scope:

The purpose of this manual is to provide guidelines for the development and implementation of a successful odorization program for the operator of a gas transmission or distribution pipeline system. The manual is not intended to provide standards, specific procedures, station designs or monitoring procedures for individual company operations. The manual does not recommend or endorse specific products, instruments or equipment. It provides information to consider for compliance with the odorization regulations. The subjects covered include federal regulations and guidance material for odorization and coordination of odorization activities with other compliance programs, such as public awareness, operator qualifications, operating manuals, environmental protection and safety. Other topics include odorant chemical and physical properties, odorization system design and operations, testing of odor and odorant levels, and updated information on odor fade and masking, pipeline conditioning (pickling) and a high-level summary of employee training.

In this manual, unless otherwise stated, the term "gas" is used to mean combustible gases. It includes all combustible gases entering transmission and distribution pipelines from sources, such as conventional natural gas, coal seam gas, shale gas, renewable natural gas (biomethane), storage gas, propane-air, refinery gas, vaporized liquefied natural gas (LNG) and compressed natural gas (CNG) entering into a pipeline system. The manual does not address odorization of combustible gases delivered in tanks, such as liquid petroleum gas (LPG).

The information presented herein is not intended to cover all the details and aspects of odorization or to provide detailed operating procedures. It should provide the reader with an understanding of basic concepts of odorization and an overview of regulatory obligations, as well as guidelines that can help the reader design odorization systems and develop practices and procedures to safely and effectively odorize natural gas.