while dB is a more objective measure of pressure level.
Quibble: dB is not an objective measure, nor does it purport to be. It uses an objective yardstick (pressure) but it is scaled for hearing according to an approximation of subjective experiences (hearing) of pressure.
I’d also strongly suggest that not only “can” the frequency response measured off the TV be false, it will be false. It’s not just that TV sound has been highly processed, there’s just no way that the audio equipment a news crew uses picks up anything like the true sound of an environment, especially not the sort of full-spectrum noise emitted by an industrial compound. Of most interest here is that the signal picked up by those mics is liable to drop off somewhere below the range of human speech, whereas industrial equipment like that is liable to have big peaks beneath those frequencies and further, descending well past 20Hz (the bottom end of human hearing).
Persistent low frequency and sub-sonic noise is associated with severe mental distress and physical ailments.
In fact this is why it’s important to recognise the subjectivity of the decibels measure: (not only because) the body/brain responds differentially to frequencies across the spectrum, and at different volumes. It also responds according to all sorts of other variables, and these can’t really be untied from the question of noise level. Persistence, locatibility, perceived subjective control of one’s own aural environment - all of these are fundamentally tied to both the “physical” and “psychological” effects of hearing (insofar as these can be untied).
Some of the symptoms described in the article (nausea, vertigo, fainting, panic attacks) can be the result of all of these variables, given a sufficiently persistent uncontrollable sound source. You just can’t untie them and peg them all to objective noise level.
Others (such as hearing loss and fluid leaking out your ears) are associated with prolonged exposure to sub-sonic noise, and again this can be as much an issue of time and persistence as “objective” sound level.
If we want to know “how bad” a noisy environment is for people, we simply don’t have a choice but to look at its effects first. You just have to look at the subjective effects people experience first, or you’re not looking at sound in the first place. You’re grasping at some independent objective measure which won’t ever actually tell you what you want to know, except in the most limited circumstances.
Answer on a postcard