PREAMBLE (NOT PART OF THE STANDARD)

In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them.

END OF PREAMBLE (NOT PART OF THE STANDARD)

IS : 4263-1967
(Reaffirmed 1995)

Indian Standard
CODE OF SAFETY FOR CHLORINE

(Seventh Reprint OCTOBER 1997)

UDC 661.41 : 614.8

© Copyright 1967
BUREAU OF INDIAN STANDARDS
MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG
NEW DELHI 110002

Gr 5

November 1967

i ii iii iv 1 2 3 4

Indian Standard
CODE OF SAFETY FOR CHLORINE

Chemical Hazards Sectional Committee, CDC 18

Chairman	Representing
Shri N. S. Mankiker	Directorate General of Factory Advice Service & Labour Institutes (Ministry of Labour, Employment & Rehabilitation), Bombay
Members
Shri J. D. Adhia	Hindustan Organic Chemicals Ltd, Bombay
Shri S. M. Machiraju (Alternate)
Shri S. K. Borkar	Directorate General of Health Services (Ministry of Health), New Delhi
shri P. S. Ramachandran (Alternate)
Shri J. M. Dave	Central Public Health Engineering Research Institute (CSIR), Nagpur
Deputy Director, Traffic (General)	Railway Board (Ministry of Railways), New Delhi
Shri J. M. Guha	Ministry of Petroleum and Chemicals
Dr G. Jayarama Rao (Alternate)
Dr Jagdish Shankar	Atomic Energy Establishment Trombay, Bombay
Shri Joginder Singh	Directorate General of Technical Development, New Delhi
Shri S. N. Lahiri	Department of Explosives (Ministry of Works and Housing)
Shri S. C. Roy (Alternate)
Shri C. C. Maniar	Indian Chemical Manufacturers’ Association, Bombay
Dr V. C. Mankodi	Hindustan Steel Ltd, Ranchi
Dr B. N. Chakravarty (Alternate)
Shri M. N. Khanna (Alternate)
Dr C. N. K. Murthy	Ministry of Defence (DGI)
Shri R. S. Agarwal (Alternate)
Shri Narendra Singh	Ministry of Defence (R & D)
Dr K. J. Balakrishna (Alternate)
Representative	Indian Institute of Petroleum (CSIR), Dehra Dun
Shri M. Venugopal	The Western India Match Company Ltd, Bombay
Dr Sadgopal, Director (Chem)	Director General, ISI (Ex-officio Member)

Secretary
Dr A. K. Bhattacharya
Deputy Director (Chem), ISI

(Continued on page 2)

BUREAU OF INDIAN STANDARDS
MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG
NEW DELHI 110002

1 (Continued from page 1)

Industrial Chemical Hazards Subcommittee, CDC 18 : 4

Convener	Representing
Shri S. R. Bhise	Directorate General of Factory Advice Service & Labour Institutes (Ministry of Labour, Employment & Rehabilitation), Bombay
Members
Shri J. D. Adhia	Hindustan Organic Chemicals Ltd, Bombay
Shri S. M. Machiraju (Alternate)
Shri J. M. Dave	Central Public Health Engineering Research Institute (CSIR), Nagpur
Deputy Director, Traffic (General)	Railway Board (Ministry of Railways)
Dr R. M. Desai	Indian Chemical Manufacturers’ Association, Bombay
Shri O. P. Gupta	Directorate General of Ordnance Factories (Ministry of Defence)
Shri S. C. Das Gupta (Alternate)
Shri S. Jagannathan	Esso Standard Eastern Inc, Bombay
Shri K. V. Vijayaraghavan (Alternate)
Shri Joginder Singh	Directorate General of Technical Development, New Delhi
Shri G. A. Kulkarni	Amar Dye Chem Ltd, Bombay
Shri S. N. Lahiri	Department of Explosives (Ministry of Works and Housing)
Shri S. C. Roy (Alternate)
Dr U. C. Patel	Union Carbide India Limited, Calcutta
Shri K. C. Raghavan	D. Waldie and Company Limited, Calcutta
Dr R. Chatterjee (Alternate)
Shri M. L. Seth	The D. C. M. Chemical Works, New Delhi
Shri L. R. Gautam (Alternate)

Panel for Drafting Safety Codes for Hazardous Chemicals, CDC 18 : 4 : 1

Convener
Shri M. L. Seth	The D. C. M. Chemical Works, New Delhi
Members
Shri L. R. Gautam (Alternate to Shri M. L. Seth)
Shri S. K. Barat	Fertilizer Corporation of India Ltd, Sindri Unit
Shri B. N. Chakravarty	Hindustan Steel Ltd, Ranchi
Dr K. V. Viswanathan Nayar	Fertilizers and Chemicals Travancore Ltd, Udyog Mandal P.O., Kerala State

2

Indian Standard
CODE OF SAFETY FOR CHLORINE

0. FOREWORD

0.1

This Indian Standard was adopted by the Indian Standards Institution on 14 June 1967, after the draft finalized by the Chemical Hazards Sectional Committee had been approved by the Chemical Division Council.

