Chapter 6 chemical

environmental health

1. Module 6: Chemicals in the Workplace Contents Introduction. Chemicals in the Workplace. What chemicals are hazardous ? Classifications of hazardous chemicals How do chemicals enter the body? What are the steps for chemical risk assessment ? Control hierarchy Who should do the risk assessment? What is a Hazcom instruction? Hazard Control and Prevention Managing chemicals Working with Chemicals

2. Introduction Today, almost every business uses chemicals, Even in the cleanest, most modern office , employees are exposed routinely to inks , toners and adhesives not to mention a wide range of materials used in cleaning and maintenance . Exposure to chemicals in the workplace can cause many different types of harm , ranging from mild irritations to cancer .

3. Cont……. Managing chemicals and their associated hazards in the workplace will bring real benefits to a business . In addition to improved employee safety and health, cost savings can be achieved by limiting economic losses through effective work practices such as correct storage , handling , use and disposal procedures. Potential harm to the environment will also be reduced .

4. Chemicals in the Workplace There are 750,000 hazardous chemicals used in the workplace around the world. Chemicals are used for a variety of purposes. Employees must know how to protect themselves from chemical hazards . What is a Hazardous Chemical? A hazardous chemical is any substance that poses a physical or health hazard to you or others in the workplace.

5. What chemicals are hazardous? Any substance, in gas, liquid or solid form, which has the potential to cause harm , is referred to as a hazardous or dangerous substance . Such substances include those :

6. Cont….. Brought directly into the workplace and handled, stored and used for processing (e.g. solvents, cleaning agents, glues, paints ). Generated by a process or work activity (e.g. fumes from welding ). Generated as waste or residue (e.g. fumes from soldering irons, carbon monoxide from exhausts).

7. Cont…….. Substances can be considered hazardous not only because of what they contain (i.e . their chemical ingredients) but because of the form or way in which they are used at the workplace . In addition to their effects on human health , some chemicals also present physical hazards such as the potential to ignite or support combustion of other substances ( oxidizer ) and the potential to explode . The physical, environmental and human hazards of a chemical substance must be considered when conducting a risk assessment in the workplace.

8. Classifications of hazardous chemicals A variety of hazardous chemicals are commonly found in the workplace . It's important to understand the substances that fall under this classification, as they can have an adverse effect on human health and cause harm to property and the environment . Hazardous chemicals Hazardous chemicals are substances that can cause adverse health effects such as poisoning , breathing problems , skin rashes , allergic reactions , cancer , and other health problems from exposure.

9. Cont…….. Many hazardous chemicals are also classified as dangerous goods. These can cause fires, explosions , corrosion , and hazardous reactions if not handled safely . Examples of hazardous chemicals. Paints Drugs Cosmetics Cleaning chemicals. D etergents

10. Cont……. 6. Pesticides 7. Welding fumes 8. Gases 9. Corrosives 10. Chemically reactive or acutely (highly) toxic substances.

11. How do chemicals enter the body? In order for a chemical to become hazardous to a person’s health, it must first contact or enter the body and the chemical must have some biological effect on the body.

12. Absorption Occurs when contact with exposed skin allows a chemical to be absorbed into the body. To prevent absorption, wear proper protective equipment: Chemical gloves Aprons Coveralls

13. Inhalation Can occur when chemicals become airborne in the form of a vapor, dust allowing them to be inhaled into the lungs. To prevent inhaling hazardous chemicals you must select and use proper respiratory protection.

14. Ingestion Can occur when hazardous chemicals are eaten or swallowed. To avoid ingesting hazardous chemicals never Eat Drink Apply make-up Always wash hands after handling chemicals.

15. Examples 1. Acute effects are those that show up immediately after a chemical exposure occurs . A good example of an acute effect is the spillage of acid on the skin – a chemical burn will occur immediately. 2. Chronic effects are those that occur after a significant amount of time passes and usually are the result of multiple exposures over a period of time . Cancer is a typical example of a chronic effect because cancers caused by chemical exposures often do not show up until twenty or more years after the initial exposure .

16. Some common examples of the effects of hazardous chemicals Skin irritation, dermatitis or skin cancer from frequent contact with oils. Injuries to hands and eyes from contact with corrosive liquids . Long-term disability from lung diseases following exposure to dusty environments (e.g. exposure to respirable crystalline silicate ). Death or injury from exposure to toxic fumes (e.g. carbon monoxide ). Cancer causing death many years after first exposure to carcinogens at work (e.g. asbestos).

17. What are the steps for chemical r isk a ssessment ? Chemical risk assessment forms an integral part of controlling health risks in the workplace . There are four main steps involved. Step 1: Make an inventory Chemical inventories are a very important tool and the first step in effective chemical management . Make an inventory of the substances used in your work processes (e.g. solvents) and those generated by the work processes (e.g . dust, residues, waste). It should be designed to systematically identify hazardous substances present in the workplace .

18. Step 2: Collect information Collect information about each substance , i.e. the harm it can do and how this can happen. Safety Data Sheets , which must be provided by the supplier of a chemical, and labels are an important source of information. Step 3: Assess exposure Assess exposure to the identified dangerous substances , looking at the type , intensity , length , frequency and occurrence of exposure to employees , including combined effects of dangerous substances used together and the related risk . Find out if substances have occupational exposure limits (OELs ). Consider any physical or environmental hazards .

19. Step 4: Decide on and implement suitable control measures to hierarchy for exposure control measures to be applied if a risk assessment reveals risks. 1. Elimination of the hazard by changing the process or product. 2. Substitute another, non-hazardous or less dangerous chemical. 3. Where 1 and 2 are not possible , control measures should be implemented to remove or reduce the risks to employees’ health.

