3. environment , nutrition, demography

Potable water

0 coliforms / 100 ml water

Purest form of water

Rain water (very soft H2O)

Daily water supply in urban areas rural areas

Urban: 150-200L/ capita/ day

Rural: 40-60L / capita/ day

Safe yield of water source

👉 Yield adequate for 95% of the year

Problem habitations

1.6–100–15

1. Water source NOT within:
   

   • 1.6 km (plains)

   • 100 m elevation (hilly)

Water depth:

• >15 meters

Water washed

Saaf safai ni rkhna = washed

Scabbed , trachoma infective , conjunctivitis

Water based disease

Pani se transmit

Cyclops for Guinea worm transmission

Snails for schistosomiasis

Water borne diseases

Borne = born to drink

Ganda pani pine se

GI infection, typhoid, cholera

anopheles - which water

Clean H2O

Culex -

Dirty H2O

Aedes

Artificial collection of H2O

Best method to disinfect H2O

Boiling

Does boiling have residual protection?

No

Best residual property water purification method

Chlorination

Chlorine ONLY has residual property

2nd best method to disinfect water

Chlorination

MC used form of chlorine

Bleaching powder

100g of bleaching powder releases =?

33g free chlorine

Main disinfecting action in chlorination?

HOCl (hypochlorous acid)

👉 HOCl (Hypochlorous acid) = HerO of ChLorine

Chlorine works best @ pH= ?

7

Horrocks apparatus is used for?

👉 Horrock’s apparatus = chlorine demand of water

• 6 cups method

• Indicator = starch iodide

• Blue color = endpoint

2n grams of bleaching powder will disinfect 455L of H2O

How much bleaching powder is required to disinfect 1000L water

2.5g

Break point chlorination

A Point where:

• Chlorine demand satisfied

• Some Extra chlorine added = free residual chlorine

ideas residual chlorine in

Drinking water

Post pandemic

Swimming pool

To kill cyclops/polio

CONTACT PERIOD: 1 hr

1. Drinking water:
   👉 0.5 mg/L for 1 hr

2. Post-epidemic:
   👉 0.7 mg/L

3. Swimming pool:
   👉 1 mg/L

4. To kill cyclops/polio:
   👉 2 mg/L

0.5 p peena , 1 p pool, 2 p polio ko roko

0.5 mg chlorine tablet disinfects?

20L water

WHO Drinking water criteria

Turbidity : 5 NTU

Color: colorless 15TCU /5 hozen unit

Taste& odor : absent

pH: 6.5-8.5

5–15–6.5-8.5

OT test

tells FREE chlorine separately - YES

tells COMBINED chlorine separately - NO

Tells total chlorine

OTA test

Can detect both FREE & COMBINED chlorine separately

Not affected by: manganese , Mg, Iron

1. Yellow color in first 10–15 sec

2. After 5 min

1. Free chlorine

2. Free + Combined

Most effective water treatment in rural areas

Chlorination of water

std chloride in water

200 mg/l

Max : 600mg/l

Permissible harness of water

150-300mg/l

Softening water is recommended @ 150mg/l

Permissible Total dissolved solids (TDS)

<600mg/l

Permissible level : <1000mg/l

Fluoride permissible in water

0.5-0.8mg/l

Nitrates permissible in water

<50mg/l

If high: Indicates remote/long standing contamination of water

NiteRATE: rate old

Permissible nitrite in water

Upto 3mg/l

High; indicates recent contamination of water

Nite RITE : right now

Lead permissible level in water

0.01mg/l

MOST UNDESIRABLE METAL IN WATER

Alpha nd beta radiological acitivity of water

Alpha: <0.5 Bq/L

Beta: <1 Bq/l

Most reliable indicator of fecal contamination In drinking water

E. Coli

Recent: steptococci

Remote(late): clostridium perfirengens

Recent/ non fecal: klebsiella

Why choose COLIFORMS as indicators of water contamination

1. Present in large numbers in intestine

2. Easily detectable

3. Survive longer

4. Resistant to purification

Screening test for Ecoli in water

Presumptive coliform test

(mc method: multiple tube )

Diagnostic test for Ecoli in water

EIC

E : eijkmann test

I : indole test

C : citrate utilization

Amt of Mercury permissible in water

<0.001mg/l

Arsenic permissible in Water

0.01mg/l

1 meq/L hardness = ?

50mg CaCO3 (50ppm) / L

Temporary hardness of water content

Ca2+ , Mg2+ salts of bicarbonate

Permanent hardness of water contents

CNS

Chlorides

Nitrates

Sulfates

Benefit of hardness of water

Protects from CVD

Softening of water is recommended at?

