Kaiyi Manual for CNG Vehicle Maintenance (EN)

Acknowledgments This guide provides a review of all aspects of indoor compressed natural gas vehicle maintenance facility protection, including the initial assessment of the facility, code compliance requirements, and specific design criteria. The authors would like to acknowledge Gladstein, Neandross & Associates in providing considerable information and photos during the development of this handbook. Authors Kay Kelly and Margo Melendez, National Renewable Energy Laboratory Co-Authors John Gonzales and Lauren Lynch, National Renewable Energy Laboratory Bob Coale and Jarrod Kohout, Gladstein, Neandross & Associates Work Sponsor The U.S.

Department of Energy Vehicle Technologies Office, Clean Cities program, and Dennis A. Smith and Mark S. Smith Reviewers Steve Saltzgiver, Mercury Associates, Inc. Ted Barnes, Gas Technology Institute Rob Adams, Marathon Technical Services, LLC Andrew Klock and Susan Bershad, National Fire Protection Association Stephe Yborra, Yborra & Associates, LLC Disclaimer This report was prepared as an account of work sponsored by an agency of the United States government.

Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof.

The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Every effort has been made to ensure that this manual is accurate, complete, and comprehensive at the time of publication. It is intended to be used as a guide and resource document. The authors strongly encourage all parties with an interest in establishing compressed natural gas vehicle maintenance facilities to engage professional support to ensure code compliance and optimal systems operation. This document is not intended for use as a “how to” guide for individuals or organizations performing facility modifications.

COMPRESSED NATURAL GAS VEHICLE MAINTENANCE FACILITY MODIFICATION HANDBOOK II

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Glossary Air Changes per Hour (ACH): A measurement of the number of volumetric air exchanges within a structure caused by natural or mechanical ventilation. International Fire Code (IFC): A guidance document commonly used with, or in lieu of, NFPA 30A that covers the design of vehicle maintenance facilities and protection systems. Authority Having Jurisdiction (AHJ): Person(s) or agency responsible for reviewing, approving, and permitting proposed modifications, and issuing construction and occupancy permits. For the purposes of this document an AHJ is an agency. International Mechanical Code (IMC):

A guidance document that establishes regulations for the design and operation of mechanical systems based on prescriptive and performance-based provisions commonly used with, or in lieu of, NFPA 30A. Class I, Division 1 Electrical Hazard Zone: A zone that is expected to contain hazardous concentrations of gas or vapor in the event of a spill or leak which, therefore, must be provided with ignition source protection. Lower Flammability Limit (LFL): The minimum concentra­ tion of a combustible gas that will support combustion; sometimes referred to as the lower explosive limit (LEL). This is generally accepted to be 5% natural gas in air by volume at atmospheric conditions.

Class I, Division 2 Electrical Hazard Zone: A zone which may contain hazardous concentrations of gas or vapor and, therefore, must be protected. For compressed natural gas vehicle maintenance facilities, Class I, Division 2 represents conditions in which methane releases could occur but are not expected. Major Repair Garage: A maintenance facility in which major repairs are performed, such as engine overhauls, vehicle chassis and body repairs, and similar work, that require emptying the vehicle’s fuel tank. Any work that involves service to a vehicle’s fuel system also falls into this category. Compressed Natural Gas (CNG):

Natural gas that consists primarily of methane and small amounts of ethane, propane, and heavier hydrocarbons and has been compressed and stored in high-pressure vessels at pressures up to 5,000 pounds per square inch (psi). Make-up Air: Fresh air that replaces air that is exhausted from a structure. Methane (CH 4 ): The primary component of natural gas. Creditable Release: A release of natural gas within a repair garage that results in a plume of sufficient concentration that it exceeds the lower flammability limit. Minor Repair Garage:

