S.No Name of item Period Action needed
1. Chlorine Leakage Daily Inspected & take necessary action
2. Pebbles in tower 15 days Clean with water
3. Calcium chloride 1 month or earlier if shape is changes Replace
4. Orifice 1 Month Clean with trichloroethene
5. Stop valve & regulating valve 3 Months Clean with trichloroethene
6. Diaphragm 3 Months Clean with trichloroethene
7. Manometer 3 Months Clean with trichloroethene
9. Gasket 3 Months Calibrate
10. Sleeves 3 Months Replace
11. Filter 3 Months Clean or replace
12. Pressure gauge  3 Months Inspect & calibrate if necessary 
13. Injector 3 Months Clean with matter
14. Tube 6 Months Replace
15. Nut bolt 12 Months Replace
16. Sulphuric acid 12 Months Replace
17. Rubber hose 12 Months Replace


S. No Name of item Period Action needed
1. Chlorine leakage through fittings etc. Daily Inspect and take necessary action
2. Chlorine leak detector  & Exhaust fans Daily Inspect and take necessary action
3. Safety equipment & Breathing apparatus Weekly Inspect and take necessary action
4. Chlorine neutralization system  Weekly Inspect and take necessary action
5. Water pump 3 Months Inspect and take necessary action
6. Chlorine gas filter 6 Months Replace filter element
7. Sedimentation trap 6 Months Clean
8. Rota meter tube & metering orifice  6 Months Clean
9. Wind cock 6 Months Replace
10. Gas header of valves 1 year Replace
11. Stem & seal of valves 1 year Clean 
12. Injector throat 1 year Clean with mild HCL & then with water 
13. Lifting tackle/crane 1 year   Inspect and take  necessary action 
14. Copper tubing between header & cylinder 1 year or screeching sound  is heard on bending  Replace
15. Header System After every 250 Tons  passing of chlorine Clean with water  & dry it
16. Springs in the valves 2 years Replace
17. Pressure gauges &  pressure switches 5 years Replace
18. Diagram in spring loaded value  5 years Replace
19. Joints  Whenever opened Replace gasket with new one. Wire brush the thread & use  Teflon tape for lubricant
20. Evaporator vessel 250 tons of chlorine passage Clean


S. No. Description  Pressure Type Chlorinator  Vacuum Type Chlorinator
Dry feed Aqueous  solution feedsolution feed
  Gravity feed Injector Solutioniser  With Differential vacuum regulator Sonic flow type
1. Rate of feed (max) 230 kg/d 230kg/d 230kg/d 4800kg/d 240 kg/d
2. Water requirement per kg of chlorine (min) Nil 1500 lit Less than 1500 lit. but more than 300 lit. 300 lit. 300 lit
3. Accuracy Low. Low. Low High High
4. Flow meter Manometer Manometer Manometer Rotameter Rotameter
5. Pressure at point of application 0.7 kg/cm2 (max) 0.7 kg/cm2 (max) More than 0.7 kg/cm2 More than 0.7 kg/cm2 More than 0.7 kg/cm2
6. Energy requirement Low Low Low  Moderate Moderate High
7. Maintenance  Extensive Extensive Extensive Moderate Less
8. Status Not in  Not in Not in In production  In production
9. Remarks Not suitable below 10degrees C water. It is used when quality of making solution is not good. It is less safe. Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree centigrade. It is used when quality of water for making solution is good. It is less safe Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree Centigrade it is used when quality of water for making solution is good. It is more safe Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree centigrade. It is used when quality of water for making solution is good. It is less safe Suitable below 10 degree Centigrade provided water for making the solution is beyond 10 degree centigrade. It is used when quality of water for making solution is good. It is less safe



Sl No Facts Reasons Remedy


Chlorine is supplied in liquid form under pressure & it requires heat for converting

It occupies less space

Proper ventilation and proper handling


It is not poisonous but irritant

If forms corrosive acid with body moisture and hence inhalation can cause respiratory injury raging from irritation to death depending upon its inhalation.

