FMVSS 218 refers to the Federal Motor Vehicle Safety Standard number 218. To avoid duplication while preserving the meaning, you could phrase it as follows:
1. Federal Safety Standard for Motor Vehicles 218.
2. Motor Vehicle Safety Regulation 218 issued by the federal government.
3. U.S. Federal Regulation 218 concerning vehicle safety.
4. National standard 218 for motor vehicle safety.
5. Vehicle safety guideline number 218 established by federal authorities.
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