A maintenance facility in which minor repairs are performed, such as lubrication, engine tune-ups, replacement of parts and tires, fluid changes, and similar maintenance work, that does not require emptying a vehicle’s fuel tank. Any work that involves service to a vehicle’s fuel system is not permitted in a Minor Repair Garage. Design-Build (DB): A type of contract whereby the selected contractor is responsible for the complete design of the facility, securing permits, procurement, construction, commissioning, startup, and often maintenance activities. Design-Bid-Build (DBB):

A type of contract whereby one consultant is responsible for preparing the facility design and permitting documents while a building contractor is responsible for pulling permits, procuring equipment and materials, construction, commissioning, startup, and sometimes maintenance activities. National Fire Protection Association (NFPA): NFPA is a global, nonprofit organization devoted to eliminating death, injury, and property and economic loss due to fire, electrical hazards, and related threats.

NFPA’s codes and standards are designed to minimize the risk and effects of fire by estab­ lishing criteria for building, processing, design, service, and installation in the United States, as well as many other countries. NFPA 30A is the basic document used in conjunc­ tion with maintenance facilities. Portions of NFPA 88A may also apply. Hot Work: A type of maintenance work involving the use of oxyacetylene torches and/or electric arc welders. This could also include the use of grinders or other spark- producing tools. Ignition Source: A spark, flame, electricity, static electricity, or hot surface capable of igniting a fuel that is within its combustible range. Natural Gas:

Natural gas used as a vehicle fuel is composed of 90%–95% methane and other longer-chain simple hydrocarbons. When used in the gaseous state, natural gas SEPTEMBER 2017 III

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is compressed to pressures up to 5,000 psi and is commonly known as compressed natural gas (CNG). Natural gas is odor­ ized with mercaptan to yield the familiar “rotten egg” smell. Natural Gas Vehicle: A motor vehicle with a combustion engine fueled by natural gas. Paths of Migration: The flow paths by which natural gas travels as it dissipates throughout a structure. Pressure Relief Device (PRD): A valve activated by high temperature or pressure used to eliminate overpressure in a vehicle fuel tank or system. A temperature-activated valve is designed to open at a given temperature (for example in the event of a fire) and remain open.

Once the device is activated, the valve remains permanently open and cannot be reset to the closed position. A pressure-activated valve is designed to open at a given pressure and will remain open until the overpressure is released. This type of valve is resettable and will reseal when the lower prescribed pressure is realized. Pressure Release Valve (PRV): A type of valve used to control or limit the pressure in a system or vessel. A PRV is usually resettable and when activated by high pressure will open to release the overpressure until a lower prescribed pressure is realized, then reseal.

PRVs are usually found on stationary tanks and equipment and can also be used for vehicle pressure regulators. PRVs are also known as safety relief valves (SRVs). Upper Flammability Limit (UFL): The maximum concen­ tration of a combustible gas that will ignite; sometimes referred to as the upper explosive limit (UEL). This is generally accepted to be 15% natural gas in air by volume at atmospheric conditions. COMPRESSED NATURAL GAS VEHICLE MAINTENANCE FACILITY MODIFICATION HANDBOOK IV

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Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Facility Assessment and Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . 6 Paths of Migration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Space Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15 Electrical Wiring, Lighting, and Appliance Considerations . . . . . . . . . . . . . . . 16 Gas Detection, Alarm, and Control Systems . . . . . . . . . . . . . . . . . . . . . . . . . 19 Other Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Vehicle Fuel System Defueling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Engine Exhaust Extractors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Isolation of Non-Work Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Automatic Shut-Off of Building Gas Supply . . . . . . . . . . . . . . . . . . . . . . . . . .

25 Associated Bays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Project Costs and Schedules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Facility Modification Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Facility Modification Timelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Appendix A. Specific Properties of Common Vehicle Fuels . . . . . . . . . . . . . . . . . 31 Appendix B. Preliminary Maintenance Facility Assessment . . . . . . .

. . . . . . . . . 32 Appendix C. Minor/Major Maintenance Facility Assessment . . . . . . . . . . . . . . . . 34 SEPTEMBER 2017 1

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