150-300mg/l or 3-6 meq

Methods to remove TEMPORARY hardness of water

BLSP

BOILING

LIME

SODIUM CARBONATE

PERMUTIT

Methods to remove PERMANENT hardness of water

SB

Sodium carbonate

Base exchange

Hardness of water classification

Most effective & cheapest method of disinfecting wells

Chlorination

Sanitary well

• Protected from contamination

• Continuous safe water

Location : <100 radius ,

From source of contamination : >15m(150ft)

STEP WELL became source of which infestation?

Guinea worm

Primary air pollutants

SO, NO, CO

Directly release in air

Secondary air pollutants

Ground level ozone

Combination of 1° pollutants

Best indicator of air pollution

Sulphur dioxide (SO2)

Indicators of pollution

Smoke/ soiling index

Grit/ dust

Coefficient of haze (smoke+aerosol)

API (air pollution index)

MC and widely distributed air pollutant

CO

CARBON MONOXIDE

Best biological indicator of air pollution

Lichen (life detector in air )

Kata thermometer

THIN BULB

• Cooling power of air

• Air velocity (low)

For thermal COMFORT : DRY & WET KATA measurement

Dry: >6

Wet: >20

Globe thermometer

measure: radiant heat / corrected effective temp

THICK BULB

Tool to measure atmospheric pressure

BAROMETER

Examples of natural ventilation

Perflation & aspiration

Examples of mechanical ventilation

Exhaust ventilation

Plenum ventilation

AC

National air quality monitoring program is under?

Central Pollution Control Board (CPCB)

AQI includes:

SO

NO

CO

H2S

Ammonia (NH3)

Lead

AQI TABLE

NO VERY SEVERE CATEGORY

What causes global warming

Green house gases

Water vapour (highest contributor )

Co2 (2nd highest)

Methane

Ozone

Pyare Climate M Over heat

Pani, co2, methane, ozone

what depletes ozone layer

CFC (chloro fluoro carbon)

Highest contributor to global warming

Water vapour

Co2 - second highest

Kyoto protocol 2005

Release green house gas emission by 90%

Paris agreement

Done for Climate change

Protocols to reduce green house gases Water/ global warming

Kyoto protocol 2005

Paris agreement

GLASGO agreement

Solid waste is called

Refuse (rukha waste)

Liquid waste is called

sewage

Most unsatisfactory method for REFUSE disposal

Dumping

DUMPing someone = WORST thing to do

Refuse examples

Garbage : kitchen waste

Rubbish : paper, plastic

Ash: smoke

End product of solid waste disposal

Manure

For a population of 1000, trench dimensions?

2m deep

1 acre land/ year

Most satisfactory method of refuse disposal

Sanitary landfill/ CONTROLLED tipping

Controlled tipping / sanitary landfill methods:

TAR

TRENCH (best costly)

AREA method

RAMP method (HILLY)

MC used refuse disposal method

AREA METHOD (dilli ka kudedaan)

Disused lands

Refuse disposal method in hilly area

RAMP method

Ramp p chadh k

Incineration disadvantage

Hearing method of waste disposal

Disadv: NO MANURE PRODUCTION

Done when land is NOT available

Composting

Converts waste → manure

Eg: CBI

COMPOSTING

Bangalore method → Anaerobic (bang m saas ni ata)

Indore method → Aerobic (Indore cleanest to sas aega )

Waste disposal method of rural areas

Manure pits

2 pits 1-2 m deep

Waste disposal method for camping

Burial

200 log → 1m deep trench → 1 week

Composition of SEWAGE

99.9% H2O + 0.1% solids

Diff b/w SEWAGE & SULLAGE

Sewage : liquid waste + excreta

SULLAGE : liquid waste - excreta

strength of sewage

BOD (biological o2 demand)

Oxygen used by bacteria (aerobic)

Measured over 5 days at 20°C

COD (chemical o2 demand)

Chemical oxidation

👉 Uses “Potassium dichromate”

BOD Strength parameters

Normal BOD : 100-300mg/L

Strong sewage BOD : >300mg/L

Suspended solids in sewage parameters

N: 100-500mg/l

Strong sewage : >500mg/l

Weak sewage : <100mg/l

1° Rx of sewage

SGS

👉 S → Screening

👉 G → Grit removal

👉 S → Sedimentation

2° treatment of sewage

Aerobic oxidation - biological

1. Trickling filter

2. Activated sludge process (preferred most)

3. Sea outfall

4. River outfall

5. Land Rx / sewage farming

6. OXIDATION PONDS & DITCHES

1. Trickling filter : 2° method of sewage Rx

• Needs large area

• ❌ Not preferred

Most preferred 2° method of treatment of sewage (2°- biological)

• Activated heart of sewage treatment •

Activated sludge process

• Aeration tanks (BUZZ WORD)

• Most preferred

• Takes less space

Oxidation ponds & ditches

Use Photosynthesis to purify sewage (plants in ponds & ditches)

Used in smaller communities

“ day - aero> anaero

Night - anaero> aero