Standards and the Design Engineer

Many design engineers have a “love/hate” relationship with standards. Most engineers realize that standards contain a wealth of helpful information and that designing to certain standards is wise and often mandatory. However, there is a simple dichotomy between the words “design” and “standard”—how can something “standard” contribute to something as creative as “design?” Also, with the plethora of standards available—corporate, industry, national, regional, international, government—finding all of the right, most useful standards can be a daunting task that many engineers would rather not pursue.

Successful design engineers know how to find the right standards and use them as the foundation for design that is innovative, socially responsible, and cost-effective. This white paper explores some of the ways design engineers use standards to the benefit of their organizations, society, and themselves.

Basically, the design engineer’s job is to produce a detailed product design from a product concept. The engineer’s ability to foresee potential downstream problems is key, since design flaws can be very costly, or even dangerous. The typical cost of design changes at each stage of product development is shown in the following table.

Standards help engineers save time and money by providing accepted descriptions of product criteria, processes, tests, and procedures that can be used as a basis for new design drawings, specifications and/or models. To eliminate costly rework, standards should be considered in the early stages of the design process.

Design based on accepted standards helps organizations:

• Ensure quality, reliability, and safety
• Gain wider market acceptance
• Strengthen economies in purchasing
• Comply with government or customer requirements
• Ensure interchangeability of parts and system interoperability
• Improve buyer/seller and intra-company communication
• Avoid the proliferation of internal specifications and drawings

Since each engineering problem is different, there is not a definitive process that satisfies every design problem. However, generally accepted methodology usually includes the following steps. At each step, the impact of standards should be taken into account.

• Design brief
• Product design specification
• Concept design and evaluation
• Detail design

Design Brief

The design brief simply states the design problem and defines the project direction. You may want to mention the need to conform to certain standards. For instance, the item may need to meet American National Standards Institute (ANSI) standards if it is to be sold in the U.S., British Standards Institution (BSI) standards if sold in the United Kingdom, and ISO (International Organization for Standardization) standards if it is to be marketed worldwide.

Product Design Specification

This step details the design problem and is possibly the most important step of the design process. The designer should constantly refer back to this document to ensure that designs are appropriate.

At this stage, ALL applicable standards and requirements should be identified. Most products must comply with a number of standards. Each product component usually has to comply with at least one standard. For instance, if a product incorporates an electric motor, the motor will have to comply with the relevant electric motor standards. It is important to thoroughly research the problem, work with the customer, and analyze the marketplace and competing products.

Depending on the product to be designed, the product design specification may address any or all of the topics in the following table. Each topic should cite critical standards, and a special “standards” section should list all of the standards applicable to the product.

When designing a product it is important to consider the activities downstream of the design stage, such as manufacture, sales, and transportation. These activities usually use accepted standards for testing of quality, consistency, customer acceptance, and ongoing compliance. Identifying these testing standards early in the design process can eliminate downstream problems.

Concept Design and Evaluation

Using the product design specification, designers create a number of viable concept designs. A concept design is a usually an outline of key components and their general arrangement. The details are filled in later. The concept design might be a sketch. The degree of detail will vary depending on the product being designed. Annotation helps identify key points so that ideas can be communicated with others in the company. Compliance with important standards should be noted.

The concept designs are evaluated and the most suitable one is chosen for detail development. The product design specification should be used as the basis of this decision. Ideally, a multifunctional team should perform this task so that the concept designs are evaluated from a number of perspectives.

Detail Design

In this stage of the process, the chosen concept design is detailed, with all the dimensions and specifications necessary to manufacture the product. It is usually best to reference applicable standards in the detailed documentation rather than include the entire text. Referencing reduces the size of the documentation and ensures that your document is not obsolete if the standard is modified.

It may be necessary to produce prototypes to test ideas at this stage. By using standard test techniques, the product can be shown, with confidence, to meet the standards required for quality, safety, and compliance.

Knowing when and how to use standards is critical to product design. The number and type of standards used depends on many factors, including regulations, customer requirements, supplier requirements, internal company processes, and market acceptance. Every effort should be made to identify ALL applicable standards and requirements upfront to eliminate downstream problems and costly rework.