1.1 本规范涵盖甲基异丁基酮（99.0 % 等级）。 1.2 有关具体的危险信息和指导，请参阅本规范中所列材料的供应商材料安全数据表。 1.3 以下内容适用于本标准中的所有规定限值；为了确定是否符合本标准，应根据修约实践方法，将观察值或计算值修约到用于表示规范极限的最后一个右手数字中的“最接近的单位” E29年 . 1.4 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。

1.1 This specification covers methyl isobutyl ketone (99.0 % grade). 1.2 For specific hazard information and guidance, see the supplier's Material Safety Data Sheet for materials listed in this specification. 1.3 The following applies to all specified limits in this standard; for purposes of determining conformance with this standard, an observed value or a calculated value shall be rounded off “to the nearest unit” in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29 . 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.