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Sources of Safety Information
Manufacturers and employers throughout the world provide a vast amount of safety information to workers, both to encourage safe behaviour and to discourage unsafe behaviour. These sources of safety information include, among others, regulations, codes and standards, industry practices, training courses, Material Safety Data Sheets (MSDSs), written procedures, safety signs, product labels and instruction manuals. Information provided by each of these sources varies in its behavioural objectives, intended audience, content, level of detail, format and mode of presentation. Each source may also design its information so as to be relevant to the different stages of task performance within a potential accident sequence.
Four Stages of the Accident Sequence
The behavioural objectives of particular sources of safety information correspond or “map” naturally to the four different stages of the accident sequence (table 1).
Table 1. Objectives and example sources of safety information mapped to the accident sequence
Task stage in accident sequence |
||||
Prior to task |
Routine task performance |
Abnormal task conditions |
Accident conditions |
|
Objectives |
Educate and persuade worker of the nature and level of risk, precautions, remedial measures and emergency procedures. |
Instruct or remind worker to follow safe procedures or take precautions. |
Alert worker of abnormal conditions. Specify needed actions. |
Indicate locations of safety and first aid equipment, exits and emergency procedures. Specify remedial and emergency procedures. |
Example |
Training manuals, videos or programmes, hazard communication programmes, material safety data sheets, safety propaganda, safety feedback |
Instruction manuals, job performance aids, checklists, written procedures, warning signs and labels |
Warning signals: visual, auditory, or olfactory. Temporary tags, signs, barriers or lock-outs |
Safety information signs, labels, and markings, material safety data sheets |
First stage. At the first stage in the accident sequence, sources of information provided prior to the task, such as safety training materials, hazard communication programmes and various forms of safety programme materials (including safety posters and campaigns) are used to educate workers about risks and persuade them to behave safely. Methods of education and persuasion (behaviour modification) attempt not only to reduce errors by improving worker knowledge and skills but also to reduce intentional violations of safety rules by changing unsafe attitudes. Inexperienced workers are often the target audience at this stage, and therefore the safety information is much more detailed in content than at the other stages. It must be emphasized that a well-trained and motivated workforce is a prerequisite for safety information to be effective at the three following stages of the accident sequence.
Second stage. At the second stage in the accident sequence, sources such as written procedures, checklists, instructions, warning signs and product labels can provide critical safety information during routine task performance. This information usually consists of brief statements which either instruct less skilled workers or remind skilled workers to take necessary precautions. Following this approach can help prevent workers from omitting either precautions or other critical steps in a task. Statements providing such information are often embedded at the appropriate stage within step-by-step instructions describing how to perform a task. Warning signs at appropriate locations can play a similar role: for example, a warning sign located at the entrance to a workplace might state that safety hard hats must be worn inside.
Third stage. At the third stage in the accident sequence, highly conspicuous and easily perceived sources of safety information alert workers of abnormal or unusually hazardous conditions. Examples include warning signals, safety markings, tags, signs, barriers or lock-outs. Warning signals can be visual (flashing lights, movements, etc.), auditory (buzzers, horns, tones, etc.), olfactory (odours), tactile (vibrations) or kinaesthetic. Certain warning signals are inherent to products when they are in hazardous states (e.g., the odour released upon opening a container of acetone). Others are designed into machinery or work environments (e.g., the back-up signal on a fork-lift truck). Safety markings refer to methods of non-verbally identifying or highlighting potentially hazardous elements of the environment (e.g., by painting step edges yellow or emergency stops red). Safety tags, barriers, signs or lock-outs are placed at points of hazard and are often used to prevent workers from entering areas or activating equipment during maintenance, repair or other abnormal conditions.
