The document describes various major instruments used in environmental engineering laboratories, detailing their functions, operational parameters, and accuracy. Key instruments include a BOD incubator for microbial growth, COD digestion apparatus for chemical oxygen demand testing, and various samplers for air quality measurement. Additional equipment such as turbidity meters, spectrophotometers, and muffle furnaces are also listed, emphasizing their temperature ranges and usage in environmental testing.

1. Environmental
Engineering Lab
Major Instruments

2. BOD Incubator
•The BOD incubator provides the
required temperature for the growth
of microorganisms and allows us to
perform the BOD testing. The
temperature, humidity, and other
environmental conditions can be
regulated at optimal levels.
Insulation between the inner and
outer walls is done with 75mm thick
glass wool to prevent any heat loss.
The temperature range is from 5˚C to
60˚C. Temperature is maintained with
an accuracy of 0.5°C.

3. COD Digestion
Apparatus
•COD Digestion Apparatus determines Chemical
Oxygen Demand of effluents like wastewater,
industrial water, and sewage. A working temperature
of 150°C and maximum temperature of 250°C can be
operated on 230 volts, 50 Hz, and Single phase.

4. High Volume Air Sampler (PM100), HVS-
4
•The high-volume sampler is used to collect TSP
samples. The high-volume sampler draws a large
known air volume through a pre-weighed filter for 24
hours. The flow control accuracy is 2% of the set
value. It can store data of 10 samples in a non-
volatile memory for subsequent retrieval and
analysis. The Flow Setting Range is 0.6 to 1.8
m3
/minute.

5. Respirable Dust (PM10)
Sampler APM 460
•The respirable dust sampler is used to
collect respirable suspended particulate
matter up to as small as 0.1 microns in
size. It is also used to monitor cement
dust, metal fumes, silica and asbestos
fibers found in cement plants and
factories. The measurement of respirable
particulate matter can be done with an
accuracy of +/-2.0%. The flow rate is 0.9 to
1.4m3
/min. A cyclone is used for
fractionating the dust into two fractions.
PM10 dust is accumulated on the filter
paper while the coarse dust is collected in
a cup placed under the cyclone.

6. PM2.5 Sampler APM 550
Mini
•Fine particulate matter (FPM) consists of solid
particles that are small enough to remain suspended
in the atmosphere for extended periods of time. The
Fine Particulate Sampler consists of two sections: a.
the air inlet and impactor assembly, b. the main
instrument case housing the WINS impactor, filter
holder, flow meter and pump unit. The lower
detection limit of the mass concentration
measurement is estimated to be approx. 2μg/m3
.

7. Gaseous Sampling
Attachment APM 411
•Gaseous sampling attachment has a few advantages: easy
installation of impingers, no heating up of absorbing solutions due
to heat from the blower, provision for ice or cold-water bath around
impingers for effective absorption of gases, taking in impinger tray
directly to the laboratory for safer transit of glass impingers. It has a
flow rate of 0.3 to 3 LPM +/-2% accuracy.

8. Turbidity Meter
•This apparatus is used for measuring the turbidity of
a liquid by determining the degree to which particles
suspended in the solution decrease the intensity of
light lost as a beam is passed through it. It ranges
from 0 to 1000 NTU. It has a resolution of 0.01 NTU.

9. Hot Air Oven
•This apparatus sterilizes the product at
a particular time under specific
conditions like humidity, pressure, and
temperature. It has a double-walled
inner chamber SS 304, outer CRC powder
coated, 65 mm thick glass wool
insulation, and 80/20 nichrome heating
elements placed under ribs at the
bottom and sides for uniform heat
distribution. The temperature range is
50˚C to 250˚C. It has auto-tune dual
display digital, forced air circulation.

10. Five Digit Weighing
Scale
•This instrument is used for the
accurate measurement of the
weight of materials. This weighing
scale has built-in calibration
features that help ensure accuracy
and precision. It has a capacity of
300gm and an accuracy of
0.001gm.

11. Water Bath
•This apparatus is used for carrying
out tests at a constant required
temperature. The water bath is
made of a stainless steel tank of
heavy gauge, soldered at all the
joints, and heavily insulated. The
temperature ranges between 0°C
to 110°C. The temperature
accuracy is ± 2.0°C, and the
resolution is 0.1°C.

12. UV
Spectrophotometer
•This apparatus is used as a
quantitative technique to measure
how much a chemical substance
absorbs light. It is a microcontroller-
based instrument with a wavelength
range of 340nm to 990nm. It offers a
spectral bandwidth of 5nm over the
entire range. Measurement reading
of %Transmittance/ Absorbance/
Concentration/ K-factor is displayed
digitally as per the selected mode. It
provides an accuracy of ± 2.0nm for
wavelength. And for photometric the
accuracy is ± 0.005Abs at 1.0 Abs.

13. Desiccators
•The desiccator is used for drying samples
under atmospheric pressure or vacuum
pressure. These can also protect hygroscopic
chemicals, filter papers, beakers and samples
from dust and moisture in the air. The
desiccator is of 300mm diameter.

14. Lutron Carbon Monoxide
Meter Model GCO-2008
•These detectors are designed to measure the
ambient concentration of carbon monoxide in ppm.
The CO range from 0 to 1,000 ppm. The operability
temperature range is 0 to 50 °C.

15. Sound Level Meter (SLM
109)
•This apparatus can be used for acoustic measurements. It is commonly a
hand-held instrument with a microphone. The measurement range is 30
dB to 140 dB, with an accuracy of ± 1.0 dB and a resolution of 0.1 dB.

16. Magnetic
Stirrer
•This apparatus is used to
agitate liquids to speed up
the reactions or enhance
mixtures. It has a capacity
of 2 liters and works
efficiently on voltage of
230V.

17. Low Flow VOC Sampler
•The VOC sampler can be used to collect air samples
in Tedlar bags. It uses a digital flow meter to
accurately measure 10 to 500ml/min of low flow
rates. The flow control is continuously adjustable
with a precision needle valve.

18. pH Meter
•This instrument is used to measure hydrogen ion
activity in solutions. The degree of hydrogen ion
activity is ultimately expressed as pH level, which
generally ranges from 1 to 14. The pH resolution is
0.01 pH. The pH accuracy is ±0.02 pH. The
temperature range is - 5.0 to 80.0°C.

19. Conductivity – TDS Meter
•The conductivity meter is used to measure the specific conductivity
of a solution using a conductivity cell and TDS in ppt. The
conductivity measurement range is from 20 µ MHO to 200 m MHO
and TDS measurement range is from 2 ppt to 200 ppm. The
measurement accuracy is ± 1%.

20. Conductivity – TDS Meter
•The conductivity meter is used to measure the specific conductivity
of a solution using a conductivity cell and TDS in ppt. The
conductivity measurement range is from 20 µ MHO to 200 m MHO
and TDS measurement range is from 2 ppt to 200 ppm. The
measurement accuracy is ± 1%.

21. Muffle Furnace
•The equipment is used
to heat materials to
extremely high
temperatures whilst
isolating them from fuel
and the byproducts of
combustion from the
heat source. The
temperature ranges from
ambient to 1150°C.