Use breathing apparatus.


Dry gas is not corrosive but wet gas is highly corrosive

It forms acid with water

Do not use water on leaking container.


It is neither flammable nor explosive but supports combustion of carbon steel at 251oC.

Containers are made up of carbon steel.

Do not carry out welding work on chlorine containers or piping unless purged out.


Gas combines with ammonia & Forms white smoke,

White smoke detects chlorine leak.

Use for chlorine leakage through the system


Liquid chlorine has large coefficient of expansion.

If the container is filled with filling of 1:19 complete container will be occupied by liquid chlorine at 84o C and hydrostatic rupture may take place.

Do not place the container near the fire or source of heat.


Vapour pressure increases with temperature rise.

Container may rupture due to rise in pressure

Do not place the container near the fire or source heat.


Gas is 2.5 times heavier than air.

Leaked chlorine settles at the ground level

Install exhaust fans at ground level & information the public to take higher level during chlorine leakages.


It is slightly soluble in water but it gets absorbed in caustic soda, soda ash and hydrated lime.

During reaction with caustic soda. Soda ash & hydrated lime heat evolved.

Use soda ash, caustic soda or hydrated lime for neutralization of chlorine. Do not use water for neutralization purpose. Do not push container into solution


Liquid leaks 15 times more than the gas.

It is because of viscosity difference well as different laws of gas and liquid.

Turn the leaking container such as to allow leakage in gaseous form.


Chlorine forms hydrate with water at temperature below 9.4O C

Solid layer is formed

In the case of liquid leak if chilled water is sprayed on the top a solid layer formation will reduce the rate of evaporation of chlorine.


It is dangerous with ammonia gas. Hydrogen, turpentine and hydrocarbon as reactions with these are explosive; powdered metal may cause fire in chlorine

Fire may start in storage of chlorine

Avoid storage of these materials in the chlorine storage. Do not lubricate the valves.


S.No. Equpipment Material
1. Piping Rigid Seamless carbon steel ASTM A 106 grade ‘B’ schedule 80 or equivalent BIS- 1030-1974
2. For gas below atmospheric  pressure Rigid uPVC (for under shed), polyethylene tube, HDPE (outside shed).
3. Globe valves Body : Forged carbon steel Trim : monel or hastelloy ‘C’
Stuffing box : PTFE or graphite packing.
4. Ball valves Body & end piece: Forged carbon steel, ASTM A 105 or  equivalent IS
Seat : PTFE
Ball : Monel
5. Springs Tantalum alloy. Hastelloy
6. Gasket Lead containing 2 to 4% antimony or bonded asbestos.
7. Chlorimator Vacuum Regulator body : Carbon Steel
Regulator diaphragm : FLUON, FEP, Cabinet: FRP
‘O’ ring & gaskets : Fluorocarbon lead oxide (litharge cured) viton
8. Pressure gauge Diaphragm: silver, tantalum, hastelloy, monel alloy Liquid: fluorocarbon, (silicon oil) fluorolube ‘MO’10
9. Differential Regulator Body : U pVC , ABS , ebonite, PVDF
10. Pressure relief valve Body: uPVC, ABS, ebonite, PVDF Stem: Ag, hastelloy, monel
11. Injector Block: ebonite or PVC, ABS
12. Evaporator     Vessel: boiler quality steel
13. Rupture disc Silver : monel, tantalum, hastelloy, “C”
14. Rotameter  Glass : borosilicate Float : PTFE, tatalum, hastelloy, glass
15. Filter media Glass wool
16. Diffuser & solution line  Rigid UPVC saran or rubber lined steel, HDPE, uatural rubber , hose.
17. Pressure reducting valve Body: Ductile cast iron
Diaphragm: FPM (Viton), ECTFE/FEP
Plugs: silver or tantalum, hastelloy
Seats: PTFE
18. Check valve springs Tantalloy/hastelloy
19. Non permanent joints Mixture of linseed oil and white lead or mixture of linseed oil and graphite or Teflon tape.
20. Permanent Joints Glycerine & litharge
21. Screws Monel & stainless steel.