Fourth stage. At the fourth stage in the accident sequence, the focus is on expediting worker performance of emergency procedures at the time an accident is occurring, or on the performance of remedial measures shortly after the accident. Safety information signs and markings conspicuously indicate facts critical to adequate performance of emergency procedures (e.g., the locations of exits, fire extinguishers, first aid stations, emergency showers, eyewash stations or emergency releases). Product safety labels and MSDSs may specify remedial and emergency procedures to be followed.
However, if safety information is to be effective at any stage in the accident sequence, it must first be noticed and understood, and if the information has been previously learned, it must also be remembered. Then the worker must both decide to comply with the provided message and be physically able to do so. Successfully attaining each of these steps for effectiveness can be difficult; however, guidelines describing how to design safety information are of some assistance.
Design Guidelines and Requirements
Standards-making organizations, regulatory agencies and the courts through their decisions have traditionally both instituted guidelines and imposed requirements regarding when and how safety information is to be provided. More recently, there has been a trend towards developing guidelines based on scientific research concerning the factors which influence the effectiveness of safety information.
Legal requirements
In most industrialized countries, government regulations require that certain forms of safety information be provided to workers. For example, in the United States, the Environmental Protection Agency (EPA) has developed several labelling requirements for toxic chemicals. The Department of Transportation (DOT) makes specific provisions regarding the labelling of hazardous materials in transport. The Occupational Safety and Health Administration (OSHA) has promulgated a hazard communication standard that applies to workplaces where toxic or hazardous materials are in use, which requires training, container labelling, MSDSs and other forms of warnings.
In the United States, the failure to warn also can be grounds for litigation holding manufacturers, employers and others liable for injuries incurred by workers. In establishing liability, the Theory of Negligence takes into consideration whether the failure to provide adequate warning is judged to be unreasonable conduct based on (1) the foreseeability of the danger by the manufacturer, (2) the reasonableness of the assumption that a user would realize the danger and (3) the degree of care that the manufacturer took to inform the user of the danger. The Theory of Strict Liability requires only that the failure to warn caused the injury or loss.
Voluntary standards
A large set of existing standards provide voluntary recommendations regarding the use and design of safety information. These standards have been developed by multilateral groups and agencies, such as the United Nations, the European Economic Community (EEC’s EURONORM), the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC); and by national groups, such as the American National Standards Institute (ANSI), the British Standards Institute, the Canadian Standards Association, the German Institute for Normalization (DIN) and the Japanese Industrial Standards Committee.
Among consensus standards, those developed by ANSI in the United States are of special significance. Since the mid-1980s, five new ANSI standards focusing on safety signs and labels have been developed and one significant standard has been revised. The new standards are: (1) ANSI Z535.1, Safety Color Code, (2) ANSI Z535.2, Environmental and Facility Safety Signs, (3) ANSI Z535.3, Criteria for Safety Symbols, (4) ANSI Z535.4, Product Safety Signs and Labels, and (5) ANSI Z535.5, Accident Prevention Tags. The recently revised standard is ANSI Z129.1–1988, Hazardous Industrial Chemicals—Precautionary Labeling. Furthermore, ANSI has published the Guide for Developing Product Information.