0.2

One of the greatest hazards associated with the use of chlorine is that, in becoming a familiar part of a process, it is often forgotten that it is potentially dangerous. The shipment of liquid chlorine in bulk from manufacturer to consumer involves various handling operations, in which the principal risks are common. These are attributable to its toxicolgical character, physical properties, and chemical reactivity.

0.3

It is important that personnel, engaged in a, chlorine plant or in any activity involving handling of chlorine, should understand the hazardous properties of chlorine and should have a good grasp of the basis of preventive measures. This will make them more conscious about safety which would not be achieved if they are trained to follow certain instructions mechanically.

0.4

In India, chlorine is deemed to be an explosive, when contained in any metal container in a compressed or liquefied state, within the meaning of the Indian Explosives Act, 1884. The filling, possession, transport and importation is governed by the Gas Cylinder Rules, 2004.

1. SCOPE

1.1

This standard prescribes a code of safety concerning hazards relating to chlorine. It describes properties and essential information for the safe handling and use of chlorine.

2. TERMINOLOGY

2.1

For the purpose of this standard, the definitions given in IS : 4155-1966* and IS : 4167-1966†, shall apply.
*Glossary of terms relating to chemicals and radiation hazards and hazards chemicals.
†Glossary of terms relating to air pollution.
3

3. PROPERTIES OF CHLORINE

3.1 General Properties

a)	CAS Number	:	7782-50-5
b)	UN Number	:	1017
c)	UN Class	:	2
d)	Hazchem Code	:	2XE
e)	NFPA Hazard Index
	1) Health	:	3
	2) Flammability	:	0
	3) Reactivity	:	0

3.2 Physical Properties

3.2.1

Some of the important physical properties of chlorine are:

1. Physical State—gas as well as liquid
2. Colour—greenish yellow (gas), clear amber (liquid)
3. Odour—characteristic, suffocating
4. Boiling Point (Liquefying)—34.6°C (1 atm)
5. Freezing (melting) point—−100.98°C (1 atm)
6. Density—3.209 g/1 (1 atm; 0°C)
7. Vapour Pressure—3.617 atm (0°C).

3.2.2

Liquid-Gas Volume Relationship—The weight of one volume of liquid chlorine equals the weight of 457.6 volumes of gas at 0° and 1 atm.

3.2.3

Solubility—Chlorine is soluble in alkalis and only slightly soluble in water, approximately 1 percent at 9.4°C. Above this its solubility decreases with rise in temperature up to the boiling point of water at which it is completely insoluble. Below 9.4°C chlorine hydrate known as ‘Chlorine-ice’ (Cl₂.8H₂O), may crystallise.

3.3 Chemical and Hazardous Properties

3.3.1

Flammability—Neither liquid nor gaseous chlorine is explosive or flammable, but both react readily with many organic substances, usually with the evolution of heat and, in some cases, resulting in explosion. Chlorine is also capable of supporting combustion of certain materials.

3.3.2 Reactivity

3.3.2.1 With metals

1. Dry chlorine reacts with aluminium, arsenic, gold, mercury, selenium, tellurium, tin and titanium. At certain temperatures potassium and sodium burn in dry chlorine. Carbon steel ignites at temperatures above 250°C.
2. Dry chlorine, both gaseous and liquid, may be handled safely in equipment fabricated from iron, steel, stainless steels, Hastelloy ‘C’, Monel, nickel, copper, brass, silver, lead and platinum below 110°C (at temperatures above 65°C, chlorine reacts with steel at an accelerated rate). However, this temperature is considerably lower if the metal or alloy is in finely divided, sponge, or wire form.
3. Titanium, platinum, gold and silver are resistant to wet chlorine. Titanium is resistant to both wet and dry chlorine at temperature below 14°C. Moist chlorine readily reacts with mercury. At low pressure, wet chlorine may be handled in equipment made of glass, porcelain, and chemical stoneware. 4

3.3.2.2

With other elements—Chlorine reacts with most elements under specified conditions. Mixtures of chlorine and hydrogen composed of more than 5 percent of either component may react with explosive violence. It reacts with ammonia, alkalis and alkaline earth metal hydroxides.

3.3.2.3

With inorganic compounds—Chlorine has great affinity for hydrogen and as such, removes hydrogen from some inorganic compounds to form hydrochloric acid. It reacts with ammonia and ammonium compounds to form various mixtures of chloramines and under proper conditions nitrogen trichloride which is explosive. Chlorine reacts readily with lime and caustic soda to form hypochlorites which are well-known bleaching agents. Chlorine reacts with moisture to liberate nascent oxygen and form hydrochloric acid. The following chemical reactions take place between chlorine and lime or caustic soda:

2Ca(OH)₂ + 2C1₂ + 2H₂O = Ca(OCl)₂.4H₂O + CaCl₂
2CaO + 2Cl₂ + 4H₂O = Ca(OCl)₂.4H₂O + CaCl₂
2NaOH + Cl₂ = NaOCl + NaCl + H₂O

These reactions are important because lime and caustic soda solutions are used for handling chlorine leaks.

