Odor measuring device
Odor Sensing Instruments
30+ years of odor sensor development. Over 2,000 units sold worldwide.
Kalmor’s odor sensors are designed by certified odor assessors for real-world field use —
from portable spot-checks to 24/7 continuous monitoring.
Fixed-point
Rental Available
CSV Export
30+ Years
Product Lineup
Two instruments, designed for different measurement needs.
POLFA
A lightweight (375g) handheld odor sensor for on-site odor checks.
Displays real-time values and graphs. Zero-point calibration for detecting
subtle differences. CSV export via microSD.
- Quality control — incoming/outgoing odor checks
- Effectiveness testing — before/after deodorization
- Environmental surveys — factory perimeter monitoring
LIMOS
A 24/7 automated odor monitoring system. Install outdoor sensors at property
boundaries to continuously track odor levels. Cloud-based data storage with
threshold alerts via email. View data anytime from PC or mobile.
- Unattended monitoring — 24-hour automated measurement
- Leak management — custom threshold alerts
- Daily management — CSV export for reporting
How to Choose the Right Sensor
Compare POLFA and LIMOS to find the best fit for your application.
| Feature | POLFA (Portable) | LIMOS (Fixed-point) |
|---|---|---|
| Measurement type | On-demand, handheld | Continuous, automated |
| Best for | Spot-checks, surveys, QC | 24/7 perimeter monitoring |
| Installation | None — carry to location | Fixed outdoor sensor units |
| Monitoring | Manual readings + peak hold | Real-time cloud dashboard |
| Alerts | — | Threshold-based email alerts |
| Data export | CSV via microSD | CSV from cloud / wireless |
| Weight | 375g | Fixed installation |
| Rental | 1-week rental | 1-week or 1-month rental |
- You need to measure at multiple locations
- Odor checks are part of daily QC routines
- You want to compare before/after deodorization
- Budget and portability are priorities
- You need continuous, unattended monitoring
- Odor complaints require 24/7 boundary surveillance
- You want automatic alerts when thresholds are exceeded
- Cloud-based data access is important
How Odor Sensors Work
Semiconductor-based gas detection — simple, reliable, and field-proven.
Semiconductor Sensing
A heated sensor element adsorbs oxygen, which traps electrons and restricts
electrical flow. When odor molecules (reducing gases) contact the sensor,
oxygen is displaced, freeing electrons and increasing conductivity.
This change in resistance is measured and converted to a numerical value.
PF Value — Kalmor’s Proprietary Scale
The voltage difference between the baseline state (sensor ON, clean air) and
the measurement state (odor present) is processed through Kalmor’s proprietary
algorithm to produce the PF value. This value correlates with overall odor
intensity — not a specific chemical. Custom odor index conversion formulas
are available upon request.
Use Cases & Industries
Deployed across diverse sectors for odor measurement, monitoring, and
compliance.
Food Manufacturing
Monitor exhaust odor levels, verify deodorizer effectiveness,
and manage odor complaints from neighboring areas.
Waste & Recycling
Track boundary odor concentrations at waste processing facilities.
Continuous LIMOS monitoring for regulatory compliance.
Chemical & Pharmaceutical
QC checks for raw materials, intermediates, and finished products.
Detect process leaks and ventilation issues.
Environmental Consulting
Field surveys for odor dispersion studies and impact assessments.
POLFA’s portability makes multi-point surveys efficient.
Building Management
Indoor air quality monitoring in commercial buildings,
tenant complaint investigation, and HVAC performance verification.
Research & Development
Material odor testing, packaging evaluation, and product
development for consumer goods, cosmetics, and automotive.
Rental Programs
Try before you buy — all sensors available for short-term rental.
1-Week Portable Rental
Receive a fully calibrated POLFA unit by courier. Lightweight and portable —
no installation required. Includes microSD card for data export.
Technical support available throughout the rental period.
Contact for pricing
1-Week or 1-Month Fixed-point Rental
Deploy LIMOS at your facility boundary to assess odor leakage levels.
Two plans available: with or without on-site installation support.
1-month plan recommended for comprehensive odor profile analysis.
1-week plan available for equipment evaluation.
Contact for pricing
Why Kalmor Sensors
Three decades of refinement by certified odor assessment professionals.
Designed by Odor Experts
Not all sensors are equal — even with identical sensing elements, output values
depend on proprietary algorithms. Kalmor’s sensors are developed by certified
odor assessors (national qualification) with 30+ years of field experience.
Every feature reflects real-world measurement needs.
2,000+ Units Sold
Over 90% of cumulative sales are portable sensors — testament to POLFA’s
usability. Featured in major TV programs and industry publications.
High repeat purchase and rental-to-purchase conversion rates validate
the product’s real-world value.
Try Before You Buy
Every product is available for rental or demo before purchase.
Want to verify if your target odor can be effectively measured?
Kalmor’s odor assessment team supports you from trial through deployment.
Most rental customers proceed to purchase.
FAQ
Can the sensor identify the source of an odor?
The sensor can help narrow down which room or area an odor is coming from
by comparing readings at multiple points. However, tracing odors through
complex pathways (ducts, wall cavities, etc.) requires specialist investigation.
Kalmor offers professional odor source investigation services for these cases.
Can it measure the Odor Index (臭気指数)?
POLFA outputs its proprietary PF value, not the Odor Index directly.
However, Kalmor offers a custom conversion formula service that maps
PF values to estimated Odor Index values for your specific odor type.
Contact us for details.
What is the difference between Odor Index and sensor value?
The Odor Index is a legally defined measure under Japan’s Offensive Odor Control Law,
determined by human olfactory panels. Sensor values measure the total concentration
of reducing gases at the sensor element. While they don’t directly correlate,
Kalmor’s conversion service can bridge the two for practical use.
Can LIMOS be used outdoors?
Yes. LIMOS is designed for outdoor deployment at property boundaries.
However, installation in extremely high-humidity areas or locations exposed
to salt spray is not recommended.
Can odor types be distinguished?
No. Kalmor sensors measure total gas concentration as a single composite value.
They do not distinguish between pleasant and unpleasant odors, nor identify
specific chemical compounds. For substance-specific analysis, consider Kalmor’s
odor component analysis service.
Can I use it to measure deodorizer effectiveness?
Yes — for deodorizers that reduce gas concentration (adsorption, decomposition, etc.),
before/after comparison with POLFA is effective. Note that masking-type deodorizers
(which add fragrance) may cause sensor values to increase rather than decrease,
as the sensor responds to the added fragrance compounds as well.
Find the right sensor for your needs.
Contact us for consultation, rental, or product details.