Altair 5 Manuel D'utilisation page 10

• Detect only specified toxic gases for which a sensor is installed.
(for available sensors,see Section 5.3)
• Perform a blocked flow test (see section 4.2) before each day's
use if equipped with an integral pump.
• MSA recommends to check the instrument's functionality
(see section 3.6) and carry out a routine inspection each day
before use.
• Perform calibration check (see section 3.7) before each day's use
to verify proper instrument operation. Adjust calibration if the
readings are not within the specified limits.
• Check calibration more frequently if unit is subjected to physical
shock or high levels of contaminants. Also, check calibration more
frequently if the tested atmosphere contains the following
materials, which may desensitize the combustible gas sensor and
reduce its readings:
• Organic silicones
• Silicates
• Lead-containing compounds
• Hydrogen sulfide exposures over 200 ppm or exposures over
50 ppm for one minute.
The minimum concentration of a combustible gas in air that can ignite is
defined as the Lower Explosive Limit (LEL). A combustible gas reading
of "100" or "5.00" indicates the atmosphere is above 100 % LEL or 5.00
%vol CH4, and an explosion hazard exists. Move away from hazardous
area immediately.
Do not use the ALTAIR 5 or ALTAIR 5 IR Multigas Detectors to test for
combustible or toxic gases in the following atmospheres as this may
result in erroneous readings:
• Oxygen-deficient or oxygen-rich atmospheres
• Reducing atmospheres
• Furnace stacks
• Inert environments (only IR sensors acceptable for use)
• Atmospheres containing combustible airborne mists/dusts.
Do not use the ALTAIR 5 or ALTAIR 5 IR Multigas Detectors to test for
combustible gases in atmospheres containing vapors from liquids with a
high flash point (above 38 °C, 100°F) as this may result in erroneously
low readings.
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