OVERVIEW OF PROPANE DISTRIBUTION SYSTEMS FOR HVAC AND PLUMBING PROFESSIONALS
SAMPLE COURSE
COURSE OBJECTIVES
ICOURSE OBJECTIVES
YOUR COURSE SAMPLE OVERVIEW OF PROPANE DISTRIBUTION SYSTEMS FOR HVAC AND PLUMBING PROFESSIONALS
Thank you for downloading this sample of Overview of Propane Distribution Systems for HVAC and Plumbing Professionals. This includes the following sections of the course:
• Overview.
• Module 1 – Introduction.
• Module 2 – Propane Basics.
For modules 3-8, as well as resources including quizzes, videos, student materials, and more, download the full course here, or visit PropaneProfessional.com.
DISCLAIMER
IIDISCLAIMER
NOTICE AND DISCLAIMER CONCERNING LIABILITY
The Propane Education & Research Council is a non-profit 501(c)6 trade organization authorized by the Propane Education and Research Act of 1996, Public Law 104-284. PERC was created “to enhance consumer and employee safety and training, to provide for research and development of clean and efficient propane utilization equipment, and to inform and educate the public about safety and other issues associated with the use of propane.”
PERC is governed by a 21 member Board of Directors appointed by the National Propane Gas Association and the Gas Processors Association. PERC program beneficiaries include propane retail marketers, producers, transporters and agricultural cooperatives, as well as representatives of allied service and supply industries (industry members).
The recommendations, standards, or recommended practices, as reflected in this document, were developed by independent consultants retained by PERC. While PERC administers the process of obtaining the information, it does not independently test or verify the accuracy of the information or methods used to collect the data that supports the conclusions or recommendations reflected in this document. PERC, NPGA, GPA and the industry members disclaim any liability for any personal injury, property damage, business losses or other damages of any nature whatsoever, whether special, indirect, consequential or compensatory, directly or indirectly resulting from the publication, use, or reliance on this document, or any information, apparatus, method, process, or similar item disclosed in this document. This disclaimer of liability shall apply even if such loss or damage results, in whole or in part, from any acts or omissions of or by any negligence on the part of PERC, NPGA, GPA or industry members or any persons who contributed to the development of the information contained in this document.
PERC, NPGA, GPA, and industry members make no warranty or guaranty as to the accuracy or completeness of any information published in this document.
Text and code references found in this document are based on the 2015 edition of NFPA 54: National Fuel Gas Code and the 2017 edition of NFPA 58: Liquefied Petroleum Gas Code. The procedures and information in this document are intended to implement the standards set forth in the documents referenced with capabilities of the personnel and equipment available. It does not create new standards or criteria for compliance. The order of steps in any procedure may or may not be of importance. This material is not sold nor is it a product of any consulting or engineering activity.
Users of this document should consult the law of their individual jurisdictions for codes, standards, and legal requirements applicable to them. This document is not intended nor should it be construed to (1) set forth policies or procedures which are the general custom or practice in the HVAC and plumbing industries or to prevent the user from using different methods to implement applicable codes, standards, or legal requirements.
By disseminating or publishing this document, PERC is not undertaking to render any professional or other service to or on behalf of any person or entity. PERC, NPGA, GPA and the industry members are not undertaking to perform any duty owed by any person or entity to any third party. Anyone reading or using this document should rely on his or her own judgment or, as appropriate, should seek the advice of a competent professional in determining the exercise of reasonable care in any and all circumstances.
Propane Education & Research Council 1140 Connecticut Ave., NW, Suite 1075
Washington, DC 20036
propanecouncil.org • propane.com
©2018 Propane Education & Research Council. All Rights Reserved. No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission.