3.3.2.4

With organic compounds—Chlorine reacts with organic compounds to form chlorinated derivatives and hydrogen chloride. Some of these reactions, particularly those with hydrocarbons, alcohols and ethers may become explosive. Gaseous chlorine, wet or dry, may be used with hard rubber equipment at normal temperatures and pressures. However, neither soft nor hard rubber can be used with liquid chlorine.

4. HAZARDS ASSOCIATED WITH CHLORINE

4.1 Health Hazards

4.1.1

General—Chlorine gas is primarily a respiratory irritant. The characteristic penetrating odour of chlorine gas usually gives warning of its presence. At higher concentration it is visible as greenish yellow gas. The effect of chlorine may become more severe for upto 36 hours of exposure.

4.1.2

Acute Local—Short-duration exposures of skin to high concentrations of chlorine gas is not much irritating or corrosive. But this effect is perceptible only when prolonged exposure is tolerated by the use of respiratory protection. Splashes of liquid chlorine on the eyes, skin and clothing, may cause immediate irritation and chemical burns, and severe damage to body tissues.
5

4.1.3

Acute, Systemic—Chlorine gas is extremely irritating to the mucous memberanes, the eyes and the respiratory tract. If the duration of exposure or the concentration of chlorine-is excessive, it will cause restlessness, throat irritation, sneezing and copious salivation. In extreme cases, lung tissues may be attacked resulting in pulmonary edema. Inhal lowest published toxic concentration TC_L0 is 15 ppm and Inhal lowest published lethal concentration is 430 ppm. The physiological effects of various concentrations of chlorine gas are shown in Table 1.

Table 1 Effect of Chlorine at Various Concentrations
(clause 4.1.3)

SI No.	Effects	Concentration of Chlorine Gas in Air, ppm
(1)	(2)	(3)
i)	TLV-TWA(ACGIH)	0.5
ii)	STEL	1
vi)	Least amount for detectable odour	3.5
iv)	Threshold of irritation	4.0
v)	Noxiousness, impossible to breathe several minutes	5.0
vi)	Concentration causing immediate irritation of throat	15
vii)	Concentration causing cough	30.2
viii)	Concentration dangerous in 30 minutes to 1 h	40-60
ix)	Concentration dangerous for even short exposure	50
x)	Fatal even if the exposure is brief	1000

4.1.3.1

Effect of liquid chlorine by absorption through skin, lungs, or intestinal canal is unknown/but when exposed to normal atmospheric pressure and temperature it vaporises to gas which will produce the effects described in 4.1.2 and 4.1.3.

4.1.4

Chronic (Local and Systemic)—Chlorine gas produces no known cumulative effects. A concentration of 1 ppm of chlorine gas may produce slight symptoms after several hours exposure, but careful examination of workers exposed daily to detectable concentrations reportedly has shown no chronic systemic effects. Local chronic effects have not been clinically demonstrated. Sensitization has not been a problem with chlorine. It has been observed that prolonged exposure to atmospheric chlorine concentration of 5 ppm results in disease of bronchi and a predeposition of tuberculosis while lung studies have shown that concentration of 0.8 to 1 ppm cause permanent, although moderate reduction in pulmonary function. Acne is not unusual in persons exposed for long periods of time to low concentrations of chlorine, and is commonly known as chlorance—Tooth enamel damage may also occur.

4.1.4.1

It should be noted here that several hours exposure in the atmosphere containing chlorine at a concentration below that which can be detected by smell or sight may produce slight irritation. Therefore, suitable means of leak detection should be employed for the protection of persons continuously exposed to chlorine handling operations, especially in confined areas. One of the most effective way of leak detection is the use of aqueous ammonia solution, which produces white fumes in the presence of even slight quantities of chlorine.

4.2 Explosion Hazard

Chlorine reacts spontaneously with hydrogen slowly in the dark but explosively in sunlight or at high temperatures, to
6 form hydrogen chloride. The rate of reaction in an equivalent mixture of the two gases is reportedly increased markedly by the presence of oxygen. This fact is of great importance during the manufacture of chlorine by electrolysis and precautions must be taken to prevent the mixing of hydrogen with chlorine in dangerous proportions which may cause a serious fire and explosion. Regular analysis of chlorine for its hydrogen content is essential. The lower explosive limit of hydrogen-chlorine mixtures varies from 3.1 to 8.1 percent, depending on pressure and other variables.

4.2.1

Hot chlorine gas from electrolytic cells, may sometimes crystallize as chlorine octahydrate (Cl₂.8H₂O) due to sudden cooling and clog the pipe lines resulting in hold up of the gas in the pipe lines and allied equipment. This will cause back pressure inside the cells and escape of chlorine into air or into the hydrogen chamber resulting in explosion.