Trouble Cause Remedy
1. Required gas follow not achieved at start up. a. Insufficient ejector vacuum caused by insufficient water supply by pressure or excessive back pressure.
b. Leakage at vacuum line connection at outlet from flow meter, rate control valve, differential from flow meter differential pressure regulator, and/or inlet to ejector. c. vaccum lines (s) flexible crimped.
a. Refer to Trouble at S.No.6

b. Inspect each connections and remake if necessary c. Replace vacuum tubing and arrange line (s) to eliminate crimping.
2. Required gas flow rate is not achieved on startup following an extended period of shutdown. a. Insufficient ejector vacuum.
b. Leakage at vacuum line connection at outlet of flow meter, rate control valve, differential pressure regulator or inlet to ejector.
c. vacuum line (s), if flexible, crimped.
a. Refer to Trouble at 6
b. Inspect each connection and remake if necessary.

c. Replace vacuum tubing and arrange line(s) to eliminate crimping.
3. Flow meter float observed bouncing and/or maximum gas flow cannot be achieved during normal operations. a. Gas inlet filter of vacuum regulator dirty.
b. Rate valve dirty.
c. Flow meter dirty.
d. Ejector water supply pressure fluctuating too wide (float bounce) or insufficient ejector vacuum
a. Replace gas inlet filter assembly.
b. Clean rate valve.
c. Clean flow meter
d. Correct water supply pressure as necessary.
4. Flow meter fails to indicate gas flow during normal operation but there is no out –of-gas indication a. Rate valve plugged
b. Gas flow meter plugged
c. vacuum lines, if flexible, crimped.
a. Clean rate valve.
b. Clean gas flowmeter.
c. Replace vacuum tubing and re-arrange lines to eliminate crimping.
5. No gas indication during normal operation a. gas valve(s) closed.
b. Gas supply exhausted.
c. Clogging of filter in vacuum regulator.
a. Open gas supply valves.
b. Replenish gas supply.
c. Replace filter.
6. Insufficient ejector vacuum a. Y-strainer in water supply line is dirty reducing available supply pressure
b. Back pressure is greater than value listed for one of the following reasons;
i) solution valve, if present, not fully open.
ii) Solution line, present , partially blocked.
iii) back pressure at point of application has increased above its original valve.
c. Ejector nozzle and/or throat dirty.
a. Clean Y-strainer.
b. Open solution valve, clean solution line.
7. Loss of gas feed  a. Dirty or plugged ejector nozzle.
b. Insufficient water pressure to operate ejector.
c. No gas supply.
a. Check for vacuum in ejector clean nozzle.
b. Provide proper water pressure
c. Replenish gas supply.
8. Flooded feeder Dirt lodged on the ejector check valve seat Clean or replace seat or o-ring.


BS:1500::For tonners

IS:7681::Specification for welded low carbon steel gas cylinders for  chlorine gas.

IS:3224::Specification for  valve fittings for compressed gas cylinders.

IS:4263::Code of practice for chlorine

IS:10553::Parts I & II: Requirements for chlorination equipment

IS:5844::Recommendations for hydrostatic stretch testing of compressed gas cylinders.

IS:4379::Identification of contents of industrial gas cylinders.

IS:646::Specification for  liquid chlorine

IS:8198 part 6::Code of practice for steel cylinders for liquified chlorine gas

IS:5845::Code of practice for visual inspection of low pressure welded steel gas cylinders in use.

IS:8868::Periodical inspection interval of gas cylinders in use

IS:9200::Methods of disposal of unserviceable compressed gas cylinders

IS:5903::Recommendation for safety devices for gas cylinders

IS:3710::Filling ratios for low pressure liquifiable gases contained in cylinders.