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Metrication Best Practices

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Metrication Process | Metric-only Operations | Hybrid or Dual Operations

Organizations know their business model and are positioned to make the best decision for their operations. For organizations systematically adopting the International System of Units (SI) within their business systems, these practices have been identified to ease transitions and reduce costs. Consider these practices when beginning the transition to metric operations. Select those that fit the organization and situation.

Metrication Process

  • Achieve management support to conduct an efficient and economical metrication process.
  • Centralize coordination and enable local management control. Establish a metric working group, task force, or advisory committee that is responsible for developing and implementing a transition plan, monitoring process success, and communicating progress status with management and staff. Planning will address the impacts on areas such as people, design, production, inventory, purchases, and sales.
  • Plan the process to minimize costs and maximize benefits.
  • Investigate metric practices and activities both within the industry and with related industry sectors, customers, and competitors.
  • Conduct a measurement system analysis to identify where measurement units are used across all business processes and systems. Analyze the flow of each product through the production process and evaluate measurement related tasks. Identifying measurements across operations reduces the likelihood of unit mix-ups. Determining all measurement applications will help ensure required financial and personnel resources are available to sustain a successful transition.
  • Use a checklist to assist staff organization, evaluation, and implementation of tasks to help ensure important processes are not skipped.
  • Develop or adopt an SI best practice guide that includes tips on writing with the SI.
  • Assess the current management system, quality control procedures, safety systems, software, job instructions, documentary standards, design specifications, blueprints, and other guidance documents to implement appropriate updates.
  • Evaluate tools, equipment, and software systems. Modern measurement-sensitive tools are designed to read in both SI and non-SI units. Identify necessary adjustments, modifications, and updates. Recalibrate measurement instruments as needed. Validate and verify software systems before implementation.
  • Convert systems quickly. Reducing the time spent using dual measurement units decreases the chance of significant errors.
  • Analyze the availability of metric components and materials from current suppliers and vendors. Communicate the organization’s metrication plan to suppliers. Discuss updated specifications and deadlines when metric designs will be required. Offer insights from lessons learned.  Learn more about developing manufacturing supply chain risk management strategies.
  • Evaluate new domestic and foreign opportunities. Market new capabilities to furnish metric products and services.
  • Incorporate metric products and specifications into all customer communication channels, including product specifications, instructions, manuals, promotional literature, websites, social media, and other resources.
  • Any plan to convert measurement systems must consider legacy measurements, such as those used in systems or equipment with a long service life. Failing to account for legacy measures could result in inefficiencies or errors.

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Metric-only Operations

  • Plan new products using metric best practices. Significant metrication occurs when emerging technologies or new product lines enter the U.S. marketplace, developed from the bottom up using metric measurement practices. New technology is a driver of metric adoption. Many manufacturers implement metric transition when new projects are brought online because this is when SI measurements are integrated most efficiently (i.e., as a normal cost of doing business rather than an added expense).
  • Train employees only on the metric measures required to perform their task; simplified training reduces the costs related to conversion.
  • Minimize the quantity of unit magnitudes utilized. Consolidating units reduces opportunities for error. For example, some applications may only use millimeters to clearly represent length measurements in whole numbers, avoiding decimal values.
  • Evaluate personnel SI knowledge. Affirming employee measurement system proficiency reduces the likelihood of errors. Collaborate with the internal training program to eliminate knowledge and skill gaps with professional development and training. The level of training will vary across positions. Consider the specific needs of marketing, administration, design, production, quality, inspection, and other technical personnel.

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Hybrid or Dual Operations

Simultaneously working in multiple measurement systems frequently results in mistakes, mishaps, inefficiencies, and other unintended consequences. For organizations and individuals working in hybrid or dual measurement environments, these practices have been identified to help prevent costly errors:

  • Conduct a measurement system analysis to identify where measurement units are used across all business processes and systems. Identify measurements across operations to analyze risks and implement strategies to mitigate unit mix-ups.
  • Prepare to bear the expenses associated with managing separate inventory and storage for separate non-SI (U.S. customary) and SI designed supplies, component stock and products.  
  • Evaluate personnel non-SI and SI knowledge. Affirming employee measurement system proficiency and eliminating knowledge gaps with professional development and training help minimize the likelihood of errors.
  • Establish a system of marking that clearly distinguishes SI from non-SI tools, instruments, supplies, and materials.
  • Display a complete quantity declaration that includes both a numeric value and measurement unit. Explicitly stating measurement units reduces the opportunity for misinterpretation and related errors. Supplement knowledge gaps with training and educational resources.
  • Ensure accurate unit conversion ratios are used if unit conversion is required. Examining the conversion ratios reduces the chance of unit conversion errors. Establish a numerical rounding policy. Unit conversion ratios and rounding guidance are available in NIST Special Publication (SP) 811 Appendix B and other publications.
  • Validate and verify software used for unit conversion calculations. When using software to make critical unit conversions, particularly those in trade or commerce, determine if the program uses the appropriate conversion factors and that it appropriately rounds for the application to ensure the final quantity is accurate. Conduct an analysis before placing new or updated systems into service, placing special attention on measurement-sensitive calculations.

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Explore Metrication Resources

Disclaimer: Any mention of commercial products within NIST web pages is for information only; it does not imply recommendation or endorsement by NIST.

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Created July 13, 2022, Updated September 26, 2022