Tube-Hydrogen Sulfide 2/a (10) | Draeger

This product is a set of 10 short-term detection tubes designed for measuring the concentration of hydrogen sulphide (H₂S) gas in air. It uses the well-established Dräger Tube system: draw a defined volume of air through the reagent-filled glass tube, and the reagent reacts with H₂S causing a colour change; the extent of the colour change correlates with concentration.

Key Specifications

• Target gas: Hydrogen sulphide (H₂S) – chemical detection in ambient air.

• Measuring range:

  • Primary range: 20 to 200 ppm

  • Secondary/low range: 2 to 20 ppm

• Measurement time:

  • For full scale (20-200 ppm): ~ 20 seconds

  • For low range (2-20 ppm): ~ 3.5 minutes

• Number of strokes:

  • For high range: 1 stroke

  • For low range: 10 strokes (as per specification sheet)

• Colour change indicator: white → pale brown, indicating reaction progression.

• Reaction principle: H₂S + Hg²⁺ → HgS + 2H⁺ (i.e., hydrogen sulphide reacts with mercury ions to form mercury sulphide)

• Ambient operating conditions: Temperature 0-40 °C, absolute humidity 3 to 30 mg H₂O/L.

• Cross-sensitivity / interferences: Not influenced by 200 ppm SO₂, 100 ppm HCl, 100 ppm ethyl mercaptan.

• Packaging: Box of 10 tubes (10 tests per box)

Features & Benefits

• Fast spot-measurement capability: for higher concentrations (~20–200 ppm), the measurement time is very short (~20 s), enabling rapid detection of H₂S peaks.

• Dual range flexibility: The tube can cover both a low-range (2–20 ppm) and a higher range (20–200 ppm) — suitable for both lower exposure monitoring and higher hazard situations.

• Robust and field-ready: The Dräger Tube system is widely used in industrial hygiene, environmental monitoring and onsite gas detection for quick checks and verification.

• Clear visual indicator: The colour change from white to pale brown gives immediate visual confirmation of the presence of H₂S.

• Low interference: Good selectivity with minimal cross-sensitivity to certain interfering gases (SO₂, HCl, mercaptans) in listed amounts.

• Compact, self-contained: The tubes require only the appropriate pump (e.g., Dräger Accuro or similar) to draw the sample; no complex instrumentation required.

Typical Applications

• Monitoring H₂S in industrial workplaces: oil & gas, petrochemicals, wastewater treatment, sewers.

• Emergency response or leak detection situations where quick spot checks are needed.

• Complementary verification for continuous monitors: e.g., confirming peaks, spotting non-continuous sources.

• Environmental or safety audits where H₂S is a potential hazard.

Usage & Handling Tips

• Ensure you have a compatible pump (e.g., Dräger Accuro) and correctly calibrate/verify it before use.

• Confirm that the ambient temperature and humidity are within specified range (0–40 °C, 3–30 mg H₂O/L) for accurate results.

• For low-range measurement (2–20 ppm) use the 10 strokes as specified — drawing the correct sample volume is key.

• Use proper break-off tool (tip of the glass tube) to open according to instructions to avoid glass splinters.

• After sampling, read the length of the colour change immediately and interpret per the scales printed on the tube.

• Store the tubes in original packaging, protected from strong light, high humidity and extremes of temperature to maintain shelf-life and reagent integrity.

• Dispose of used tubes as glass chemical waste following local regulations.

Limitations & Considerations

• These are spot-measurement tubes, providing an instantaneous snapshot, not a time-weighted average over long durations.

• The measurement is semi-quantitative: the visual scale reading may have an uncertainty of ±5–10% (as per spec) under ideal conditions.

• For very low levels (below 2 ppm) or very long-term monitoring, a different (more sensitive or continuous) monitoring instrument may be required.

• Proper handling is required: break glass tube carefully, avoid contamination of reagents, ensure pump stroke volume is correct.

• Ensure the selected range fits the expected concentration – if the expected concentration is much higher than 200 ppm, you may need a tube with higher range or a continuous monitor.

• The reagent is specific to H₂S under given conditions; if unknown interfering gases exist outside the listed, check whether additional cross-sensitivities apply (consult full manufacturer data).

• Storage and shelf-life: As with most gas detection tubes, reagent efficacy decreases with age, improper storage or exposure to adverse conditions — always check expiry date and storage conditions.