TABLE OF CONTENTS
III TABLE OF CONTENTS
TABLE OF CONTENTS – SAMPLEOVERVIEW ICourse Objectives I
Disclaimer II
MODULE 1: COURSE INTRODUCTION 1Welcome 1
Lesson 1. Course Overview and Objectives 2
Safety Mission 2
Who Should Take This Course? 3
Course Purpose 4
Course Objectives 5
Course Format 5
Course Resources and References: Codes 6
MODULE 2: PROPANE BASICS 7Introduction 7
Lesson 1. Sources and Characteristics of LP-Gas 8
Introduction 8
Sources of Liquefied Petroleum Gas 8
Important Characteristics of LP-Gas 9
Check for Understanding: Sources and Characteristics 10
Lesson 2. Physical Properties of Propane 11
Introduction 11
Specific Gravity 11
Specific Gravity of Liquids 12
Specific Gravity of Vapors 13
Check for Understanding: Physical Properties of Propane 14
Pressure and Temperature Effects on Propane 15
Boiling Point of Propane 16
Temperature and Pressure Balance 17
Propane Boiling Action: Valve Opened 18
Propane Boiling Action: Valve Closed 19
Effects of Pressure and Temperature: Product Expansion 20
Effects of Pressure and Temperature: Additional Information 21
Check for Understanding: Physical Properties of Propane 22
Lesson 3. Propane Safety Information 23
Introduction 23
If You Smell Gas or Suspect a Gas Leak 23
Gas Service Interruptions and Related Factors 24
Service Interruptions: Policies, Procedures, and Regulations 25
Customer Safety 26
Importance of Good Documentation 27
Check for Understanding: Propane Safety Information 28
Lesson 4. Uncontrolled Propane Release 29
Introduction 29
What is an Uncontrolled Release of Propane? 30
Who is an Emergency Responder? 31
What to Do In the Event of an Emergency 32
Evacuate the Affected Area 33
Be Aware of Your Surroundings 34
Call for Help 35
When Help Arrives 36
Post Event Actions 37
Module 2 Summary 38
MODULE 3: THE VAPOR DISTRIBUTION SYSTEM 43Introduction 43
Lesson 1. Propane Containers 45
Introduction 45
Vaporization and Container Sizing 46
Lesson 2. Regulators 47
Introduction 47
Purpose of a Regulator 47
Regulator Sizing and Selection 48
Check for Understanding: Regulators 49
Lesson 3. Gas Piping 51
Introduction 51
Sizing Gas Piping 52
Identifying Problems with Pipe Sizing 54
Check for Understanding: Gas Piping 55
Module 3 Summary 56
TABLE OF CONTENTS
VTABLE OF CONTENTS
TABLE OF CONTENTS – SAMPLEMODULE 4: GAS PIPING, PROPANE CONTAINER, AND REGULATOR LOCATION REQUIREMENTS 57Introduction 57
Lesson 1. Gas Piping Stub Out Location 59
Introduction 59
Check for Understanding: Gas Piping Stub Out Location 62
Lesson 2. Propane Container Location 63
Introduction 63
Location of Containers 64
Check for Understanding: Propane Container Location 67
Lesson 3. Regulator Location 69
Introduction 69
Location of Regulators 70
Check for Understanding: Regulator Location 71
Module 4 Summary 72
MODULE 5: APPLIANCE INSTALLATION REQUIREMENTS 73Introduction 73
Lesson 1. Venting System 75
Introduction 75
Importance of Proper Venting 76
Vented Appliances Categories 77
Temperature and Condensation 79
Proper Venting Materials 79
Providing Proper Clearances 80
Check for Understanding: Venting System 81
Lesson 2. Combustion, Dilution, and Ventilation Air 83
Introduction 83
Combustion and Ventilation Air 84
Dilution and Makeup Air 84
Check for Understanding: Combustion, Dilution, and Ventilation Air 86
Lesson 3. Appliance Locations 87
Introduction 87
Clearances to Combustibles 88
Appliance Location Code Requirements 89
Lesson 4. Appliance Conversion 91
Introduction 91
Check the Name Plate 92
Dedicated Appliances 93
Convertible Appliances 94
High Altitude Combustion 95
High Altitude Operation 96
Tagging Converted Appliances 97
Check for Understanding: Appliance Conversion 98
Module 5 Summary 99
MODULE 6: INTERIOR GAS PIPING INSTALLATION REQUIREMENTS 101Introduction 101