4.2.2

Since liquid chlorine increases considerably in volume when evaporated, hydrostatic rupture in containers, pipe lines and other equipments may occur due to build up of excessive pressure. Particularly, the danger due to pressure build up in a heated cylinder leading to an explosion is to be noted.

4.3 Fire Hazard

Though the fire hazard, attributable to chlorine, is only moderate, it may react to cause fires or explosions upon contact with turpentine, ether, ammonia gas, illuminating gas, hydrocarbons, hydrogen, powdered metals, saw dust and phosphorus.

5. STORAGE AND HANDLING

5.1 Storage

5.1.1

Cylinders should be stored in an upright position. They should be secured to prevent from falling over. Full and empty cylinders should not be stored together. Ton containers should be stored on their sides. They should not be stacked or racked more than one high.

5.1.2

Storage areas should be remote from, elevators gangways or ventilating systems because, in the event of a chlorine leak, dangerous concentrations of chlorine may spread rapidly.

5.1.3

The storage area should be separate from that in. which other compressed gas containers are stored, and should contain no turpentine, ether, anhydrous ammonia, finely divided metals or other Inflammable, Material. The storage area should be dry, well-ventilated, clean of trash, and protected from external heat sources (steam pipes, etc). Sub-surface areas should be avoided for storing chlorine cylinders.

5.1.4

The valves on cylinders and ton containers should be protected by a stout metal cap securely attached to the cylinder body. This cap should
7 always be kept in place on all containers in storage and at all times except during evacuation of chlorine.

5.2 Handling

5.2.1

Cylinders should never be lifted by means of the metal cap, nor should rope slings, chains or magnetic devices be used. Unloading platforms should preferably be at truck or car-bed level. The ton container should be handled with a suitable cradle with chain slings in combination with a hoist or crane having at least 2 metric tonnes capacity.

5.2.2

Cylinders and ton containers being trucked should be carefully checked, clamped, or otherwise suitably supported to prevent shifting and rolling. They should not be permitted to drop, and no object should be allowed to strike them with force. They should not project beyond the sides or ends of the vehicles in which they are transported.

5.2.3

Using Chlorine From Cylinders—Cylinders normally should be emptied in the gas phase, standing secured in an upright position. If it is necessary to empty them in the liquid phase, they should be partially inverted and clamped securely on a rack set at an angle of above 60° to the horizontal. Connection of containers discharging liquid to a manifold is not recommended.

5.2.3.1

Ton-containers set in a horizontal position, with the valves in a vertical plane, deliver gas from the upper valve and liquid from the lower valve. When emptied in the liquid phase, a vaporizer should normally be used.

5.2.4

The flow of chlorine-gas from any chlorine container depends on the internal pressure which in turn depends on the temperature of the liquid chlorine. Discharge rates may, however, be increased by forced circulation of room-temperature air around the container.

5.2.4.1

If the gas discharge rate from a single container will not meet demand requirements, two or more may be connected to a manifold and discharged simultaneously, or a vaporizer may be used. When discharging through a manifold, care shall be taken that all containers are at the same temperature, particularly when connecting a new container to the manifold. If there is a difference in the temperature of the liquid chlorine, it will be transferred by distillation from the warm to the cool container, and the cooler container may become completely filled with liquid. If this should occur and the container valve remains closed, hydrostatic pressure may cause bursting. For this reason, extra precautions shall be observed when closing valves of containers connected to a manifold. Connection of cylinders or ton containers discharging liquid chlorine to a manifold is not recommended.

5.2.5

A flexible connection between the container and the piping should be used; annealed copper tubing (9.5 mm outside diameter × 0.889 mm
8 wall), suitable for 35.2 kg/cm² service is recommended. A clamp and adapter connector is preferred; if a union connector is used, the threads on the connector shall match the valve outlet thread. (Valve outlet threads are straight threads, not standard taper pipe threads.) A new gasket (lead) should be used when making a connection.

5.2.6

Valves should be opened counter-clockwise with a 9.5 mm square-box wrench not over 152 mm long. If the valve is difficult to open, the packing nut may be struck with the heel of the hand, no other implements ought to be used.

5.2.7

When chlorine is being absorbed in a liquid, proper precautions shall be taken to prevent suck-back of the liquid into the container when it becomes empty (due to a partial vacuum created) ; a barometric leg or vacuum breaking device or both should be used.

6. PACKING AND LABELLING

6.0 General

The packing, labelling, handling, and transportation of chlorine gas, when contained in a metal container in a compressed or liquefied state is governed by the Gas Cylinder Rules, 2004.

6.1 Packing

6.1.1

Hydraulic Test—No cylinder should be filled with chlorine gas unless such cylinder has been, subjected by the person filling it to the hydraulic test specified in Schedule I of the Gas Cylinder Rules, 2004, within the preceding 2 years and has passed that test. Any cylinder which fails to pass the hydraulic test or which for any other reason is found to be unsafe for use should be destroyed or rendered useless by cutting holes in it.

