Safety for Treatment Operators

Chlorine is an effective and economical germ killer situations. that is used to destroy and deactivate a wide range Chlorine can of dangerous germs in homes, hospitals, swimming sometimes react pools, hotels, restaurants and other public places. explosively in contact with oil Chlorine is supplied in three basic forms: and grease or • —a liquid commonly known organic materials, as such as wood • —a powder or tablet and rags. • Chlorine gas—container sizes range from 150 lb People can be cylinders to rail cars seriously injured Due to its inherent hazards, operators when chlorine should be trained in the safe use, handling and is improperly mixed with other chemicals, especially storage of chlorine. This training should include the or acidic materials. In a water treatment plant, dangers of bulk chlorine use, transportation labeling this mixing usually occurs by accident – for example, requirements and equipment safeguards that prevent when a tank truck of acidic chemicals is unloaded into chlorine overexposure. the (bleach) storage tank. Some common acidic chemicals found at water and Treatment wastewater plants include ferric , ferric , Before cities began routinely treating drinking water ferrous sulfate, ferrous chloride (pickle liquor), aluminum with chlorine, thousands of U.S. residents died each sulfate (alum), aluminum chloride, hydrochloric , year due to , , hepatitis A and and phosphoric acid. Under the right . Drinking water chlorination and circumstances, these chemicals can react with sodium have helped to virtually eliminate these diseases in hypochlorite to release hazardous chlorine gas. the U.S. and other developed countries. During the treatment process, chlorine is added to drinking Several steps can be taken to prevent chlorine-related water as elemental chlorine (chlorine gas), sodium accidents. hypochlorite solution or dry calcium hypochlorite. • Extensive operator training—Government Almost all U.S. systems that disinfect their water use regulations require that only specified operators some type of chlorine-based process, either alone or highly trained in the unloading process should be in combination with other . assigned the duty of accepting tank truck or tank car deliveries. Potential Dangers to Bulk Chlorine Users • Secured tank loading lines—Prevent truckers Chlorine presents several hazards to users. Elemental from unloading without supervision by installing chlorine (chlorine gas) is a respiratory irritant. It can blind flanges or caps equipped with a padlock. irritate mucous membranes such as the eyes, nose and throat and in extreme cases, breathing chlorine gas can cause respiratory collapse or lung failure, possibly resulting in death. Skin or eye contact with Continued liquid chlorine will cause chemical burns or frostbite. Though chlorine is not normally considered explosive or flammable, it will support combustion in certain www.emcins.com Chlorine Safety for Water Treatment Operators

• Visually define which line is which—Use color Direct mounted vacuum chlorinators—These coding and labeling to differentiate different devices attach directly to the cylinder or the vapor process lines and fittings. You can also change (upper) valve on a container. They require a vacuum the fittings on the loading lines to different sizes in the system to operate. If the vacuum is lost due or types for each line. to either a break in the system or the loss of water • Checklist—Create a checklist that your authorized flow through the venturi injector, then the vacuum operator must complete before accepting a chlorinator will stop the flow of gas. chemical delivery. Items to include: Atmospheric monitoring equipment for chlorine—  Confirm the name of the chemical This equipment can be used to detect leaks and  Review the shipping and the placards monitor chlorine levels. Fixed area detectors are not of the truck or tank car intended to monitor personnel exposure or to quantify  Confirm that proper PPE is being used leaks in the absence of other input. Many states and  Confirm that the volume being delivered does local municipalities have established rules that require not exceed the storage capacity the use of these monitors for specific situations. You can help truck drivers avoid mistakes by placing Acid detecting paint—This paint changes color from signs on sodium hypochlorite unloading lines. Keep yellow to bright when it is exposed to acidic gases signs brief and to the point. Signs should be large like chlorine. The paint returns to its normal color after enough to be visible from at least 10 feet away. Storage the leak is stopped and the leak site is neutralized. sites should consider placing stickers with the same Chlorine and Water System Security wording on the actual sodium hypochlorite piping. The Department of Homeland Security has issued Chemical Facility Anti-Terrorism Standards for any Sodium Hypochlorite Only facility that manufactures, uses, stores or distributes certain chemicals at or above a specified quantity—this (Bleach) includes chlorine. Visit the Department of Homeland Additional Safety Devices and Information Security’s website to learn more about how your for Packaged Chlorine Users facility is affected by these standards. Emergency valve closure systems—Equip systems with valves and/or actuators that will close automatically, stopping the flow of chlorine. These For Additional Information units should only be used to close valves in an Chlorine Chemical Council: www.c3.org emergency—not as a routine part of your operation. The Chlorine Institute: www.chlorineinstitute.org Line pressure warning system—Chlorine release can Centers for Disease Control: www.cdc.gov occur when a container is disconnected while the • Emergency Preparedness and line is still under pressure and/or the container valve Response – Facts About Chlorine did not close properly. Consider installing a pressure sensing device in the line to make sure that the Department of Homeland Security: www.dhs.gov chlorine line is depressurized before disconnecting. • Critical Infrastructure – Chemical Security AWC II, Inc.: www.awc-2.com • Acid/base Detecting Products

Home Office: 717 Mulberry • Des Moines, IA 50309 • 800-447-2295 • www.emcins.com

Disclaimer: This material is designed and intended for general information purposes only, and is not intended, nor shall be construed or relied upon, as specific legal advice. ©Copyright Employers Mutual Casualty Company 2010. All rights reserved. Image ©2010 JupiterImages Corporation. 6165 (10-10)