Lesson 1. Piping Materials 103
Introduction 103
Piping Material 104
Plastic Pipe and Anodeless Riser 105
Lesson 2. Piping, Fittings, and Component Installation 107
Introduction 107
Piping Supports 108
Sediment Traps and Shutoff Valves 109
Drip Legs 110
Appliance Connectors 111
Appliance Connector Requirements 112
Other Design Requirements 113
Check for Understanding: Piping, Fittings, and Component Installation 114
Lesson 3. Bonding Requirements 115
Introduction 115
Electrical Bonding and Grounding 115
Check for Understanding: Bonding Requirements 116
Module 6 Summary 117
VTABLE OF CONTENTS
TABLE OF CONTENTS
TABLE OF CONTENTS – SAMPLEMODULE 7: VAPOR DISTRIBUTION SYSTEM TESTS AND CHECKS 119Introduction 119
Lesson 1. Pressure Test 121
Introduction 121
Test Per NFPA 58 122
Pressure Test Per NFPA 54 123
Test Pressure 124
Pressure Test Device 125
Pressure Test Duration 125
Additional Requirements 126
Check for Understanding: Pressure Test 127
Lesson 2. Leak Check 129
Introduction 129
Performing a Leak Check 130
Appliances with 100% Safety Shutoff Valves 131
Appliances Without 100% Safety Shutoff Valves 132
Leak Check Instruments 133
Leak Test 134
Check for Understanding: Leak Check 135
Lesson 3. Flow and Lock-Up Tests 137
Introduction 137
Purpose of Tests 138
Flow and Lock-Up 139
Regulators 140
Flow Test Using a Manometer 141
Flow Test Procedure 142
Flow Test at Second-Stage or Line Regulator 143
Flow Test at 2-PSI or First-Stage-Regulator 144
Lock-Up Test for Second or Integral 2-State Regulator 145
Lock-Up Test for First-Stage or 2-PSI Regulator 147
Documenting System Tests and Checks 148
Check for Understanding: Flow and Lock-Up Tests 149
Module 7 Summary 150
MODULE 8: PLACING APPLIANCES INTO OPERATION 151Introduction 151
Lesson 1. Purging a Gas Piping System 153
Introduction 153
Purging 153
Check for Understanding: Purging a Gas Piping System 154
Lesson 2. Appliance Startup 155
Introduction 155
Requirements for Placing Appliances Into Initial Operation 156
Code Requirements 157
Lighting Appliance Pilots 158
Verifying Manifold Pressure 159
Proper Burner Operation 160
Inadequate Air Supply 161
Excessive Air Supply 162
Safety Devices 163
Types of Safety Devices 163
Spillage Test 164
Check for Understanding: Appliance Startup 165
Module 8 Summary 166
CHECK YOUR WORK 167
RESOURCES 175PERC Safety Brochure for Customers 176
MODULE 1
1MODULE 1
MODULE 1 COURSE INTRODUCTION
WELCOME
Welcome to Overview of Propane Distribution Systems for HVAC and Plumbing Professionals. The primary purpose of this course is to provide HVAC and plumbing professionals an overview of how to design, install, test, and operate propane appliances and vapor distribution systems in a safe manner.
This course has been developed in partnership with the Propane Education & Research Council and other industry experts to promote the safe and efficient use of propane as a preferred energy resource.
The propane industry is committed to providing the highest level of safety and service to its customers, employees, and the entire propane community.
Safety is at the heart of our commitment, and high-quality training is an essential tool for ensuring your safety and continuing success.
MODULE 1
LESSON 1: COURSE OVERVIEW AND OBJECTIVES
SAFETY MISSION
Safety is an industry-wide responsibility that extends to everyone who handles propane. The more you know about working with propane the more you help reduce the risk of accidents.
Each of us in the propane, HVAC, and plumbing industries can contribute to a shared mission by doing all we can to increase public confidence in the safety and value of propane.
SAFETY GOALS
To fully achieve this safety mission, the propane industry has established five critical goals:
• Prevent accidents and incidents.