6.1.2

Examination Prior to Filling of Cylinder—Every cylinder should be completely emptied, thoroughly cleaned and dried, before it is passed for filling. It should also be examined externally and so far as practicable internally, for surface defects, corrosion and foreign matter.

6.1.3

Filling Ratios and Working Pressure—Cylinders should not be filled with liquid chlorine in excess of the filling ratio of 1 : 19 as specified in Schedule II. of Gas Cylinder Rules, 2004.

6.1.3.1

The working or internal pressure in the cylinder charged with chlorine should not exceed 19.9 kg/cm² gauge in tropical climates at a maximum of 65°C.

6.2 Marking and Labelling of Cylinders

6.2.1

Every cylinder should be legibly marked with the label as given in Fig. 2 of IS : 1260-1958* and the warning in the following terms should be
*Code of symbols for labelling of dangerous goods.
9 printed in the lower half of the label:

Warning ! CHLORINE !

1. Do not change the colour of this cylinder.
2. This cylinder may not be filled with any gas other than chlorine.
3. This cylinder should be kept cool. It should not be placed near a stove or any other source of heat, nor be exposed to the sun.
4. No oil or similar lubricant should be used on the valves or other fittings of this cylinder.
5. This cylinder should not be stored with any inflammable or explosive material.

7. GENERAL PREVENTIVE MEASURES

7.0

The fundamental steps for safe working conditions in a plant or area where chlorine is produced, stored or processed are:

1. designing of layout of area with due consideration for adequate natural or mechanical ventilation,
2. use of properly selected material for construction of plant and equipment for handling of chlorine,
3. preventive maintenance of all equipment in proper working condition, and
4. availability and use of adequate and suitable personal protective equipment at all times.

7.1 Employee Selection and Training

7.1.1

Employee Selection—Chlorine is particularly irritating to persons afflicted with asthma, certain types of bronchitis, other chronic lung conditions, and irritations of the upper respiratory tract; such persons should not be employed where exposures to chlorine gas might occur. Pre-placement medical examination including a chest X-ray is recommended for all new entrants and follow-up medical examinations at suitable intervals for all workers handling chlorine.

7.1.2

Employee Training—Training classes for both new and old employees should be conducted periodically to keep them conscious and informed of the hazards. There should be periodic drill and instruction regarding location, purpose and use of personal protective equipment, safety showers, eye fountains, first aid kits, etc. They should be cautioned to prevent leaks, avoid inhalation of gas and direct contact with the liquid. They, should be told to report to proper authorities immediately in case of an equipmen failure.
10

7.1.2.1

All workers should be instructed and trained to adopt preventive measures in case of emergency. Such training should include knowledge of emergency, fire fighting equipment, fire alarms, crash shut-down procedures for valves and switches, steps to be taken before starting repairs anywhere in the plant, use of personal protective equipment and first-aid. Regular and surprise drills for the above should be conducted to improve further the training in preventive and emergency aspects.

7.2 Eye Protection

Eye protection devices should always be worn in a chemical plant. If there is danger of contact with liquid chlorine, it is essential to wear a gas mask with a full facepiece.

7.3 Respiratory Protection

A suitable gas mask should be available to every employee involved with chlorine handling. Respiratory protective equipment should be carefully maintained and kept in clean, dry, light-proof cabinets properly protected by paraffined paper or polyethylene bags. Cleaning and inspection by competent person is generally necessary after each occasion on which the apparatus is used and should, in any case, take place at least once a month. Equipment used by more than one person should be sterilized after each use. A defective or. inoperable mask is worse than none at all.

7.3.1

So far as it is possible and consistent with efficient protection and use, the protective equipment should be comfortable to work with.

7.3.2

No person wearing a respirator should enter a chlorine contaminated area unless attended to by an observer who can rescue him in the event of respirator failure or other emergencies.

7.3.3

Respiratory Protective Devices—have moulded flexible facepieces with transparent windows which vary in size and shape. Eye protection is imperative due to the irritating nature of moist chlorine gas or liquid chlorine splashes. Provision for exhaust air is accomplished by various types of valving devices which remain tightly closed during the intake cycle of breathing. Connections between the facepiece and other parts of the apparatus utilize a flexible tube, which permits free head movement. This tubing shall be visually inspected and tested for performance at frequent intervals. If leaks in the facepiece, tube, or tube connections cannot be eliminated by tightening the head straps, the complete facepiece and attached flexible tube shall be replaced.

7.3.4

It is equipped with a cylinder of respirable air carried on the body, and is suitable for high concentrations of chlorine in an oxygen-deficient atmosphere and is preferred means of respiratory protection. Such apparatus operates for a specified length of time.

7.3.5

Industrial Canister-Type Masks—It is equipped with a chlorine or all-purpose canister and is suitable for moderate concentrations of chlorine,
11 provided sufficient oxygen is present. The mask should be used for a relatively short exposure period only. It may not be suitable for use in an emergency. For example, the rupture of a chlorine container coincident with oxygen-consuming fire would clearly indicate the use of a self-contained or supplied-air protective device, since, at that time, the actual chlorine concentration may exceed the safe 1-percent limit and the oxygen content may be less than 16 percent by volume. Under this condition suffocation is likely to result.

