Major sources of noise in furnace operation arises from air inspirators, combustion, side wall vibrations and fluctuation in the process heat load. A 50% increase in fuel firing rate may increase the furnace noise level by about __________ decibels. (A) 3 (B) 30(C) 7 (D) 70

Major sources of noise in furnace operation arises from air inspirators,
combustion, side wall vibrations and fluctuation in the process heat load. A
50% increase in fuel firing rate may increase the furnace noise level by
about __________ decibels.
(A) 3
(B) 30
(C) 7
(D) 70
by

1 Answer

Answer :

(A) 3
by

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Description : Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels. (A) 85 (B) 105 (C) 125 (D) 145

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Description : Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels. (A) 35 (B) 75 (C) 95 (D) 105

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