Noise Level Monitoring & Testing

Work room Noise Exposure Level as per MFR 1963 SCHEDULE XXIV

Operations involving High Noise Levels

Application : This schedule shall apply to all operations in any manufacturing process having high noise level.

Definitions: For the purpose of this schedule.

a) “Noise” means any unwanted sound.

b) “high noise level” means any noise level measured on the A-weighted scale in 90 dB or above.

c) “Decibel” means one-tenth of “Bel” which is the fundamental division of a logarithmic scale used to express the ratio of two specified or implied quantities, the number of “Bels’ denoting such a ratio being the logarithmic to the base of 10 of this ratio). The noise level (or the sound such a ration being the logarithmic to the base of 10 of this ratio. The noise level (or the sound pressure level) corresponds to a reference pressure of 20 x 10 newtons per square meter 00002 or dynes per square centimeter which is the threshold of hearing, that is the lowest sound pressure level necessary to produce the sensation of hearing in average healthy listeners. The decibel in abbreviated form is dB.

d) “Frequency” is the rate of pressure variations expressed in cycles per second or hertz.

e) “DBA” refers to sound level in decibels as measured on a sound level meter operating on the A- weighting network with slow meter response.

f) “A-weighing” means making graded adjustments in the intensities of sound of various frequencies for the purpose of noise measurement, so that the sound pressure level measured by an instrument reflects the actual response of the human ear to the sound measured.

Protection against noise : (1) In every factory, suitable engineering control or administrative measures shall be taken to ensure, so far as is reasonably practicable, that no worker is exposed to sound levels exceeding the maximum permissible noise exposure levels specified in Tables 1 and 2.


Permissible Exposure in case of continuous Noise

Total time of exposure (continuous or a in dBA Number of short term exposures) per Day, in hours. Sound pressure level
8 ... ... ... ... ... 90
6 ... ... ... ... ... 92
4 ... ... ... ... ... 95
3 ... ... ... ... ... 97
2 ... ... ... ... ... 100
11/2 ... ... ... ... ... 102
1 ... ... ... ... ... 105
3/4 ... ... ... ... ... 107
1/2 ... ... ... ... ... 110
1/4 ... ... ... ... ... 115

Notes :

(1) No exposure in excess of 115 dBA is to be permitted.

(2) for any period of exposure failing in between any figure and the next higher or lower figure as indicated in column 1. The permissible sound pressure level is to be determined by extrapolation on a proportionate basis.

Noise Level Monitoring & Testing

Noise or sound level monitoring or measurement is a process to measure the magnitude of Noise in industries and residential area. Data collected from Noise level monitoring & Testing helps us to understand trends and action can be taken to reduce noise pollution. Noise pollution is Low or High-frequency sound that can cause/harm the activity of human life. It can be caused by various industrial Machines, Motor Vehicles and Craft etc. Noise Pollution Monitoring process is a part of Environmental Monitoring & Testing as noise pollution is also increasing exponentially in recent years.

What is Noise Pollution?

Noise pollution is unwanted and unpleasant sound which can deteriorate human health and other living organisms present in the Environment.

Why to Measure Noise at the Workplace?

At workplace machines, traffic, vehicles create occupational noise. Employees and occupants are exposed to this harmful noise. Due to this occupants can face many health problems such as headache, hearing impairment, hypertension, heart problem, annoyance and sleep disorder. to Avoid this situation Perfect Pollucon Services conducts Noise Testing in the company or home to measure high noise within premises. Actions can be taken once the locations and source are identified which are causing the noise. it helps to keep your employee or family safe from Harmful Noise.

Measurement of Noise Level Using Noise Testing Equipment

Sound/Noise level meter equipment measures noise pollution. It consists of several parts, mainly Microphone, Pre-amplifier, frequency weighting, Processor, Display System, communication System and Power Supply. dB(A) Leq denotes the time-weighted average of the level of sound in decibel on scale A which is relatable to human hearing.

A “decibel” is a unit in noise measurement. “A”, in dB (A) Leq, denotes the frequency weighting in the measurement of noise and corresponds to frequency response characteristics of the human ear.

Leq: It is an energy mean of the noise level over a specified period.

Noise level Survey schedule is planned in such a way that it covers the noise generation by normal daytime activities i.e. from 08:00 am to 10:00 pm and a part of nighttime activities i.e. 10:00 pm to 12:00 am (at night).

Due to the increase in noise pollution in recent years, it is recommended to conduct a measurement of noise pollution program on company premises.

Noise level Monitoring & Testing

The answer to the question of how to measure sound lies in Noise level Monitoring or sound Measurement for a particular instance or for 24X7 hrs to analyze trends for better understanding of the environment. these Processes also used in Noise Impact Assessment (We love to do this 😉 ) by Noise level Testing companies. This process is also called as Noise level Measurement.

A) Industrial Noise Measurement

Industrial Noise is the loud sound in industries. In general, it is produced, at every stage in the industry by various aspects like welding, hammering, drilling, blowing, running machinery, motors, sheet metal work, lathe machine work, operation of cranes, grinding, turning, fabricating, forging, compressing, breaking, moulding, steaming, boiling, cooling, heating, venting, painting, pumping, packing, transporting etc. It creates very serious of large-scale noise problems; significantly affect the working people as well as surrounding people.

B) Non-Industrial Noise Measurement

i) Road Traffic Noise:

Road traffic is the most widespread source of the noise. It is directly proportional to the volume of vehicles. Increasing the population is increasing in vehicles and hence increasing of Noise pollution. The major sources of noise in automobiles are exhaust, intake, engine and fan, and tires at high-speed. Noise Level Monitor instrument (or with noise level data logger) measures the noise level.

ii) Residential Noise Measurement

In normal day –to – day activities, various home appliances in our residences produce noise. Some of the major sources are Exhaust Fans, lawn movers, grinders, Fan, Cooling & Heating System, T.V & Music System, motors used for pumping etc.

Noise Level Testing Standards

Limits or noise level standards defined by pollution control board during Day time for Residential Noise < 55 dB and Limits during Night time for Residential Noise < 45 dB

In industry, there are of two types Sound Monitoring & testing or Noise Level Measurement:

  • Ambient Noise level Monitoring
  • In-plant Noise level Monitoring

A) Ambient Noise Level Testing Standards

Ambient Noise level Monitoring or Noise pollution Measurement within the industrial zone at ambient conditions. (e.g. Near Main Gate, Near Canteen, Near Manufacturing plant etc.) As per Central Pollution Control Board (as per Factory act 1948):

Limits or acceptable noise level during Day time for Ambient Noise < 75 dB and Limits during Night time for Ambient Noise < 70 dB.

B) In-plant Noise level Testing Standards

In-plant Noise level means Sound level measurement allocated in the plant. As per Central Pollution Control Board (as per Factory act 1948) Limits for In-plant Noise level < 90 dB.

Noise Monitoring & Testing Company

We are a leading Noise Level Testing Company in India. We have highly trained and highly experienced professionals who can take care of Noise level Monitoring or testing.

Noise level Monitoring Procedure

Noise level measurement procedure are processes which record sound level or acoustic energy level in the specified area. Sound or Noise level meter measures noise in Unit decibel (dB). We will see what are important factors to keep in mind while measuring noise level.

Noise Monitoring / Testing Services

We carry out Sound or Noise Monitoring And Noise Testing services with periodically calibrated instruments which gives you accurate reading with the analysis report.