7.3.5.1

The canister removes contaminants during inhalation but does not supply oxygen. The wearer must leave the contaminated area immediately on detecting the odour of chlorine or on experiencing dizziness or difficulty in breathing; these are indications that the mask is not functioning properly, that the chlorine concentration is too high, or that sufficient oxygen is not available.

7.3.5.2

Unless the presence of other gases require the use of an all purpose canister, the chlorine canister should be used. The service life of a canister depends on the size of the unit, the chlorine concentration and humidity of the atmosphere to which it is exposed, and the rate of breathing. It usually varies from 15 minutes or less at high concentration up to several hours at very low concentrations. Canisters installed in the mask proper with seals broken to render the unit immediately available, do not retain their chlorine-absorptive capacity and shall be replaced immediately after use or within 1 year in any case.

7.3.5.3

Spare canisters should be stored in a cool, dry, accessible place, with seals intact, and dated so that rotation of new supplies is possible.

7.3.5.4

Exceeding manufacturers recommended limits on maximum non-use shelf life might be hazardous. Regular replacement of over-age canisters, even though unused, is recommended. Canisters should be periodically checked for their efficiency.

7.3.6

Positive Pressure (Blower) Hose Mask—It is equipped with air supplied through a hose from a remote blower and is suitable for high concentrations of chlorine provided conditions will permit safe escape if the air supply fails. This device is suitable in any atmosphere, regardless of the degree of contamination or oxygen deficiency, provided that clean, breathable air can be reached. This device is of the continuous flow type.

7.3.7

Demand-Type Hose Mask—It supplies air to the facepiece (at a rate governed by breathing) of the user only when he inhales. Air supply for this device may be full-sized compressed air ^cylinders or a compressor. As for continuous flow type units, the air supply must be suitable for respiration.

7.3.8

Combination units are available which consist of a self-contained demand air unit with a reinforced, high-pressure hose through which air is supplied to the demand regulator from remote air cylinders or a compressor. In the event that escape is not possible through the path of entry, the air hose
12 may be disconnected and escape made using air supplied by the demand air unit on the user’s back.

7.3.9

The information given above should be abstracted, and put into a form which is not only suitable for instant use in the event of emergency, but which may also be used as the basis for first-aid drill. Regular rehearsals, which include the entire testing procedure and wearing of the equipment, will help to save the life of an employee faced with an emergency.

7.3.10

Prevention From Long-Term Effects—The danger from long-term effects may be minimized by maintaining careful medical supervision of those exposed to the hazard, removing from contact anyone who shows early symptoms of being affected, and by excluding anyone who may be expected to show undue sensitivity by reason of existing bodily defect or disease.

7.3.11

Containers, piping and equipment should be checked for leaks daily. If a leak is detected it should be reported and immediate steps taken to correct the conditions.

8. EMERGENCY MEASURES

8.0 General

Wherever chlorine is handled a potential risk is involved and a serious, emergency might suddenly and unexpectedly occur. Emergency situations should be anticipated, plans established and persons trained to counteract them.

8.1 Handling Leaks

Chlorine leaks always get worse unless they are corrected promptly. Chlorine leaks should be investigated by authorized, trained personnel equipped with suitable gas masks. If the leak is extensive an effort should be made to warn all persons in the path of the gas. Chlorine is heavier than air; therefore persons should be instructed to keep above and upwind of the leak.

8.1.1

Water shall never be used on a chlorine leak as it always makes the leak worse due to the corrosive effect. In addition, heat supplied by even the coldest water to a leaking container causes liquid chlorine to evaporate faster. A leaking container, shall not be immersed or thrown into a body of water as the leak will be aggravated due to the corrosive effect and the container may float when partially full, allowing gas evolution and dispersion at the surface.

8.1.2

Equipment and Piping Leaks—If a leak occurs in equipment in which chlorine is being used, the supply of chlorine shall be shut off and chlorine which is under pressure at the leak shall be disposed off safely.

8.1.2.1

Leaks around valve stems usually may be stopped by tightening the packing nut or gland. If this does not stop the leak, the container valve shall be closed and the chlorine, which is under pressure in the outlet piping, shall, be disposed off. If a container valve does not shut off tight, the outlet
13 cap or plug should be applied. In case of a valve leak on a ton-container, the container shall be rolled so that the valves are in a vertical plane with the leaking valve on top; this is important.

8.1.2.2

If practical, the pressure in the container should be reduced by removing the chlorine as gas (not as liquid) to process or a disposal system. In some cases it may be desirable to move the container to an isolated spot where it will do the least harm.

