Chemical Safety In Schools Environmental Sciences Essay
Chemistry plays an important role in human civilization. It enables us to formulate substances important for disease treatment, fertilize plants and provide fuel for transportation ( ). For many years, chemistry has been considered the central science due to its significant connections and overlap with other sciences. If a scientific discipline involves matter, chances are that chemistry plays an important role. Therefore, we will always need people who have a good knowledge of chemistry. As expressed by Beach and Stone (1988) “chemistry education without laboratory is like painting without colors and canvas or learning how to ride a bike by reading its operating manual” (Tezcan and Bilgin, 2004). The study of chemistry in schools equips students with knowledge in the classroom and skills of conducting experiments in laboratories during practical sessions that are scheduled once a week for a period of two to three hours (MOH, 2001).
2.1.2 Hazards Chemical in the School Experiments
The teaching of chemistry at secondary school includes the use of hazardous chemical, which is essential for the understanding of chemistry fundamentals. Example of hazardous chemicals that are available at school chemistry laboratory are hydrochloric acid, sulfuric acid, acetic acid, natrium hydroxide, hydrogen sulfate, ammonium sulfate, hydrogen peroxide, ethanol, propanol and acetone (MOH, 2000). These chemicals are classified as hazardous chemicals to health under the Malaysia Occupational Safety and Health (Use and Standards of Exposure of Chemical Hazardous to Health) Regulations 2000. In view of their hazardous characteristics, the government through the Department of Occupational Safety and Health regulates labelling and packaging of these chemicals. A specific law pertaining to these hazardous chemicals, the Occupational Safety and Health (Classification, Packaging & Labelling of Hazardous Chemicals) Regulations 1997 (MDC, 2005), was established under the Occupational Safety and Health Act 1994 (Act 514) later revised based on the Global Harmonized System of Classification and Labelling of Chemicals to enforce the regulation. The chemicals are classified as hazardous based on their physicochemical characteristics and toxicity to human. Oxidizing and flammable chemicals have the potential to cause fire while corrosive and toxic chemicals have the potential to cause external and internal body injuries. For example, volatile organic compound such as acetone, ethanol and formaldehyde have been suggested to cause a nervous system disorder experienced by workers known as “solvent syndrome”, due to prolonged exposure to organic solvents (Dalton et al., 1997; John & Gary, 2001; Kiesswetter et al., 1994; Medinsky et al., 1995). Malaysian Occupational Safety & Health (Act 514) and Occupational Safety & Health Regulation 2000 (Use and Standard of Exposure to Chemicals Hazardous to Health) specify the permissible exposure level (PEL). The PEL is the maximum time-weighted average concentration of hazardous chemicals in the air of working area that workers can be exposed without the need to wear personal protective equipment and the PEL for acetone, ethanol and formaldehyde are 1187.0, 1880.0 and 0.4 mg/m3, respectively (MDC, 2005).
2.1.3 Safety Precautions
In view of the physical and health hazards of the chemicals, there is requires the implementation of safety precaution and hazard control to reduce the risk of exposure to the chemical hazards. Safety precaution differs based on the type of the chemical hazards. Safety precautions differ based on the type chemical hazards. General safety precaution is personal hygiene whereby the user as advice:
To wash hand
Wear lab coat
No eating and drinking
Wear covered shoes
Wear eye protection (goggles)
Example of additional safety precautions in
2.1.4 Responsibility of Chemistry Teachers
The teacher is a key figure in implementing the teaching of chemical science because, without a teacher, students cannot carry out the science practicum well. These students would have had no scientific competence, no skill in conducting experiments, and they would not be able to make observations and analyze experimental data (Senior High School Chemistry Practice in Pekanbaru Riau, 2012). Schools very much rely on chemistry teachers and laboratory staff (laboratory assistants and technicians) in managing the chemistry laboratory. Their tasks include the inventory, storage, repackaging, preparation of experiment reagent, conducting practical curriculum, cleaning of the apparatus and waste collection. Therefore, they play a big role in the practice and regulation of chemical safety in the school chemistry laboratory. Furthermore, they must also provide information and training to the students at every stage of experiment planning and be there to observe, supervise, instruct, and correct during the experimentation (School Chemistry Laboratory Safety Guide, 2006). Teachers and teacher-aides should lead by example – they should wear personal protective equipment, follow and enforce safety rules, procedures and practices, as well as demonstrated safe behavior and promote a culture of safety. They should be proactive in every aspect of laboratory safety and make, safety a priority. Figure 1 is a checklist for teachers that highlight essential information for working in a high school laboratory. This is a general safety checklist and should be periodically re-evaluated for updates (School Chemistry Laboratory safety Guide NIOSH, 2006).
