Tube - Water Vapour 5/a-P (10) | Draeger

The Dräger Tube “Water Vapour 5/a-P” (Order No. 6728531) is a glass detector tube designed for spot measurement of water vapour (H₂O) contamination in compressed gases or breathing air.
It is offered in a box of 10 tubes, making it suitable for repeated field or lab measurements.

Key Features & Benefits

• Fast, on-site measurement: The tube allows quick detection of water vapour without requiring full laboratory equipment. The reagent inside changes colour when H₂O is present, and the length of colour change correlates to the concentration.

• Wide measurement range: Depending on sampling volume, the measuring range covers from as low as 2 mg/m³ up to about 450 mg/m³ of H₂O. For a standard 50 L sample the range is approx. 5 – 200 mg/m³.

• Simple usage with compatible pump systems: The tube is intended for use with Dräger’s sampling systems (e.g., Aerotest® or Accuro® pump) for drawing a calibrated air sample through the glass tube.

• Compact and consumable format: Each tube is individually sealed and used once; the box of 10 allows multiple uses in industrial hygiene, compressed air monitoring, and confined-space checks.

Technical Specifications

• Measuring Range (typical):

  • For 50 L sample: approx. 5 – 200 mg H₂O/m³.

  • For 100 L sample: as low as ~2 mg/m³ up to ~80 mg/m³.

  • For 25 L sample: higher upper values (e.g., ~450 mg/m³) via scale extension.

• Test Volume / Flow Rate: The typical flow rate is 2 L/min for a 50 L sample (i.e., approx. 25 minutes measurement time).

• Colour change indicator: Yellow → Reddish-brown when water vapour is present.

• Operating ambient conditions: The recommended temperature is 0 °C to 40 °C for accurate measurement; only use with depressurized compressed air systems.

• Accuracy / Standard deviation: Approx. ±15-20% for the 50 L volume; ±20-25% for 100 L sample volumes.

• Cross-sensitivity: High concentrations of alcohols or unsaturated hydrocarbons may cause faint or diffused discoloration of the indicating layer (i.e., may interfere).

• Packaging: Each box contains 10 tubes (i.e., 10 tests).

• Shelf life: Most short-term detector tubes (including this type) have a shelf life of approximately 2 years if stored under appropriate conditions.

Typical Applications

• Monitoring humidity / water vapour contamination in compressed breathing air systems (e.g., for SCBA or industrial breathing-air supply).

• Checking the quality of compressed gases and ensuring they meet standards for moisture content.

• Field testing in confined spaces, tanks, sewers where moisture/water vapour levels may affect safety or equipment.

• Industrial hygiene audits: measuring peaks of water vapour in air to assess exposure or equipment integrity.

Usage & Operational Notes

1. Insert the tube into the compatible sampling pump system (e.g., Dräger Accuro).

2. Draw the calibrated volume (e.g., 50 L at 2 L/min) through the tube.

3. After sampling, observe the colour change front (yellow to reddish-brown) and read the corresponding concentration value from the printed scale on the tube.

4. If using non-standard sample volume (e.g., 25 L or 100 L), refer to extension tables to calculate the equivalent concentration.

5. Ensure ambient temperature is within 0-40 °C, and the compressed air supply is depressurized if required.

6. Be aware of potential interference: alcohols/unsaturated hydrocarbons in the sample may cause less sharp colour change.

7. After use, dispose of the tube according to your local hazardous-waste regulations (since chemical reagents inside may be used).

8. Store the tubes in their sealed packaging, away from direct sunlight, moisture, and extreme temperatures to preserve accuracy and shelf life.