• Improve safety awareness.
• Increase consumer confidence.
• Strengthen employees’ skills and knowledge.
• Improve regulatory compliance.
2MODULE 1
3
MODULE 1
MODULE 1
WHO SHOULD TAKE THIS COURSE?
Since safety and reliability are everyone’s business, employees throughout the HVAC and plumbing industries will find this training useful, and perhaps even lifesaving. However, this course has been specifically designed to train:
• Plumbers.
• HVAC technicians.
MODULE 1
4MODULE 1
COURSE PURPOSE
The purpose of this course is to provide participants with the knowledge necessary to verify that gas appliances meet code and safe operational requirements. Participants will also be able to recognize and identify the impact that propane vapor distribution system installations and appliances may have on stakeholders.
This course is not intended to provide detailed, comprehensive information about the topics, procedures, and regulations addressed in this training. Rather, it is designed as an awareness-level, overview course for HVAC technicians and plumbers. For a complete understanding of the topics covered in this course, you should refer to the Certified Employee Training Program (CETP) courses listed below, as well as other in-depth industry training programs.
Additional CETP Courses:
• CETP 1.0: Basic Principles and Practices of Propane
• CETP 4.1: Designing and Installing Exterior Vapor Distribution Systems
• CETP 4.2: Placing Vapor Distribution Systems and Appliances into Operation
• CETP 4.3: Installing Appliances and Interior Vapor Distribution Systems
5
MODULE 1
MODULE 1
COURSE OBJECTIVES
After completing this course, you will be able to:
• Identify the sources, characteristics, and physical properties of propane.
• Follow general propane safety information.
• Identify the main components of a vapor distribution system and how they work together to supply adequate gas pressure to appliances.
• Identify various code requirements for container and regulator installation.
• Explain the effects that a gas piping stub out or side-wall vent termination may have on the propane container or regulator location.
• Verify that propane appliances are installed in a safe and code compliant manner.
• Determine interior gas piping requirements.
• Explain the different vapor distribution system tests and checks, including pressure test, leak check, and regulator and system flow and lockup test.
• Identify gas system and appliance startup requirements.
COURSE FORMAT
Overview of Propane Distribution Systems for HVAC and Plumbing Professionals is organized into eight modules, each with one or more lessons. Each module includes:
• Up-to-date information, procedures, and regulations; effective as of the date of publication.
• Questions to check for understanding.
MODULE 1
6MODULE 1
COURSE RESOURCES AND REFERENCES: CODES
Many agencies of the federal government play major roles in developing regulations, codes, and standards to ensure the safe handling and use of propane. Here are some common references used in this course:
• The National Fire Protection Association (NFPA).
- NFPA 54, National Fuel Gas Code: This publication provides standards for the installation of fuel gas piping systems, appliances, equipment, and related accessories.
- NFPA 58, Liquefied Petroleum Gas Code: This publication provides standards for the storage, handling, and transportation of propane.
- NFPA 70, National Electric Code: This publication is the benchmark for safe electrical design, installation, and inspection to protect people and property from electrical hazards.
• 29 CFR, Code of Federal Regulations: Occupational Health and Safety Standards. This publication sets standards to promote and enforce employee safety in the workplace.
Always check with your supervisor to determine all of the safety codes that apply to your job responsibilities. As a general rule, it is important that you follow the manufacturer’s instructions when installing and using propane products.
MODULE 2
7MODULE 2
MODULE 2 PROPANE BASICS
INTRODUCTION
This module will provide you with a basic understanding of where propane comes from, its characteristics, and the physical properties of propane. The concept of specific gravity, and effects of temperature and pressure on propane will also be presented. In this module, you will also learn about customer safety and what to do if you smell gas or suspect a gas leak. Next, this module will discuss policies, procedures, and regulations that pertain to a gas service interruption. Finally, this module identifies steps to take in an uncontrolled propane release.
OBJECTIVES
After completing this module, you will be able to:
• Identify the sources of Liquefied Petroleum gases (LP-gases).
