, measurement is taken at 40 ℓ/min. | |
| Dust Accumulation Amount | 100mg |
Test Aerosol and Collection Efficiency Disposable Type | S | L | Classification (Particle Collection Efficiency) | |
|---|---|---|---|---|
| Test aerosol is solid Sodium Chloride (NaCl) | Test aerosol is liquid Dioctyl Phthalate (DOP) | |||
| R | Replaceable Dust Respirator | RS1 | RL1 | Class 1 (80.0% or more) |
| RS2 | RL2 | Class 2 (95.0% or more) | ||
| RS3 | RL3 | Class 3 (99.9% or more) | ||
| D | Disposable Dust Respirator | DS1 | DL1 | Class 1 (80.0% or more) |
| DS2 | DL2 | Class 2 (95.0% or more) | ||
| DS3 | DL3 | Class 3 (99.9% or more) | ||
High-Performance Filter + Facepiece Designed for Easy Fit
2. Facepiece Fit Technology
Even if a dust respirator has a high collection efficiency filter, it is meaningless if dust leaks through the face-to-mask seal during use. This is primarily caused by a “gap at the face contact area when worn.” We consider the fit of the mask to be as important as the filter performance. Therefore, our company has developed technologies to enhance the airtightness of the facepiece seal.
Silicone Facepiece
Silicone is a hypoallergenic material that is gentle on the skin. Its surface is flexible and effortlessly adapts to body movements, ensuring a comfortable fit and stability during use.
HAWC Lip Structure
The lip design ensures a high degree of adhesion, maximizing the “suction cup” effect when wearing the mask to ensure an airtight facial seal.
Free Position Under Chin
The unique curve of the face contact area prevents dust from leaking in. By aligning the nose portion first, it accommodates various facial dimensions, providing a secure fit for a wide range of face sizes (see image below).
Fit Status of the Free Position Under Chin Mask
(Simulated image with the mask cut away to clearly show where it contacts the chin).
| For individuals with large faces: The outer section of the mask rests naturally against the chin to provide a proper fit. |  | For individuals with small faces: The inner section of the mask naturally positions itself against the chin to secure the fit. |  |
| FF Lip | Wearing Stability | Built-in Fit Checker | |||
|---|---|---|---|---|---|
 | Designed to naturally conform to various facial sizes and shapes, providing a seamless fit. |  | Uses a 3D-shaped polyband harness that conforms to the shape of the head, enhancing fit and sealing performance. |  | A built-in fit checker allows you to test the mask’s seal at any time (available for the 1005, 1010A, 1015, and 1180 series). |
Head Harness Types
Please replace the head straps periodically.
Sakai Model 7191DK-03
Equipped with a speaking diaphragm for clear communication and instructions.
RL3 Classification
Type Certification: TM645
Assigned Protection Factor: 10
Can be used as a gas mask (Model 7191DKG · Class L3)
(Absorbent canisters sold separately)
Type Certification: TN179
- Under Chin Cushion
- Silicone Facepiece
- Speaking Diaphragm
| Particle Collection Efficiency | 99.9% or more (Average 99.99%) |
|---|---|
| Inhalation Resistance | 85Pa or less (Average 69Pa) |
| Exhalation Resistance | 35Pa or less (Average 18Pa) |
| Resistance Increase | ― (Average 84Pa) |
| Weight | 198g or less (Average 183g) |
| Head Harness | XDB Type |
Replacement Parts:
- Inhalation Valve (Circular)
- Exhalation Valve T-1K
- Egg-shaped Moisture Sponge
Sakai Model 7191DKU-02
Suitable for nanomaterial handling.
Particle collection efficiency: 99.999% (average value).
Equipped with a speaking diaphragm allowing conversation while wearing the mask.
RL3 Classification
Type Certification: TM674
Assigned Protection Factor: 10
- Under Chin Cushion
- Silicone Facepiece
- Speaking Diaphragm
| Particle Collection Efficiency | 99.99% or more (Average 99.999%) |
|---|---|
| Inhalation Resistance | 105Pa or less (Average 69Pa) |
| Exhalation Resistance | 35Pa or less (Average 20Pa) |
| Resistance Increase | ― (Average 85Pa) |
| Weight | 203g or less (Average 183g) |
| Head Harness | XDB Type |
Replacement Parts:
- Inhalation Valve (Circular)
- Exhalation Valve T-1K
- Egg-shaped Moisture Sponge
Notes on Filter Replacement
As dust accumulates in the filter, airflow resistance increases, making breathing more difficult. Furthermore, if the mask is not perfectly sealed against the face, dust may enter through gaps created by the increased breathing effort.
- Always perform a seal check before use and ensure the mask is firmly secured to the face.
- Replace the filter before breathing becomes difficult to prevent excessive airflow resistance.
*If you have any questions regarding part replacement, please contact our office or local agent.
Replacement Filters · Optional Accessories
| RD-6 (For: 1721H, 1521H, 7121R, 7191DK) | RD-6U (For: 7191DKU, 1521U) | RD-8 (For: 1180H) | LAS-52 (For: 1781DW) | LAS-52C (For: 1781DWC) | (Optional) Fit Tester – Type V Applied models: 1721H, 1521H, 1521U, 7121R, 7191DK, 7191DKU | (Optional) Fit Tester – Type F Applied models: 1781DW, 1781DWC |
 |  |  |  |  |  |  |
| 2 pcs/set — Threaded | 2 pcs/set — Threaded | Threaded | 2 pcs/set — Threaded | 2 pcs/set — Threaded |
- Fit Checker: Just operate the lever to perform a user seal check (fit test).
- Under-Chin: Unique curve enhances the airtight seal between face and mask.
- Silicone: Soft, skin-friendly material; silicone facepiece ensures comfortable long-term wear.
- HAWC Lip: High airtightness achieved through a “suction effect”; applied to full-face models.
- Size S Available: Small face size options are available for these models.
- Low Breathing Resistance: Alpha Ring filter technology allows for prolonged usage with minimal fatigue.
- Speaking Diaphragm: Integrated device enables clear verbal communication while wearing the mask.
- Activated Carbon: Effectively neutralizes low-concentration ozone; utilizes carbon-impregnated filters.
- Surface Hardening: The visor lens is treated to resist scratches.
- Special Surface Hardening: Advanced coating provides superior scratch protection over standard treatments.
Note: Consumable components and filters should be replaced promptly according to the maintenance schedule.
REQUEST QUOTATION
PAYMENT
LINK
