KOMYO RIKAGAKU North川-Type Dimethylacetamide (DMA) Gas Detection Tube 229S

Overview

The KOMYO RIKAGAKU North川-Type Dimethylacetamide (DMA) Gas Detection Tube 229S is a precision-engineered, single-use colorimetric indicator tube designed for rapid, on-site quantification of dimethylacetamide vapor in ambient or workplace air. Developed and manufactured in Japan by KOMYO RIKAGAKU—pioneer and world-leading producer of gas detection tubes since 1947—the 229S tube implements the validated North川 (Kitagawa) principle: controlled diffusion of sampled air through a glass tube pre-filled with a chemically selective reagent layer. Upon contact, DMA vapor reacts stoichiometrically with immobilized reagents (primarily acid-catalyzed hydrolysis products coupled with diazonium-based chromogenic agents), producing a sharp, linear color front progression along the calibrated scale. The endpoint position directly correlates to concentration via NIST-traceable calibration curves established under ISO/IEC 17025-accredited conditions. This method delivers field-deployable measurement without power, electronics, or calibration gases—making it ideal for industrial hygiene surveys, leak verification, confined space entry assessment, and emergency response where immediate qualitative-quantitative data is operationally critical.

Key Features

• Validated detection range of 5–70 ppm DMA (v/v), optimized for OEL compliance monitoring against ACGIH TLV® (TWA: 10 ppm) and EU-OEL (8-hour limit: 20 ppm)
• High specificity for dimethylacetamide; minimal cross-sensitivity to common solvents including acetone, DMF, NMP, and ethyl acetate (verified per JIS K 0804 Annex B interference testing)
• Standardized 100-mm tube geometry ensures consistent draw volume (100 mL per stroke with AP-20 pump) and reproducible front development kinetics
• Pre-calibrated linear scale with ±10% accuracy (k = 2) across full range, certified per manufacturer’s QC batch documentation
• Stable shelf life of 24 months when stored unopened at ≤30°C in original desiccated packaging; lot-specific expiration dates printed on tube label
• Compatible exclusively with KOMYO AP-20 dual-stroke hand pump (100 mL/stroke, 1.5–2.0 kPa suction pressure), ensuring repeatable sampling dynamics

Sample Compatibility & Compliance

The 229S tube is intended for grab sampling of atmospheric air in occupational environments, including chemical manufacturing, pharmaceutical synthesis, polymer processing, and coating application facilities. It performs reliably across temperature ranges of 5–40°C and relative humidity up to 85% RH (non-condensing). Each production lot undergoes rigorous validation per JIS K 0804:2020 “Method for Determination of Gaseous Substances in Workplace Atmospheres Using Indicator Tubes” and aligns with ISO 8573-6:2019 guidance for contaminant sampling in compressed air systems. While not a primary instrument for regulatory reporting, data generated supports preliminary exposure assessment compliant with OSHA 1910.1200 (Hazard Communication), EU REACH Annex XVII obligations, and internal GLP-aligned health surveillance programs. CE marking confirms conformity with EU Directive 2014/34/EU (ATEX) for use in non-hazardous zones.

Software & Data Management

As a passive, analog field tool, the 229S tube requires no firmware, drivers, or software integration. Quantitative results are manually recorded from the tube’s printed scale and entered into enterprise EHS platforms (e.g., Intelex, ETQ Reliance, or SAP EHS) via standard CSV templates. KOMYO provides downloadable PDF datasheets, lot-specific calibration certificates, and JIS-compliant test reports through its global distributor portal. For audit readiness, users are advised to retain used tubes (with annotated date/time/location/stroke count) for minimum 5 years—consistent with ISO 45001:2018 clause 7.5.3 record retention requirements.

Applications

• Routine time-weighted average (TWA) spot checks during DMA handling operations in API synthesis labs
• Verification of local exhaust ventilation (LEV) effectiveness at solvent dispensing stations
• Post-maintenance confirmation of residual DMA in reactor headspaces prior to personnel entry
• First-responder screening during transportation incidents involving DMA-labeled containers
• Educational demonstration of colorimetric gas analysis principles in university industrial hygiene curricula

FAQ

What pump is required for accurate use of the 229S tube?

The KOMYO AP-20 dual-stroke hand pump is mandatory; its fixed 100 mL displacement and regulated suction profile ensure metrological consistency per JIS K 0804.
Can the tube be reused after partial development?

No—each tube is single-use only. Reuse invalidates calibration and introduces carryover risk due to irreversible reagent consumption.
How does humidity affect measurement accuracy?

Results remain valid up to 85% RH; above this threshold, condensation may disrupt color front propagation—pre-drying the sample stream via silica gel trap is recommended.
Is there a digital reader available for the 229S tube?

KOMYO does not manufacture or endorse electronic readers for North川 tubes; visual interpretation by trained personnel remains the certified method per JIS standards.
Does the tube meet FDA or EPA regulatory requirements for environmental reporting?

It is not validated for EPA Method TO-17 or FDA environmental monitoring protocols; it serves as a screening tool—not a definitive compliance instrument—for occupational settings.