• Explain the concept of specific gravity of propane liquid and vapor.
• Identify the effects of pressure and temperature on propane.
• Identify what to do if you smell gas or suspect a gas leak.
• Explain what may be required when the gas service is interrupted.
• Identify what to do if there is an uncontrolled release of propane.
• Identify how to encourage people to safely evacuate the scene of an emergency.
• Identify information that must be provided to 911 or other emergency response operators in the event of an emergency.
MODULE 2
8MODULE 2
LESSON 1: SOURCES AND CHARACTERISTICS OF LP-GAS
INTRODUCTION
As an HVAC or plumbing professional, it is important to understand where propane comes from and some of its basic characteristics.
SOURCES OF LIQUEFIED PETROLEUM GAS
The main sources of Liquefied Petroleum Gas (LP-gas) are:
• The refining of crude oil.
• The processing of natural gas from wet gas wells.
These two sources are very different. But once refined, there’s little difference between LP-gases processed from these sources.
For additional information on the sources and characteristics of LP-gas, you should refer to CETP 1.0: Basic Principles and Practices of Propane.
PROCESSING AND REFINEMENT
NATURAL GASBUTANE
PROPANE
GASOLINEHEATING OIL
9
MODULE 2
MODULE 2
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IMPORTANT CHARACTERISTICS OF LP-GAS
• Tasteless, colorless, and odorless.
• Will burn when mixed with the proper amount of air.
• Can be solid, liquid, or vapor under varying conditions.
• Stored and transported as a liquid under pressure and readily vaporizes into gas when the pressure in the container drops.
• Liquid propane expands when heated; if stored in a container, the expansion increases the volume of the liquid and the pressure of the vapor and liquid inside a container.
• Propane readily vaporizes and expands when released to the atmosphere.
• Not toxic, but presents an asphyxiation hazard if inhaled in a vapor state because LP-gases displace oxygen.
Will burn when mixed with air Vaporizes into gases when container pressure drops
MODULE 2
10MODULE 2
CHECK FOR UNDERSTANDING: SOURCES AND CHARACTERISTICS OF LP-GAS
Let’s take a moment to check how well you understand the information presented in this lesson by selecting the question’s appropriate response. Check your work on page 167.
Select all that apply.
LP-gas:
a. Is colorless.
b. Is odorless.
c. Is stored and transported as vapor.
d. Will burn with the correct amount of air.
MODULE 2
11MODULE 2
LESSON 2: PHYSICAL PROPERTIES OF PROPANE
INTRODUCTION
In this lesson, you will learn about the concept of specific gravity to help you understand and compare the weights of propane liquid and vapor. You will also learn how pressure and temperature affect the way propane behaves.
SPECIFIC GRAVITY
One of the most common ways to calculate and compare the weights of liquids and vapors is to use a value called specific gravity. Understanding the weight of propane and how it compares with the weights of other liquids will help you know where to look for gases if they leak. It is important to understand specific gravity when trying to find the source of a leak or when working in an area where a leak has occurred.
12MODULE 2
MODULE 2
SPECIFIC GRAVITY OF LIQUIDS
The specific gravity of a vapor is the comparison of the weight of a given volume of a gas at a certain temperature with the same volume of air at the same temperature.
You calculate the specific gravity of a liquid by comparing it to water.
Here are some examples:
• If the specific gravity of a liquid at 60° F is 2.0, then a given volume of that liquid at 60° F is twice as heavy as the same volume of water at 60° F.
• If the specific gravity of a liquid at 60° F is 1.0, then a given volume of that liquid at 60° F weighs the same as a volume of water at 60° F.
• If the specific gravity of a liquid at 60° F is 0.5, then a given volume of that liquid at 60° F weighs half as much as a volume of water at 60° F.
Commercial propane liquid has an average specific gravity of 0.504 at 60° F. This means that propane liquid weighs a little more than half the weight of water at 60° F.