Upkeep of Laboratory and Equipment
Recordkeeping
Safety and Emergency Procedures
Maintenance of Chemicals
2.1.5 Chemical Hazard Symbols (Pictograms)
In referring to the Global Harmonized System regulation, each package of chemical and the respective storage place should be clearly labelled with the relevant hazard symbol (pictogram) to communicate the related hazard, subsequently to reduce risk of chemical exposure of the incident. The hazards pictograms or symbols have been standard would be in hygiene______ and ______
Hazard and risk warning signs (label) of chemicals are something that anyone entering into laboratories should understand and be familiar. They are commonly assigned to each chemical in order to draw the attention of users and to classify chemicals according to their characteristics. The knowledge of potential hazards and risks of chemicals and understanding their labels would help to make correct choices and safe utilization and handling of chemicals. These procedures, ultimately, would help to avoid chemical-related accidents on individuals and the environment. There are different approaches to assign hazard-warning signs (labels) to chemicals in order to communicate to the user for their safe handling in laboratories and design safety measures to avoid preventable hazards on users. These labels (warning sign) consist of different colors and pictures and intended to provide information about properties of chemicals such as flammability, toxicity, explosive, corrosive, oxidizing, irritating and harmfulness. Understanding or becoming familiar with the labels of these properties would help to avoid unwanted but preventable hazards of laboratory chemicals. Therefore, for safety reasons, individuals working in chemistry laboratories and in other laboratories that involve the use of chemicals are supposed to be aware of the potential hazards of laboratory chemicals and become familiar with the warning sign of each chemical in use. Chemical storage areas can be the most dangerous places in most facilities. Placing the correct warning signs and labels around chemicals is essential to maintaining workplace safety. Hazard symbols are designed to warn about hazardous materials or locations. The use of hazard symbols is regulated by law and directed by standards organizations.
Table 1.2: Physical Hazards
Hazard
Symbol (Old)
Symbol
(New)
Description
Explosive
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Risk of Explosion by shock, friction, fire or other sources of ignition.
Handle substance very carefully
Do not smoke
Keep away from all sources of ignition
Oxidizing
http://www.hse.gov.uk/chip/images/ox-l.gif
May cause fire due to chemical reaction of Organic peroxides
Keep substance tightly lidded when not in use
Keep substance separate from other substances
Extremely Flammable
http://www.hse.gov.uk/chip/images/fire-l.gif
Highly Flammable
http://www.hse.gov.uk/chip/images/fire-l.gif
Risk of fire – Has a flashpoint of below 21oC
Keep away from all sources of ignition
Wear rubber soled shoes when using to avoid sparks from static electricity
Do not smoke
Keep substance tightly lidded & in a suitable metal cabinet when not in use
Flammable
http://www.hse.gov.uk/chip/images/fire-l.gif
Table 1.2: Health Hazards
Hazard
Symbol (Old)
Symbol
(New)
Description
Very Toxic
http://www.hse.gov.uk/chip/images/skull-l.gif
May cause irreversible health problems or even death if inhaled, ingested or if it enters the skin.
Wear suitable toxic mask, gloves, eye & face protection
DO NOT breathe vapours, dusts or mists
Avoid contact with skin & eyes
Toxic
http://www.hse.gov.uk/chip/images/skull-l.gif
Harmful
http://www.hse.gov.uk/chip/images/x-l.gif
Corrosive
http://www.hse.gov.uk/chip/images/corro-l.gif
Irritant
http://www.hse.gov.uk/chip/images/x-l.gif
Source: Globally Harmonized System of Classification and Labelling of chemicals, United Nations New York and Geneva, 2005.
