[Marxism] Re: Noise and workers' hearts

Marla Vijaya kumar marlavk at yahoo.com
Sat Nov 26 09:45:20 MST 2005

Les Schaffer wrote: “are these active or passive suppresion schemes? 
Much too big for active is my guess. what is the extra cost to capital 
to add in a truly effective (passive) noise suppresion?
Is this an area where a move to automated measurement systems is 
resisted because of costs? 100 calibrated microphones (and/or 
accelerometers)  plus several PCs w/ data acquisition cards could save 
a lot of ears.
my reason for asking:  over the last 10 years there is a big move to 
doing machinery health monitoring in the US and some other countries. 
i've often thought capital is willing to spend more on machinery health 
care than for the health care of its human laborers. are conditions in 
India similar or different?
my reason for asking:  over the last 10 years there is a big move to 
doing machinery health monitoring i
I meant to say **automated** machinery health monitoring”
Reply: Your guess is correct, Les. A 125 MW steam turbine 
and generator train (machines coupled to one another) will
weigh a good 300T or more and can be about 10-12 M long. 
It is unthinkable at this stage of technology to suppress 
noise by active means. We only use frame enclosures with 
padding materials for passive suppression of noise. A noise
 suppression enclosure to bring down noise from say 105 dBA
 to 90 dBA can cost as little as 0.15 million USD for a 
125 MW turbine generator combination.
Automatic monitoring of noise level in industries and 
especially in power plants has not yet picked up, but 
I am sure it costs much more than manual monitoring. 
Noise suppression is not a very serious subject in India 
and unfortunately, there are no public watchdog agencies 
that can nail down noise offenders. The noise level in many
 industries is unbearable but corrupt officials look the 
other way and the industrialists go scot-free. Nowadays,
 public awareness about pollution has gone up significantly
 and politicians and officials can ignore the public 
sentiments at their own peril. But awareness about noise
 pollution is yet to gain currency in India. 
And as you rightly said, capitalists pay more attention 
to machine health monitoring than that of the operators.
 (As I said, after a few hours in the test bed, I feel very
 irritated and find it difficult to sleep. The roaring in 
the ears persists for days.)
Another important danger is lurking, that of electromagnetic
 pollution. The other day, we, the engineers of our company 
had a long discussion with a representative of IEC and we 
wanted to know, why there are no standards limiting 
pollution due to harmonic currents in Industries. Of course
 there are well laid out standards about limiting 
electromagnetic radiations. You see, most industries 
nowadays use thyristors to convert AC current to DC and 
in the process, higher frequency currents (electro-magnetic
 noise) are generated. These harmonics severely degrade the 
quality of power in the electrical grid and cause extensive 
damage to equipment connected to the grids. Unless these 
harmonics are suppressed using active or passive harmonic 
filters, public and home electric facilities will have to 
face serious damages.
“do nukes tend to run quiter or louder than (or the same 
as) carbon-fired plants?’
Reply: Les, the noise in a power plant is mainly generated 
by rotating machinery such as turbine-generators, pumps and
 motors and exhaust fans. These equipment are required to 
run a power plant, whether it is nuclear powered or coal/
 oil fired. Hence, the noise inside the turbine hall is of
 the same level for all types of power plants.

Vijaya Kumar Marla

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