SPECIFIC GRAVITY OF VAPOR AT 600 F
VAPOR A
VAPOR B
VAPOR C
NATURAL GAS
PROPANE
0 0.5 1.0 1.5 2.0
AIR
SPECIFIC GRAVITY
1.50
SPECIFIC GRAVITY OF LIQUID AT 600 F
SPECIFIC GRAVITIES
SPECIFIC GRAVITIES
0 0.5 1.0 1.5 2.0
LIQUID A
LIQUID B
LIQUID C
PROPANE
WATER
SPECIFIC GRAVITY
0.504
MODULE 2
13MODULE 2
SPECIFIC GRAVITY OF VAPORS
The specific gravity of a vapor is the comparison of the weight of a given volume of a gas at a certain temperature with the same volume of air at the same temperature.
You calculate the specific gravity of a vapor by comparing it to air.
Here are some examples:
• If the specific gravity of a vapor at 60° F is 2.0, then a given volume of that vapor at 60° F weighs twice as much as the same volume of air at 60°F.
• If the specific gravity of a vapor at 60° F is 1.0, then a given volume of that vapor at 60° F weighs the same as a volume of air at 60°F.
• If the specific gravity of a vapor at 60° F is .5, then a given volume of that vapor at 60° F weighs half as much as the same volume of air at 60°F.
Commercial propane vapor has an average specific gravity of 1.50 at 60° F. This means that propane vapor weighs 1½ times the weight of air at 60° F.
Natural gas has a specific gravity of approximately 0.60. This means that natural gas is lighter than air (air being 1.0).
SPECIFIC GRAVITY OF VAPOR AT 600 F
VAPOR A
VAPOR B
VAPOR C
NATURAL GAS
PROPANE
0 0.5 1.0 1.5 2.0
AIR
SPECIFIC GRAVITY
1.50
SPECIFIC GRAVITY OF LIQUID AT 600 F
SPECIFIC GRAVITIES
SPECIFIC GRAVITIES
0 0.5 1.0 1.5 2.0
LIQUID A
LIQUID B
LIQUID C
PROPANE
WATER
SPECIFIC GRAVITY
0.504
14MODULE 2
MODULE 2
CHECK FOR UNDERSTANDING: PHYSICAL PROPERTIES OF PROPANE
Let’s take a moment to check how well you understand the information presented in this lesson by selecting the question’s appropriate response. Check your work on page 167.
The specific gravity of propane vapor is 1.50 at 60 degrees F and considered heavier than air and natural gas.
a. True.
b. False.
MODULE 2
15MODULE 2
PRESSURE AND TEMPERATURE EFFECTS ON PROPANE
Propane’s volume, pressure, and physical state (liquid or vapor) depend on how it is stored and the temperature of the surrounding environment.
The following three areas relate to the effects of pressure and temperature on propane:
• The effect of heat on liquids.
• Liquids and boiling points.
• Storing liquids above their atmospheric boiling points in a closed container.
16MODULE 2
MODULE 2
250˚
212˚
-44˚
60˚
100˚
250˚
212˚
-44˚
60˚
100˚
WATER PROPANE
BOILING POINT OF PROPANE
Like water, propane has a boiling point at which it changes from liquid to vapor. However, the boiling point of propane is so low, -44° F, that it will boil at normal temperatures most anywhere on earth. Therefore, you usually don’t need to apply an extra heat source to propane to make it boil. The heat in the air around us is more than enough.
But remember, if propane were kept at a temperature below its normal boiling point, -44° F, it would remain a liquid and could be stored in an open container.
MODULE 2
17MODULE 2
TEMPERATURE AND PRESSURE BALANCE
Propane is affected by heat and pressure in much the same way as water. Let’s take a look at that now.
The figure below shows propane liquid in a cylinder at a temperature of 60° F. At atmospheric pressure, the boiling point of propane is -44° F. At any temperature below that, a pool of propane will remain in liquid form, because its vapor pressure is less than atmospheric. At temperatures above -44° F, the vapor pressure of propane is greater than atmospheric pressure, therefore the liquid will vaporize.
In this case, when the propane liquid was pumped into the cylinder it began to boil and pressurize the vapor space of the cylinder. Once the pressure reached 102 psig, the pressure in the container and the vapor pressure of propane at 60° F were equal, and the boiling stopped.
