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Safety Toolbox Talk (TBT) on Chlorine handling | Hazards and Risk of Chlorine

 

Safety Toolbox Talk (TBT) on Chlorine handling | Hazards and Risk of Chlorine
Safety Toolbox Talk (TBT) on Chlorine handling

Safety Toolbox Talk (TBT) on Chlorine handling | Hazards and Risk of Chlorine 

This Toolbox talk on Chlorine is helpful for people involved in the handling, storage, and transportation of chlorine. Chlorine is widely used for water purification, textile bleaching, PVC and plastic manufacturing, pulp and paper, in pesticides, pharmaceuticals, cooling water treatment, etc. It can be in gaseous or liquefied form and the liquid to gas conversion ratio is approximately 1: 457.

People involved in the handling, storage and transportation of chlorine are at high risk due to its dangerous properties.

 

Hazardous properties of Chlorine

Chlorine is a strong oxidizer, corrosive, a slightly soluble and toxic gas with a pungent and irritating odor and appears greenish yellow in color.

It is 2.5 times heavier than air and sits at the bottom of the work area.

It is not a combustible gas but when in contact with combustible substances it can cause or support combustion, fire and an explosion.

 

Health Hazard and Risk of Chlorine

Routes of exposure to chlorine are inhalation or contact with eyes and skin. Even in low concentrations, chlorine gas can cause nose, throat and eye irritation. When exposed to higher concentrations, it can cause changes in respiratory rate, coughing, lung damage, and other serious symptoms and serious consequences, including death.

The level of exposure depends on the dose, duration and type of work.

Short Term Exposure: Eye and respiratory irritation, runny nose, sneezing, coughing, choking and chest pain. Severe breathing difficulties, irritated skin, burning sensation, itching, inflammation and blistering if exposed to higher concentrations in a short period. Exposure to higher concentrations can cause death.

Long-term exposure: Tooth corrosion and skin irritation

 

Understanding Chlorine Exposure Risk

Exposure to chlorine gas can cause severe irritation to the eyes, mucous membranes, and skin. The TLV (Threshold Limit Value) for chlorine is 1 ppm, that is, the maximum level that can be safely inhaled on working days for a lifetime, while its lethal dose is 1000 ppm, that is, a person who can die after a few deep breaths.

The odor threshold for chlorine is 0.02 to 0.2 ppm depends on the health status of the people, even some people exposed to a concentration of about 3 ppm in the air, may not smell much as this level is the less detectable odor. Exposure to chlorine concentrations of 3 to 6 ppm can cause a burning sensation in the eyes, nose, and throat. Occasionally, people may get a headache due to sinus irritation.

When the chlorine concentration in the air reaches 4 ppm (maximum), the person can breathe for an hour without serious effects, but when the concentration reaches 40 to 60 ppm, then it is dangerous, and the person can be seriously affected in half an hour .

Prolonged or repeated exposure to chlorine at 5 ppm can cause respiratory problems, inflammation of the mucous membranes of the nose, and corrosion or teeth.

 

Chlorine handling safety measure

During loading and unloading of the filled chlorine container, use the appropriate lifting equipment, make sure the valve cap / protection board is intact. After unloading the container, perform a leak test. Also check for leaks before putting into service.

Use Chlorine  canister mask at the time of leak test.

Check the date of the hydraulic test to verify the validity of the cylinder / tonner and always maintain good access between the container valves.

Stay upwind while loading chlorine containers.

Do not store combustible material, such as sawdust, phosphorus, turpentine, etc. near a chlorine container or other chlorine service fittings.

Do not use grease, oil or lubricant on the cylinder valve.

Ensure adequate availability of caustic solution near the storage area.

Do not transport chlorine containers without protective caps.

Be available in the workplace during the chlorine injection operation.

 

Chlorine Emergency Management

In the event of a fire in the nearby chlorine storage area, the temperature of the container may rise and cause an increase in vapor pressure which may cause the container to rupture.

In the event of a chlorine leak, evacuate the area and assemble at the safe assembly point. Escape the area from crosswind direction.

If you suspect chlorine leak from fittings of storage container, take a stick with cloth bulb at one end, soak it with aqua ammonia and hold it close to the suspected area, if there is leakage, then a white vapour or cloud will appears which indicate the leak point. While doing this leak test, avoid contact of ammonia with brass parts. Use all appropriate PPEs.

A competent person detects the leak with the appropriate personal protective equipment, including a canister mask, or uses a self-contained breathing apparatus if the leak is significant. Chlorine is 2.5 times heavier than air, so it tends to stay close to the ground.

Do not spray water into the leaky container, as it is corrosive, cause exothermic reaction with water and forms HCL, evaporation rate increases, and leakage may get worse.

When the chlorine leaks in such a portion that it escapes in liquid form, you can turn/ rotate the container so that the chlorine gas can escape. This helps reduce the danger.

Use a chlorine kit to stop the leak or divert the leak to the caustic solution tank to neutralize it. If hydrated lime is used, the solution must be continuously agitated to absorb the chlorine.

 

Chlorine Emergency First Aid Procedure

Eye Exposure: Use an eye washer to wash your eyes immediately with a large amount of running water. It is suggested to lift the eyelids occasionally to rinse the eyes completely. Seek immediate medical assistance.

Skin Exposure: Rinse contaminated skin immediately with plenty of water. If exposure is through clothing, remove clothing and immediately flush skin with running water for at least 15 minutes. Seek medical help immediately if irritation persists.

Inhalation Exposure: Remove person immediately to fresh air. In case breathing stops, give artificial respiration. Keep the affected person warm and calm. Seek immediate medical assistance.

 

Toolbox Talk on Chlorine safety should be done before loading, unloading, installing, and using chlorine cylinders, tonner or other types of containers. At the end of the toolbox talk, interactive questions can be asked of participants to ensure positive feedback and a better outcome.




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