2.1.6 Chemical Safety and Data Sheet
Chemical Safety Data Sheet (CSDS) also known as (SDS), (MSDS) or (PSDS) is an important component of product stewardship and workplace safety. The CSDS, prepared by a product manufactured or distributed by a supplier, contains more information about the chemical than its label.
A CSDS is a document that contains information on the potential health effects of exposure to chemicals, or other potentially dangerous substance, and on safe working procedures when handling a chemical product. It is an essential starting point for the development of a complete health and safety program. The document containing finding of the evaluations on the use, storage, handling and emergency procedures related to a specific chemical. The purpose is to communicate the hazards of the product, safe to use the product, possible consequences if the recommendations are not followed, actions to take if accidents occur, as well as symptoms of overexposure and steps to follow if such incidents occur.
In Malaysia, as specified in Classification, Packaging & Labelling Regulation 1997, chemical suppliers must supply MSDS as part of the requirement for a sale. The recent USECHH regulation 2000 also requires all chemical industry users to have each chemical’s MSDS on hand prior to the usage of the chemical in their workplace. Therefore, an MSDS is a very useful source of safety and health information that will help create a safer practice when dealing with chemicals. The information in the CSDS is divided into sections as below:
Product Identification
Provide general identification of the chemicals. Example: Synonyms, CAS No., Molecular Weight, Chemical Formula, Product Codes (if applicable)
Composition / Information on Ingredient
Provide the percentage or concentration of the chemical. Some may provide additional hazard information such as PEL (Permissible Exposure Limit), TLV (Threshold Limit Value) etc. Therefore, the seriousness of the chemicals can be referred.
Hazards Identification
Provide the degree of hazard with reference to:
Health rating
Flammability rating
Reactivity rating
Contact rating
Additional information may include the potential health effects and symptom through inhalation, ingestion, dermal contact, eye contact, chronic exposure & aggravation of pre-existing conditions (if applicable)
First Aid Measures
To provide first aid attention prior to the arrival of the physician when accident takes place. The piece of information provided may refer to the chemical accident due to:
Inhalation
Ingestion
Dermal Contact
Eye Contact
Fire Fighting Measures
Provide details on the Flash point, Auto Ignition Temperature, Flammability of the chemical product and Explosion capability information. Additional information may include of the proper methods of using fire extinguishing media (dry chemical, foam, water or carbon dioxide) and type of suitable fire fighting protective clothing used during a fire emergency.
Accidental Release Measures
Provide some essential guideline to deal with for instance how to deal with chemical spillage, ventilation provision, contain and recover liquid when spilled etc.
Handling & Storage
Provide detail to conduct, handling and storing at a safer way. These may include:
How to protect the chemical?
How to store the chemicals (environment factors consideration)?
Is it compatible with other chemicals when stored together?
How to use it at a safer way?
Exposure Controls/ Personal Protection
Provide details how to control the exposure of employees at the workplace when using such chemical, for example:
Ventilation system
PPE (Respirator, safety goggle, glove, SCBA, apron etc) for skin, eye and other bodily related protection
Physical / Chemical Properties
Provide detail of some of properties of chemical, for instance:
Appearance (clear, colorless, milky etc)
Odor (type of “smell” of product)
Solubility (Water soluble, slight solubility etc)
pH
Boiling point, melting point (OC or F)
Vapor density
Vapor pressure
Evaporation rate
Stability & Reactivity
Provide some details on:
Stability and reactivity of the chemical (e.g. during storage)
Type of hazardous decomposition products (e.g. release of certain gases such as CO2 when heated)
Compatibilities with other chemicals (for example acrylic acid is incompatible with strong oxidizing agents)
Toxicological Information
This section may refer to the toxicity of the chemical with reference to the LD 50 and LC 50. The lower the value of the LC the more hazardous will be the chemical
Ecological Information
Provide some detail on ecological impact of the chemical when it is used or discharged to the air, water or soil. Therefore, the user could take some precautious or probably engineering control when deal with this chemical
Disposal Considerations
Applied for the chemical that couldn’t be recycled, saved or recovered and is considered as hazardous waste. (Must comply with local requirements)
Transport Information
Provide some detail on the identification during transportation of chemical for both domestic and international purposes
Regulatory Information
Provide some details of the regulatory information from different relevant countries. Additional item would be the inclusive of Hazchem Code from Australia
Other Information
Provide certain information on for example,
NFPA rating in term of health, flammability and reactivity rating.