Outside temperature also affects the vapor pressure inside the container.
Propane liquid in a cylinder at a temperature of 60° F
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250˚
212˚
-44˚
60˚
100˚
18MODULE 2
MODULE 2
PROPANE BOILING ACTION: VALVE OPENED
If the valve on a cylinder (or appliance) is opened, propane vapor will flow to the burner, and the demand for gas vapor will immediately cause a slight drop in pressure inside the cylinder.
This upsets the balance and will cause the propane to begin boiling off vapor to replace the vapor going to the burner. As long as the demand for vapor remains, the propane will continue to boil, supplying fuel to the burner.
If the valve on an appliance is opened more, then the demand for propane vapor is increased and the boiling rate will also increase. This same action will occur in a customer’s gas system, where the tank or cylinder containing liquid propane boils off gas vapor to provide fuel to appliances.
Next, we’ll see what happens when the valve is closed.
As long as the demand for vapor remains, the propane will continue to boil,
supplying fuel to the burner.
If the valve on an appliance is opened more, then the demand for propane
vapor is increased and the boiling rate will also increase.
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250˚
212˚
-44˚
60˚
100˚
PSI
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250˚
212˚
-44˚
60˚
100˚
MODULE 2
19MODULE 2
PROPANE BOILING ACTION: VALVE CLOSED
When the valve on the appliance is closed, the propane will stop flowing and return to its balance point. The boiling will slow down as the pressure in the vapor space increases to that balance point. The boiling will eventually stop as the balance is reached.
Except for their boiling points, propane is a lot like water.
The boiling will slow down as the pressure in the vapor space increases to that
balance point.
The boiling will eventually stop as the balance is reached.
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250˚
212˚
-44˚
60˚
100˚
PSI
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250˚
212˚
-44˚
60˚
100˚
20MODULE 2
MODULE 2
EFFECTS OF PRESSURE AND TEMPERATURE: PRODUCT EXPANSION
There are a few more important points to understand about the effects of pressure and temperature on propane:
• First, a propane container absorbs heat directly from the surrounding air. Hot days, cool nights, rain, and snow are just a few of the many factors that can affect the temperature of the propane liquid, which will cause changes in vapor pressure. It’s not uncommon for a container’s pressure to change. Propane liquid can increase more than 50 pounds of pressure or more in the course of a day, without an appliance operating. Propane liquid, like water, will expand when heat is added to it.
Containers are generally filled to about 80% of their capacity to account for effects of pressure and temperature.
This leaves space above the liquid for the propane to expand freely as temperatures change without danger of the container becoming over pressurized.
• Second, propane liquid expands in volume nearly 17 times greater than water even when they are exposed to the same increase in temperature. A propane container that is filled beyond the fixed maximum liquid level gauge may be at risk for an unintended propane release.
Containers are generally filled to about 80% of their capacity to account for effects of pressure and temperature.
A propane container that is filled beyond the fixed maximum liquid level gauge may be at risk for an unintended
propane release.
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80%
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MODULE 2
21MODULE 2
EFFECTS OF PRESSURE AND TEMPERATURE: ADDITIONAL INFORMATION
Every propane container is equipped with at least one pressure relief valve. This is necessary because of the change in liquid volume, as well as high storage pressures. If the pressure inside the container becomes too high, then the relief valve discharges vapor and reduces the pressure to a safe level. This ensures that the vapor pressure never reaches the maximum pressure the container is designed to handle, which could cause it to rupture.
Remember, a small volume of liquid boils off into a large volume of propane vapor. For example, one cubic foot of propane liquid will boil off into approximately 270 cubic feet of vapor. As a result, a leak in any propane container, large or small, can easily lead to a flammable mixture of propane and air.
It’s important for HVAC and plumbing professionals to have a better understanding of what takes place inside a propane container. If you encounter low gas pressure readings at an appliance or at the outlet of a gas regulator, the problem could be:
• Inadequate vapor pressure at the storage tank.
