Question

In the context of gas testing using flame safety lamp, the correct statement is

• A. Each accumulation test has to be necessarily followed by percentage test
• B. Accumulation test is always done after percentage test
• C. Either percentage test or accumulation test can be done first
• D. Percentage test is done only in the event of accumulation test giving negative result

Hint:

Flame safety lamps are traditional tools for gas testing in mines, and following the correct testing sequence ensures accurate detection of flammable gases.

Answer 1

The Correct Option is D

When using a flame safety lamp for gas testing in mines, the standard procedure involves two types of tests: the accumulation test and the percentage test. The accumulation test is conducted first to detect the presence of flammable gases (like methane) by observing the flame's behavior in a concentrated gas pocket. If the accumulation test gives a negative result (i.e., no significant gas is detected), then a percentage test is performed to measure the actual concentration of gas in the air. This ensures that low levels of gas, which might not show in the accumulation test, are still quantified for safety. The percentage test is not mandatory after a positive accumulation test, as the presence of gas is already confirmed.
Thus, the correct answer is Percentage test is done only in the event of accumulation test giving negative result.