A noise level of 100 decibels would correspond to noise from a machine-shop.

The decibel (dB) scale is commonly used to measure the intensity or loudness of sounds. It is a logarithmic scale, which means that each increase of 10 dB represents a tenfold increase in sound intensity. In this scale, a noise level of 100 decibels is considered very loud and can be associated with noisy industrial environments, such as machine shops, construction sites, or heavy machinery operations.

To provide some context, here are the approximate sound levels of common everyday sounds:

- Just audible sound: Around 0-10 dB (e.g., a ticking watch)

- Ordinary conversation: Around 60-70 dB (e.g., speaking to someone in a quiet room)

- Sound from a noisy street: Around 70-80 dB (e.g., city traffic or a busy street)

Therefore, a noise level of 100 decibels is significantly higher than the sound levels associated with just audible sound, ordinary conversation, or sound from a noisy street. It is more comparable to the noise levels typically encountered in a machine-shop setting.