Carbon Monoxide Alarm User Manual

Page 42
Appendix D Suggested Calibration Gases
Use of a calibration standard with a concentration close to the alarm set point of the gas to be measured
affords the most accurate calibration of the sensors used in the
PhD
2
design. Because combustible gas
sensors have different responses to different combustible gases (see Appendix B), Biosystems offers three
choices.
Carbon monoxide, sulfur dioxide, chlorine, and hydrogen sulfide are all currently available from
Biosystems in small (103 or 58 liter), disposable, standard calibration gas cylinders. Stable calibration
mixtures are not available in disposable cylinders for several of the toxic sensors which may be used in the
PhD
2
detector.
For these gases it may be necessary to use other types of equipment, such as larger, high pressure
cylinders, permeation tubes and ovens, or gas generators to deliver the appropriate type of toxic gas to the
sensor. Please contact the factory for calibration procedures for specific toxic gases.
Please note: Biosystems EZ Cal

multi-component calibration gas mixtures are available for use
with many common PhD
2
detector configurations. The calibration gas supplied in Confined Space
Kits is normally an all-in-one mixture when one is available. If an all-in-one mixture is not desired,
please order the PhD
2
and calibration materials separately.
Gas Part Number Concentration Comments
EZ Cal multi-
component gas (CO,
methane, in air)
9041 CO 50 PPM, methane
50% LEL, in air
EZ Cal multi-
component gas (CO,
propane, in air)
9042 CO 50 PPM, propane
50% LEL, in air
EZ Cal multi-
component gas (CO,
H
2
S, methane, in air
9043 CO 50 PPM, H
2
S 25
PPM, methane 50%
LEL, in air
EZ Cal multi-
component gas (CO,
H
2
S, propane, in air)
9044 CO 50 PPM, H
2
S 25
PPM, propane 50%
LEL, in air
Methane (CH
4
) 9031 2.5% (= 50%LEL) in air Use when monitoring for presence
of methane or natural gas only.
Propane (C
3
H
8
) 9032 1.1% (= 50%LEL) in air Use for general purpose
combustible gas monitoring.
n - Hexane (C
6
H
14
) 9038 0.3% (= 25%LEL) in air
Carbon monoxide
(CO)
9033 50 PPM in air
Hydrogen sulfide
(H
2
S)
9034 25 PPM in nitrogen
Sulfur dioxide (SO
2
) 9037 10 PPM in nitrogen
Zero air 9039 20.9 % oxygen in
nitrogen
Use for fresh air calibration in
contaminated areas.
Ammonia (NH
3
) 9051 50 PPM in nitrogen
Chlorine (Cl
2
) 9052 5 PPM in nitrogen
Hydrogen cyanide
(HCN)
9054 10 PPM in nitrogen
Nitric oxide (NO) 9055 30 PPM in nitrogen
Nitrogen dioxide
(NO
2
)
9056 5 PPM in nitrogen