TM 10-6630-245-13&P
results become. Some tests may not work at all under extreme conditions. The WQAS-PM is not recommended for use
in subzero temperatures.
2.7.2. Heat: May affect the results of tests done with the WQAS-PM. In hot environments tests should be done in a
shaded and well ventilated area. Test results may become less accurate as temperatures rise, but may still serve as
valid approximations for many applications. Specific possible effects of higher temperatures include:
a.
Possible Effects
(1)
Temperatures above 77°'F (25°'C) may lower accuracy.
(2)
Reactions proceed faster, especially in tests using indicator testing.
(3)
Greater risk of losing oxygen dissolved in water after taking a sample.
(4)
High temperatures may shorten reagent shelf life in proportion to how high and for how long the exposure
is.
b.
Precautions
(1)
Perform tests in shaded and well ventilated area.
(2)
Perform steps (1) through (6) of dissolved oxygen test (para 2.6.8.8) as quickly as possible.
(3)
Replace reagents more frequently.
2.7.3. Cold: May affect the results of tests and may prevent some tests from working at all if very cold. Specific possible
effects of cold include:
a.
Possible Effects
(1)
Ice crystals will form at temperatures below 32°F (0°C).
(2)
Reactions will slow down.
(3)
Plastic components will become brittle; may crack.
(4)
Frost may form on Spectrophotometer.
b.
Precautions
(1)
Heat water samples so no ice is present.
(2)
Carefully check powder pillows and labware for cracks and damage. Do not use if damaged.
(3)
Try to keep Spectrophotometer sample cells and contents above freezing temperatures.
(4)
WQAS-PM not recommended for use in sub-zero temperatures.
CAUTION
Do not try to heat reagents. May cause splattering or dangerous reactions.
2.7.4. Sea and Salt Spray: May cause contamination or damage to equipment, but will not otherwise interfere with tests
if proper precautions are taken. Specific possible effects of sea and salt spray include:
a.
Possible Effects
(1)
Contamination of reagents and samples.
(2)
May cause damage to Spectrophotometer.
b.
Precautions
(1)
Take extra precaution to shield water samples and reagents from contamination from spray.
(2)
Avoid exposing the spectrophotometer to heavy moisture for extended periods of time.
(3)
Shield Spectrophotometer from salt or sea spray. Wipe surface clean after use with damp cloth. Check
for corrosion.
2.7.5. Dust and Sandstorms: May cause contamination or damage to equipment, but will not otherwise interfere with
tests if proper precautions are taken. Specific possible effects of dust and sandstorms include:
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