Label hazard warning. (E.g. DANGER! MAY BE FATAL IF SWALLOWED)
Label pre-cautious. (E.g. Do not breathe vapor or mist)
Label of first aid. (E.g. Do not induce vomiting, give large plenty of water)
Product use (if applicable)
An example of the CSDS is describe in Appendix.
Interactive Multimedia Courseware
An information technology innovation that emerged drastically leads to an improvement of its uses in teaching and learning, hence allowing multimedia software to be a popular teacher and nowadays (Mona Masood & Nor Azilah Ngah, 2003). Interactive multimedia roused in 1990 where innovative educators started to think of the implication of new media if being adapted to teaching and learning environment. This technological development leads on changes in every life sector consists of education, economy, social and others (G. Torrisi-Steele, 2005).
Definition of multimedia
The definitions of Interactive Multimedia described in published articles seem to vary between authors. Below are some of the definitions:
Fenrich (1997) described multimedia as the exciting combination of computer hardware and software that allows users to integrate video, animation, audio, graphics, and test resources to develop effective presentations on an affordable desktop computer.
Phillips (1997) characterized multimedia by the presence of text, pictures, sound, animation and video, some or all of which organized into a coherent program.
Multimedia is a multi-sensory interactive user experience, which is defined as a combination of at least one continuous (i.e. sound and video) and one discrete (i.e. text and images) medium (Neo and Neo, 2004).
“Interactive Multimedia”, as described by the encyclopedia Britannica Online, is defined as any computer-delivered electronic system that allows the user to control, combines, and manipulate different types of media, such as text, sound, video, computer graphics, and animation.
Types of Multimedia
The challenge of multimedia to humanity is thinking through the variety of multimedia artifacts and asking about the clusters of work that can be aggregated into categories such as Web hypermedia, Computer games, Digital Art and Multimedia Encyclopedia. Web hypermedia refers to a work created to explore the possibilities for hypertext and multimedia in education. Most commercially successful multimedia works are computer games. Games like Myst introduced consumers of all ages to the effective use of images, animations, and environmental sound to create a fictional world characterized by navigation and puzzle solving. Digital art has been using multimedia to create interactive installations that are controlled by computers and use multiple media. These playful works are exhibited in galleries and museums as works of art that bring multimedia into the traditions of art exhibition. A common form of educational and reference multimedia is the multimedia encyclopedia like the Encyclopedia Britannica Online and Microsoft’s Encarta (on CD-ROM).
Components of Multimedia Courseware
According to Fenrich (1997), media categories incorporated into an instructional multimedia package are as follows:
The text is the most common medium of presenting information. It is also used to communicate a concept or an idea. It should effectively complement the other media. Factors that influence the textual communication are typeface, font and style, kerning, antialiasing, animation, special effects, special characters and hypertext. While dealing with text in a multimedia, it is very important to note that, it is not the only means of communication. In multimedia, text is most often used for titles, headlines, menus, navigation and content. Overcrowding of text on a single page should be avoided.
Audio is another vital media in a multimedia presentation. Audio is available in different file formats and choosing the appropriate file format is important to maximize its performance on the multimedia. Sound editors play an important role in converting file formats and enhancing the quality of sound. In most cases, sound files are imported and edited for a multimedia application.
Video in multimedia is an extremely useful communication tool for presentations. It illustrates ideas and concepts better than static two-dimensional pictures besides capturing real world events. Video files occupy enormous space and there are two recommendations:
Use very short video clips (not exceeding a minute or two)
Use highly compressed video files such as MPEG. One could also transform AVI files to MPEG files.
Graphics are the most commonly used element of multimedia. The richness of multimedia and effective communication is achieved through graphic presentations. The attributes of color, texture, pattern and animation enrich a multimedia presentation.