8.1.3

In case of chlorine leaks, while seeking an escape, or while respiratory equipment is being secured and adjusted, short, shallow breaths should be taken and eyes should be closed as much as possible. It is important to keep above and to the windward side of escaping chlorine gas. All exhaust mechanisms should be turned on immediately. The leaks should be investigated at once by authorized, trained personnel equipped with suitable respiratory protection. All other persons should be kept away from the affected area, until the cause of the leak is discovered and the difficulty corrected. Respiratory protective devices should be located outside the probable area of contamination so that it will be possible to reach them in emergency.

8.1.4

Leaks in Transit—If a chlorine leak develops in transit in a populated area and if the magnitude of the leakage is minor, and no emergency kits are available, excessive quantities of lime should be used to arrest leaking chlorine. If the leakage is extensive, it is advisable, to keep the transporting vehicle moving until open country is reached in order to minimize the hazards. Appropriate emergency measure, as given above, should then be taken as quickly as possible.

8.2 Alkali Absorption

As a regular part of chlorine storage and use, provisions shall be made for emergency disposal of chlorine from leaking cylinders or ton-containers. Chlorine may be absorbed in solutions of caustic soda or soda ash, or in agitated hydrated-lime slurries. Caustic soda is recommended as it absorbs chlorine more readily. The proportions of alkali and water recommended for this purpose are given below:

Chlorine Container Capacity	Caustic Soda and Water		Soda Ash and Water		Hydrated Lime and Water
kg	Weight kg	Volume 1	Weight kg	Volume 1	Weight kg	Volume 1
45	58	182	136	450	58	566
68	90	270	220	680	82	815
900	1 160	3 680	2 720	9 050	1 160	11 350

8.2.1

A suitable tank to hold the solution should be provided in a convenient location. Chlorine gas should be passed into, the solution through
14 an iron pipe or rubber hose properly weighted to hold it under the. surface; the container should not be immersed.

8.3 Emergency Kits

The majority of chlorine suppliers have emergency kits and skilled technicians to use them. These kits may be used to stop most of the leaks in a chlorine cylinder, ton container, etc, and may usually be delivered to consumer plants within a few hours in an emergency. However, it is advisable for the consumers to purchase kits and to train employees in their use.

8.4 Fire

In the event of fire, chlorine containers should be moved from the fire zone immediately. If chlorine containers cannot be moved, water should be applied to cool them provided no chlorine is escaping.

9. FIRST-AID

9.0 General

Suitable notices should be fixed in convenient places regarding first-aid measures. The need for speed in all first-aid shall be impressed on everyone concerned, together with the necessity of avoiding further shock to the patient. All employees should be informed of the urgent necessity in their own interests of reporting immediately for first-aid treatment, all minor accidents and also report any sickness which may be thought to be connected with their employment. Any one overcome by or seriously exposed to chlorine gas should be removed at once to un-contaminated area.

9.1 Inhalation

If breathing has not ceased, the patient should be placed on his back, with head and back elevated, and kept warm, using blankets, if necessary. Rest is essential.

9.1.1

If breathing apparently has ceased, artificial respiration shall be started immediately. The ‘Nielson armlift-back pressure’ method is preferable. A physician shall be called immediately. If oxygen-inhalation apparatus is available, oxygen should be administered by a person authorised for such duty by a physician.

9.1.2

Stimulants rarely are necessary where adequate oxygenation is maintained, and any such drugs for shock treatment should be given only by a physician. Milk may be given in mild cases as a relief from throat irritation. 1 Nothing should ever be given by mouth to an unconscious patient.

9.2 Skin and Clothing

If liquid chlorine or chlorinated water has contaminated skin or clothing, the emergency shower shall be used immediately. Skin areas should be washed with large quantities of soap and water. No attempt shall be made to neutralize chlorine with chemicals. No ointment shall be applied for 24 hours. Contaminated clothing should be removed immediately.
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9.3 Eyes

If eyes have been affected with liquid chlorine or high concentrations of chlorine gas, they shall be flushed immediately with running water for at least 15 minutes. (No attempt shall be made to neutralize with chemicals.) Thereafter, as a first-aid measure, 2 or 3 drops of 0.5-percent solution of pontocaine or other equally effective topical anaesthetic shall be instilled into the eyes. No oils or oily ointment should be used unless prescribed by an eye specialist.

9.4 Ingestion

The swallowing of liquid chlorine is extremely unlikely. However, if a person has swallowed chlorine and is conscious, he should immediately be made to drink copious amounts of lime water, milk of magnesia, or fresh water if the others are not readily available. Sodium bicarbonate shall not be given. The victim may be expected to vomit spontaneously, but no attempt should be made to induce vomiting or to use a stomach tube. A physician shall be called immediately.

9.5 First-Aid Equipment

All employees should be given comprehensive instructions on the use of first-aid equipment mentioned below and any other that may be available with the authorities.

9.5.1

Properly designed emergency showers and eye baths should be provided in convenient locations and they should be properly maintained.

9.5.2

Oxygen administration apparatus should be available in the plant’s first-aid or ambulance room or medical dispensary. Such equipment should be in the charge of a person knowing use of such apparatus in an emergency. The big manufacturers and large scale consumers should train several persons in the use of oxygen administration apparatus and make a trained person available all the time.

