Which of the following noise levels is considered potentially harmful to human health if experienced over extended periods?
90 dB
The correct answer is 90 dB.
Sound intensity is measured in decibels (dB). Prolonged exposure to high decibel levels can cause significant hearing damage and other health problems. While lower decibel levels are generally considered safe, 90 dB and above are considered potentially harmful. Exposure to 90 dB for extended periods can lead to noise-induced hearing loss (NIHL).
Let's look at the options:
Therefore, only 90 dB represents a noise level that poses a significant risk to human health with extended exposure.
According to BIS SP 46-2003, which of the following applications is correctly represented by a chain-thin line in engineering drawings?
According to the ISO-A size series, what is the designation of a trimmed sheet with dimensions 297 mm × 420 mm?
A cube with a mass of 5.74 g occupies a volume of 1.2 cm³. The density (in g/cm³) expressed with the correct number of significant figures is ______.
Gaskets, seals and spacers are made using:
In a velocity-time graph, the negative slope represents ______.
For what purpose are pins and clips used in engineering drawings?
Which of the following statements is/are true about Functional Dimensions (F) in engineering drawing?
Statement 1: Functional Dimensions are essential to the function of the component or space.
Statement 2: Functional Dimensions are typically shown without limits.
Statement 3: Functional Dimensions are only shown for reference purposes.
Which of the following is true?
Which of the following statements is/are true?
Statement 1: Heat conductors allow heat to pass through them easily.
Statement 2: All plastics are good conductors of heat.
What does the symbol given below denote in a circuit diagram?

Magnetic Meridian is a
According to BIS SP 46-2003, which of the following applications is correctly represented by a chain-thin line in engineering drawings?
The force which makes a vehicle to stop when brake is applied is called __________.
According to the ISO-A size series, what is the designation of a trimmed sheet with dimensions 297 mm × 420 mm?