Design specifications
Design specifications can be found in consensus and governmental safety standards specifying how to design the following:
Table 2. Summary of recommendations within selected warning systems
System |
Signal words |
Colour coding |
Typography |
Symbols |
Arrangement |
ANSI Z129.1 |
Danger |
Not specified |
Not specified |
Skull-and-crossbones as supplement to words. |
Label arrangement not specified; examples given |
ANSI Z535.2 |
Danger |
Red |
Sans serif, upper case, |
Symbols and pictographs |
Defines signal word, word message, symbol panels in 1 to 3 panel designs. 4 shapes for special use. Can use ANSI Z535.4 for uniformity. |
ANSI Z535.4 |
Danger |
Red |
Sans serif, upper case, |
Symbols and pictographs |
Defines signal word, message, pictorial panels in order of general to specific. Can use ANSI Z535.2 for uniformity. Use ANSI Z129.1 for chemical hazards. |
NEMA Guidelines: |
Danger |
Red |
Not specified |
Electric shock symbol |
Defines signal word, hazard, consequences, instructions, symbol. Does not specify order. |
SAE J115 Safety Signs |
Danger |
Red |
Sans serif typeface, upper |
Layout to accommodate |
Defines 3 areas: signal word panel, pictorial panel, message panel. Arrange in order of general to specific. |
ISO Standard: ISO |
None. 3 kinds of labels: |
Red |
Message panel is added |
Symbols and pictographs |
Pictograph or symbol is placed inside appropriate shape with message panel below if necessary |
OSHA 1910.145 Specification for Accident Prevention |
Danger |
Red |
Readable at 5 feet or as |
Biological hazard symbol. Major message can be supplied by pictograph |
Signal word and major message (tags only) |
OSHA 1910.1200 |
Per applicable |
In English |
Only as Material Safety Data Sheet |
||
Westinghouse |
Danger |
Red |
Helvetica bold and regular |
Symbols and pictographs |
Recommends 5 components: signal word, symbol/pictograph, hazard, result of ignoring warning, avoiding hazard |
Source: Adapted from Lehto and Miller 1986; Lehto and Clark 1990.
Certain standards may also specify the content and wording of warning signs or labels in some detail. For example, ANSI Z129.1 specifies that chemical warning labels must include (1) identification of the chemical product or its hazardous component(s), (2) a signal word, (3) a statement of hazard(s), (4) precautionary measures, (5) instructions in case of contact or exposure, (6) antidotes, (7) notes to physicians, (8) instructions in case of fire and spill or leak and (9) instructions for container handling and storage. This standard also specifies a general format for chemical labels that incorporate these items. The standard also provides extensive and specific recommended wordings for particular messages.
Cognitive guidelines
Design specifications, such as those discussed above, can be useful to developers of safety information. However, many products and situations are not directly addressed by standards or regulations. Certain design specifications may not be scientifically proven, and, in extreme cases, conforming with standards and regulations may actually reduce the effectiveness of safety information. To ensure effectiveness, developers of safety information consequently may need to go beyond safety standards. Recognizing this issue, the International Ergonomics Association (IEA) and International Foundation for Industrial Ergonomics and Safety Research (IFIESR) recently supported an effort to develop guidelines for warning signs and labels (Lehto 1992) which reflect published and unpublished studies on effectiveness and have implications regarding the design of nearly all forms of safety information. Six of these guidelines, presented in slightly modified form, are as follows.
Satisfying these guidelines requires consideration of a substantial number of detailed issues as addressed in the next section.
Developing Safety Information
The development of safety information meant to accompany products, such as safety warnings, labels and instructions, often requires extensive investigations and development activities involving considerable resources and time. Ideally, such activities (1) coordinate the development of product information with design of the product itself, (2) analyse product features which affect user expectations and behaviours, (3) identify the hazards associated with use and likely misuse of the product, (4) research user perceptions and expectations regarding product function and hazard characteristics and (5) evaluate product information using methods and criteria consistent with the goals of each component of product information. Activities accomplishing these objectives can be grouped into several levels. While in-house product designers are able to accomplish many of the tasks designated, some of these tasks involve the application of methodologies most familiar to professionals with backgrounds in human factors engineering, safety engineering, document design and the communication sciences. Tasks falling within these levels are summarized as follows and are shown in figure 1 :
Figure 1.A model for designing and evaluating product information
Level 0: Product design status
Level 0 is both the starting point for initiating a product information project, and the point at which feedback regarding design alternatives will be received and new iterations at the basic model level will be forwarded. At the initiation of a product information project, the researcher begins with a particular design. The design can be in the concept or prototype stage or as currently being sold and used. A major reason for designating a Level 0 is the recognition that the development of product information must be managed. Such projects require formal budgets, resources, planning, and accountability. The largest benefits to be gained from a systematic product information design are achieved when the product is in the pre-production concept or prototype state. However, applying the methodology to existing products and product information is quite appropriate and extremely valuable.