9.6 Boxes or Cupboards

distinctly marked with the words ‘First-Aid’ shall be provided in readily accessible positions. These should not contain anything except the prescribed medical appliances and requisites. A list of contents should be fixed to the inside of the box. A sufficient number of persons should be imparted effective training in First-Aid.

10. EQUIPMENT CLEANING AND REPAIRS

10.1

Equipment and tank cleaning and repairs should be under the direction of thoroughly trained personnel.

10.2

Workmen should not attempt to repair chlorine equipment while it is in operation and when piping system is in service.

10.3

Welding, cutting or other work using flame or spark should not be attempted on chlorine lines or containers until purged with steam and then hot-air-dried. As a substitute they may be filled with carbon dioxide provided the line is equipped with a low-pressure safety valve.
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10.4

If pipe sections are to be removed and flanges opened, the lower bolts should be loosened first and although the lines have been purged, care should be exercised to avoid contact with any residual material that drips from the equipment.

10.5

Immediate drying of a chlorine pipe line or container into which water accidently has been introduced or which has been opened for repairs or cleaning is essential if corrosion is to be prevented.

10.6

Workers entering tanks should be equipped with suitable personal protective devices, preferably a self-contained breathing apparatus. Canister mask should not be used unless the oxygen content is periodically determined to be suitable for this purpose. At least one other person should be observing operations from outside the tanks at all times.

10.7

Under no circumstances should a rescuer enter a tank to remove a victim of overexposure without proper respiratory protection, a safety harness and an attached life-line. Another attendant should be available at all times and the rescuer should be in view of the outside attendant at all times or in constant communication with him.
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BUREAU OF INDIAN STANDARDS

Headquarters:
Manak Bhavan, 9 Bahadur Shah Zafar Marg, NEW DELHI 110002
Telephones : 323 0131, 323 3375, 323 9402
Fax : 91 11 3234062, 91 11 3239399, 91 11 3239382
Telegrams : Manaksanstha (Common to all Offices)
Central Laboratory:	Telephone
Plot No. 20/9, Site IV, Sahibabad Industrial Area, Sahibabad 201010	8-77 00 32
Regional Offices:
Central : Manak Bhavan, 9 Bahadur Shah Zafar Marg, NEW DELHI 110002	323 76 17
*Eastern : 1/14 CIT Scheme VII M, V.I.P. Road, Maniktola, CALCUTTA 700054	337 86 62
Northern : SCO 335-336, Sector 34-A, CHANDIGARH 160022	60 38 43
Southern : C.I.T. Campus, IV Cross Road, CHENNAI 600113	235 23 15
†Western : Manakalaya, E9, Behind Marol Telephone Exchange, Andheri (East), MUMBAI 400093	832 92 95
Branch Offices:
‘Pushpak’, Nurmohamed Shaikh Marg, Khanpur, AHMEDABAD 380001	550 13 48
‡Peenya Industrial Area, 1st Stage, Bangalore-Tumkur Road, BANGALORE 560058	839 49 55
Gangotri Complex, 5th Floor, Bhadbhada Road, T.T. Nagar, BHOPAL 462003	55 40 21
Plot No. 62-63, Unit VI, Ganga Nagar, BHUBANESHWAR 751001	40 36 27
Kalaikathir Buildings, 670 Avinashi Road, COIMBATORE 641037	21 01 41
Plot No. 43, Sector 16 A, Mathura Road, FARIDABAD 121001	8-28 88 01
Savitri Complex, 116 G.T. Road, GHAZIABAD 201001	8-71 19 96
53/5 Ward No. 29, R.G. Barua Road, 5th By-lane, GUWAHATI 781003	54 11 37
5-8-56C, L.N. Gupta Marg, Nampally Station Road, HYDERABAD 500001	20 10 83
E-52, Chitaranjan Marg, C-Scheme, JAIPUR 302001	37 29 25
117/418 B, Sarvodaya Nagar, KANPUR 208005	21 68 76
Seth Bhawan, 2nd Floor, Behind Leela Cinema, Naval Kishore Road, LUCKNOW 226001	23 89 23
NIT BUilding, Second Floor, Gokulpat Market, NAGPUR 440010	52 51 71
Patliputra Industrial Estate, PATNA 800013	26 23 05
Institution of Engineers (India) Building 1332 Shivaji Nagar, PUNE 411005	32 36 35
T.C. No. 14/1421, University P. O. Palayam, THIRUVANANTHAPURAM 695034	6 21 17
*Sales Office is at 5 Chowringhee Approach, P.O. Princep Street, CALCUTTA 700072	27 10 85
†Sales Office is at Novelty Chambers, Grant Road, MUMBAI 400007	309 65 28
‡Sales Office is at ‘F’ Block, Unity Building, Narashimaraja Square, BANGALORE 560002	222 39 71

__________________________________
Printed at Pantograph, New Delhi (INDIA).

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