20. Control hierarchy 1. Enclosure/isolation of hazard: Design work processes and controls, and use adequate equipment and materials , to reduce the release of dangerous substances (e.g. total or partial enclosure ). 2. Ventilation of area: use , for example , extraction equipment or general ventilation .

21. Cont………… 3. Use personal protective equipment (PPE): where exposure cannot be prevented by other means, use PPE including respirators, safety glasses, gloves, overalls, protective creams and lotions .

22. Further measures include: Chemical emergency procedures: Draw up an emergency plan covering procedures for spillages, first aid, emergency exits etc. Organizational control: through , for example , chemical inventories, labeling , training and consultation of staff, providing risk information using Hazard communication ( Hazcom) instructions , instructions from manufacturers , systems of work and handling procedures , safe storage and transfer.

23. Who should do the risk assessment? In many cases, you and your employees have the best knowledge and understanding of your work processes and are therefore best placed to carry out the risk assessment . If specification of the control measures is not straightforward , or if complex risks have to be assessed , you may need to engage competent specialist expertise to assist in the task.

24. Cont……… The risk assessment must be recorded and made available to employees . The law requires that the control measures are identified in writing (paper or electronic format). The risk assessment should be a ‘living document’ that is reviewed if situations change or if there is reason to think that it is no longer valid .

25. What is a Hazcom instruction? A Hazcom instruction is an important tool in conveying risk information to employees . It should be simple in layout and use easy to understand language . As previously stated, a Safety Data Sheet can be difficult to use for this purpose. A Hazcom instruction should include, as a minimum , the following information.

26. Cont………. Name (substance identification). Hazard identification. Safety measures and safe-handling procedures . Accidental release measures. First aid procedures. Appropriate methods of disposal.

27. Cont……….. It should describe the workplace operation and be signed by the user. Hazcom instructions can also take the form of pictograms to illustrate good work practices.

28. Hazard Control and Prevention The most effective chemical hazard control is prevention. Establishing an effective chemical control program in your facility can reduce or eliminate chemical hazards in food. Successful chemical control program should include: 1. Train employees to follow safe handling and application procedures for sanitation, maintenance or pesticides chemicals .

29. Cont…… 2. Store chemicals in designated areas away from food , ingredients, packaging and food contact surfaces. 3. Make it standard practice for staff, after maintenance, to properly clean and remove all chemical residues from food contact surfaces. 4. Do not use excessive grease or lubricants on equipment. Regularly re-evaluate all procedures to ensure they effectively remove chemicals.

30. Cont…… 5. Ensure chemical containers and measuring tools are clearly labeled or colour coded , and that they are used only for chemicals .

31. Managing chemicals When managing laboratory chemicals, not all risk can be eliminated. However, laboratory safety and security are greatly improved through informed risk assessment and careful risk management. The careful management of a chemical’s life cycle not only minimizes risks to humans and to the environment, but also decreases costs.

32. Storage of highly reactive substances Storage of highly reactive substances Check international, regional, or local building and fire codes to determine the maximum amount of highly reactive chemicals that can be stored in a laboratory. Follow the general guidelines below when storing highly reactive substances. 1. Consider the storage requirements of each highly reactive chemical before bringing it into the laboratory.

33. Cont…… 2. Bring into the laboratory only the quantities of material needed for immediate purposes depending on the materials ). 3. Be sure to label , date , and inventory all highly reactive materials as soon as received. 4. Store highly reactive liquids in container large enough to hold the contents of the bottles . 5. Restrict access to the storage facility.

34. Cont………

35. Working with Chemicals Safe and secure execution of experiments requires work practices that reduce risk and protect the health and safety of laboratory personnel as well as the public and the environment.

36. General Procedures for Working with Hazardous Chemicals. Personal Behavior. 1. Avoid distracting or startling other personnel. 2. Do not allow practical jokes conduct . 3. Use laboratory equipment only for its designated purpose. 4. Review basic safety procedures with all visitors to laboratories where hazardous substances are stored or in use or where hazardous activities are in progress. 5. If minors are permitted in laboratories, ensure that they are under the direct supervision of qualified adults at all times. Develop a policy regarding minors in the laboratory , and review and approve all activities of minors prior to their arrival. Make sure other laboratory personnel in the area are aware of the presence of minors .

37. Reducing Exposure to Chemicals Take care to avoid exposure by the principal routes: skin and eye contact, inhalation, and ingestion. The preferred methods for reducing chemical exposure, in order of preference, are as follows. 1. Substitution of less hazardous materials. 2. Engineering controls 3. Administrative controls 4. Personal protective equipment

38. Engineering Controls Engineering controls are measures that eliminate, isolate, or reduce exposure to chemical or physical hazards through the use of various devices. Examples include laboratory chemical hoods and other ventilation systems, shields, barricades. Engineering controls must always be the first and primary line of defense to protect personnel and property .

39. Housekeeping An orderly laboratory is a safe laboratory. By contrast, a disorderly laboratory can hinder or endanger emergency responders. Follow these housekeeping rules: 1. Regularly clean work areas, including floors, to reduce respiratory hazards. Properly label and neatly store all chemicals in order. Face labels outward for easy viewing. Containers themselves should be clean and free of dust. For containers and labels that have begun to degrade, replace, repackage, or dispose of them in the proper location . Return all equipment and laboratory chemicals to their designated storage locations.

40. Cont………. 5. Do not store chemical containers on the floor. 6. Do not use floors, stairways, and hallways as storage areas.