Hydrogen cyanide HCN NO.12L


Performance

Measuring Range

0.36 to1.25 ppm

1.25 to2.5 ppm

2.5 to 60 ppm

60 to120 ppm

Number of Pump Strokes

5

2

1

1/2

Correction Factor

1/7

1/2

1

2

Sampling Time

2 minutes per pump stroke

Detecting Limit

0.1 ppm (n=5)

Color Change

Yellow Red

Reaction Principle

Hydrogen cyanide reacts with mercuric Chloride to form
the hydrogen chloride then discolors the indicator to red.
2HCN + HgCl2→ Hg(CN)2+ 2HCl HCl + Base Chloride product
Coefficient of Variation

10% (for 2.5 to 20 ppm), 5% (for 20 to 60 ppm)
Shelf Life 2 Years
Corrections for
temperature & humidity		 Humidity correction is necessary
Store the tubes at cool and dark place.


Possible coexisting substances and their interferences (NOTE)

Substance

Concentration

Interference

Change color by itself

Sulfur dioxide

20 ppm

Plus error

Red discoloration

Hydrogen sulfide

5 ppm

Plus error

Red discoloration


Other substance measurable with this detector tube

Substance

Correction Factor

Pump Strokes

Measuring Range

Acetone cyanohydrine

1.15

1

2.88 to 69 ppm

Boron trichloride

by scale

2

0.5 to 20 ppm


Calibration gas generation Permeation tube method


TLV-TWA TLV-STEL Explosive range
- C 4.7 ppm 5.6 to 40%

Copyright(c) 2001 GASTEC CORPORATION. All rights reserved.