A very popular and a chief element of multimedia is animation. The key concepts of computer animation are key frames and tweening. Animation is a simulation of movement created by displaying a series of pictures or frames. Animation is strictly a visual illusion. It builds dynamism, energy and motion onto inanimate objects. It also adds the dimension of time to graphics. Computer animation is relevant to multimedia as all the presentations are developed on the computer.
Multimedia Interactivity
Barker (1994) defines interactivity in learning as a necessary and fundamental mechanism for knowledge acquisition and the development of both cognitive and physical skills. Scientific research shows that the process of remembering in the human brain is faster when people receive much emphasis in various forms for a short period. The concept of interactivity in multimedia helps the human brain to improve the process of learning (Application of multimedia Technology in University Teaching-4). Examination of 75 learning studies (Bosco, 1986; Fletcher, 1990) found that people learn faster and have better attitudes toward learning the material when they learn in an interactive instructional environment (, 2003). Thus, the interactivity is seen an important character for an effective multimedia courseware.
Damarin (1982) identified a series of interactive options, which include watching, finding, doing, using, constructing, and creating. While Ambron and Hooper (1988) described interactivity as a state in which users are able to browse, annotate, link and elaborate within a rich, nonlinear database. Hence, interactivity is seen to boost motivation in learning. Motivation is another important factor that should be considered when designing multimedia courseware. Ideally, users should experience an intrinsic desire to engage in the presentation; being interested in completing the task for their own sake rather than because of any value attached to their completion. For meaningful learning to occur, it is important to design for intrinsic motivation on the part of its users (Biggs and Moore, 1993).
Intervention Tool for Chemical Safety Education
Multimedia enables a way for learners to experience simultaneous graphic, video and audio, rather than in a sequential manner. Moreover, multimedia can provide an enhanced or augmented learning experience at low cost per unit. The power of multimedia can be unleashed to provide long-term benefits to all. Multimedia enrich the learning experience through exploration and discovery. The process of learning can become more goals oriented, participatory, flexible in aspects of time and space, and tailored to individual learning styles. Multimedia allows learning to become fun and friendly, without fear of inadequacies or failure (, 2003). It uses natural information-processing abilities that we already possess. Our eyes and ears, in conjunction with our brain, form a formidable system for transforming meaningless data into information. Another advantage of multimedia courseware over the text-based variety is that the multimedia is visually more simulating. Even when the courseware includes only a few images of little pedagogical value, it at least provides relief from the screen of text and stimulates the eye. (, 2003).
2.3 Learning Aided by Instructional Design using Interactive Multimedia Courseware
Instructional Design is a discipline of study and has evolved over the last forty years as a science. It is a young field inspired from areas of communication, psychology and media to form its own theory. Various authors have defined instructional design in their own way. McArdle (1991) defines Instructional Design simply as using a systematic process to understand a human performance problem, figuring out what to do about it and then doing something about it. Richey (1986) defines Instructional Design as the science of creating detailed specifications for the development, evaluation and maintenance situations that facilitate learning. Briggs (1977) defines Instructional Design as the entire process of analysis of learning needs and goals and the development of a delivery system to meet the needs.
Learning is primarily the process through which we become the person we are, and it takes place through a variety of media, strategies, and processes, of which interactive multimedia are just one of them. Using these media and technologies, we internalize information and knowledge available in the external world to construct our own experiences (, 2004). Individuals learn, retain, and transfer information better through (Interactive Multimedia in Education and Training, 2004):
Table 1.1: Principles that influence the effectiveness of multimedia as described by
No.
Principle
Details
1
Multimedia principle
When the instructional environment involves words and pictures alone
2
Modality principle
When the instructional environment involves auditory narration and animation rather than on-screen text and animation
3
Redundancy principle
When the instructional environment involves narration and animation rather than on-screen text, narration, and animation
4
Coherence principle
When the instructional environment is free of extraneous words, pictures and sounds
5
Signalling principle
When the instructional environment involves cueing, or signals, that guide an individual’s attention and processing during a multimedia presentation
6
Contiguity principle
Where words or narration and pictures or narration are presented simultaneously in time and space
7
Segmentation principle
Where individuals experience concurrent narration and animation in short, user-controlled segments, rather than as a long continuous presentation
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