Level 1: Product type investigations
At least seven tasks should be performed at this stage: (1) document characteristics of the existing product (e.g., parts, operation, assembly and packaging), (2) investigate the design features and accompanying information for similar or competitive products, (3) collect data on accidents for both this product and similar or competitive products, (4) identify human factors and safety research addressing this type of product, (5) identify applicable standards and regulations, (6) analyse government and commercial media attention to this type of product (including recall information) and (7) research the litigation history for this and similar products.
Level 2: Product use and user group research
At least seven tasks should be performed at this stage: (1) determine appropriate methods for use of product (including assembly, installation, use and maintenance), (2) identify existing and potential product user groups, (3) research consumer use, misuse, and knowledge of product or similar products, (4) research user perceptions of product hazards, (5) identify hazards associated with intended use(s) and foreseeable misuse(s) of product, (6) analyse cognitive and behavioural demands during product use and (7) identify likely user errors, their consequences and potential remedies.
After completing the analyses in Levels 1 and 2, product design changes should be considered before proceeding further. In the traditional safety engineering sense, this could be called “engineering the hazard out of the product”. Some modifications may be for the health of the consumer, and some for the benefit of the company as it attempts to produce a marketing success.
Level 3: Information design criteria and prototypes
In Level 3 at least nine tasks are performed: (1) determine from the standards and requirements applying to the particular product which if any of those requirements impose design or performance criteria on this part of the information design, (2) determine those types of tasks for which information is to be provided to users (e.g., operation, assembly, maintenance and disposal), (3) for each type of task information, determine messages to be conveyed to user, (4) determine the mode of communication appropriate for each message (e.g., text, symbols, signals or product features), (5) determine temporal and spatial location of individual messages, (6) develop desired features of information based on messages, modes and placements developed in previous steps, (7) develop prototypes of individual components of product information system (e.g., manuals, labels, warnings, tags, advertisements, packaging and signs), (8) verify that there is consistency across the various types of information (e.g., manuals, advertisements, tags and packaging) and (9) verify that products with other brand names or similar existing products from the same company have consistent information.
After having proceeded through Levels 1, 2 and 3, the researcher will have developed the format and content of information expected to be appropriate. At this point, the researcher may want to provide initial recommendations regarding the redesign of any existing product information before moving on to Level 4.
Level 4: Evaluation and revision
In Level 4 at least six tasks are performed: (1) define evaluation parameters for each prototype component of the product information system, (2) develop an evaluation plan for each prototype component of the product information system, (3) select representative users, installers and so on, to participate in evaluation, (4) execute the evaluation plan, (5) modify product information prototypes and/or the design of the product based on the results obtained during evaluation (several iterations are likely to be necessary) and (6) specify the final text and artwork layout.
Level 5: Publication
Level 5, the actual publication of the information, is reviewed, approved and accomplished as specified. The purpose at this level is to confirm that specifications for designs, including designated logical groupings of material, location and quality of illustrations, and special communication features have been precisely followed, and have not been unintentionally modified by the printer. While the publication activity is usually not under the control of the person developing the information designs, we have found it necessary to verify that such designs are precisely followed, the reason being that printers have been known to take great liberties in manipulating design layout.
Level 6: Post-sale evaluations
The last level of the model deals with the post-sale evaluations, a final check to ensure that the information is indeed fulfilling the goals it was designed to achieve. The information designer as well as the manufacturer gains an opportunity for valuable and educational feedback from this process. Examples of post-sale evaluations include (1) feedback from customer satisfaction programmes, (2) potential summarization of data from warranty fulfilments and warranty response cards, (3) gathering of information from accident investigations involving the same or similar products, (4) monitoring of consensus standards and regulatory activities and (5) monitoring of safety recalls and media attention to similar products.
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