Tube - Chlorobenzene 5/a | Draeger

The Dräger Tube for Chlorobenzene (5/a) is a glass-chemical sampling tube designed for quick field detection of chlorobenzene vapour in air. It is part of the Dräger “Tube” system of short-term gas measurement devices.

Key Specifications & Features

• Measuring Range: 5 to 200 ppm of chlorobenzene.

• Number of strokes: Designed for about 10 strokes (i.e., 10 pump actions) to draw a calibrated air sample.

• Approximate time for measurement: Around 3 minutes from start of sampling to reading.

• Standard deviation (precision): ±10-15 % typical for this tube.

• Operating ambient conditions: Temperature ~10 °C to 40 °C; absolute humidity between ~3 to 15 mg H₂O/L.

• Reaction principle:

  • The target gas (chlorobenzene, C₆H₅Cl) reacts with Cr(VI) in the reagent to generate HCl.

  • The HCl then reacts with bromophenol blue indicator dye, causing a visible color change (from blue to yellowish-grey) that indicates presence and approximate concentration.

• Cross-sensitivity: Other chlorinated hydrocarbons may show a response (with different sensitivities). Methylene chloride does not affect the indication. Chlorine and hydrogen chloride in TLV‐range are absorbed in a pre-layer and do not significantly interfere.

• Shelf life: Some listings indicate a 2-year shelf life when stored properly.

• Packaging: Typically sold in packs (for example, 10 tubes or “5 tests per box” depending on vendor).

Usage & Application

• The tube is used together with a compatible pump (for example the Dräger Accuro® bellows pump) which draws a known volume of air (typically 100 ml) through the tube.

• If chlorobenzene is present in the sampled air, the reagent inside the tube will change colour along its length; the length of the colour‐change corresponds to the concentration in ppm.

• Typical field applications include: measurement of exposure peaks in inhalation zones, leak detection in tanks/shafts/confined spaces, or area monitoring in chemical works where chlorobenzene may be used.

• Because the measurement is quick (≈ 3 minutes) and portable, it enables rapid on‐site checking without needing laboratory analysis.

Advantages

• Portable & fast: Allows field measurements rather than waiting for lab results.

• Selective: Specifically calibrated for chlorobenzene in the given range.

• Ease of use: Minimal training required; just insert tube, attach pump, draw air, and read the indication.

• Well‐known system: The Dräger tube system is widely used and trusted for short‐term gas/vapor detection.

Considerations & Limitations

• Because it is a spot measurement tool, it gives a snapshot at the time of sampling; for continuous monitoring you’d require a different system.

• It has a defined measuring range (5-200 ppm) — concentrations outside this range may not give accurate readings.

• There is potential cross‐sensitivity: other chlorinated hydrocarbons might trigger a response (but with different sensitivity). One must interpret with chemical context.

• The indicated accuracy (±10-15 %) means it's best used for screening rather than ultra‐precise quantification.

• Storage conditions matter: exposure to high humidity, temperature extremes or prolonged storage beyond shelf‐life may degrade the reagent and affect accuracy.