• The size of the gas piping.
• The regulator.
Each of these should be checked to rule out the problem. Additional information will be provided in later modules.
=1 270
1 CUBIC FT OF PROPANE LIQUID 270 CUBIC FT OF PROPANE VAPOR
NOTE: PICTURE IS NOT TO SCALE.
WARNING: Propane containers should always be stored upright and outside because of the effect that heat can have on the propane. Too much heat may cause the pressure relief valve to open and release propane into the atmosphere which may cause a potentially hazardous condition.
22MODULE 2
MODULE 2
CHECK FOR UNDERSTANDING: PHYSICAL PROPERTIES OF PROPANE
Let’s take a moment to check how well you understand the information presented in this lesson by selecting the question’s appropriate response. Check your work on page 167.
When propane vapor is withdrawn from a propane container, the vapor pressure will inside the container causing the liquid propane to begin to boil?
a. increase.
b. stay the same.
c. decrease.
d. none of the above.
MODULE 2
23MODULE 2
LESSON 3: PROPANE SAFETY INFORMATION
INTRODUCTION
This lesson will inform you about what steps to take if you smell gas or suspect a leak. You will also learn what the code requires when you restore service.
IF YOU SMELL GAS OR SUSPECT A GAS LEAK
If you smell gas or suspect a gas leak:
• NO FLAMES OR SPARKS! Immediately put out all smoking materials and other open flames. Do not operate lights, appliances, telephones, or cell phones. Flames or sparks from these sources can trigger an explosion or a fire.
• LEAVE THE AREA IMMEDIATELY! Get everyone out of the home or building or area where you suspect gas is leaking.
• SHUT OFF THE GAS. Turn off the main gas supply valve on the propane tank if it is safe to do so. To close the valve, turn it to the right (clockwise).
• REPORT THE LEAK. From a neighbor’s home or other nearby building away from the gas leak, call the propane retailer right away. If you can’t reach the propane retailer, call 911 or the local fire department.
• DO NOT RETURN TO THE BUILDING OR AREA. Until the propane retailer determines that it is safe to do so.
• GET YOUR SYSTEM CHECKED. Before you attempt to use any of the propane appliances, appropriate personnel must check the entire system to ensure that it is leak-free.
24MODULE 2
MODULE 2
GAS SERVICE INTERRUPTIONS AND RELATED FACTORS
Any time a gas distribution system loses gas pressure, a service interruption occurs. Without adequate gas pressure, appliance pilot lights could go out and if the safety device doesn’t function properly then a potentially unsafe condition may exist. Therefore, it is very important that all gas service interruptions be handled properly.
If you interrupt the gas service and cause a loss of pressure to the piping system, you will need to conduct a leak check according to your company policy. If you need assistance with doing so or with restoring the gas service, contact the propane supplier for assistance.
MODULE 2
SERVICE INTERRUPTIONS: POLICIES, PROCEDURES, AND REGULATIONS
There are several resources to support an investigation and response to a gas service interruption.
NFPA 54
Provisions for handling interruption of gas service as prescribed in the 2015 edition of NFPA 54, National Fuel Gas Code, include:
• Interruption of Service — When the gas supply is to be turned off, it shall be the duty of the qualified agency to notify all affected users.
Where two or more users are served from the same supply system, precautions shall be exercised to ensure that service only to the proper user is turned off.
• Leak Check — Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the piping system shall be checked for leakage.
Where leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made.
STATE AND LOCAL
In addition to following your company’s policies and procedures (along with those in NFPA 54), be aware of any other state and local guidelines that you’ll also need to follow.
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NOTE: Always follow your company’s procedures when responding to service calls.
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MODULE 2
CUSTOMER SAFETY
Safety brochures and decals can communicate specific warnings about propane and actions that your customer can take, or should avoid, in an actual or suspected propane emergency.
Make sure you understand and follow your company’s policies regarding communication with your customer or distribution of any safety materials.
NOTE: See Resources for a copy of the PERC Brochure: Important Propane Safety Information.
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IMPORTANCE OF GOOD DOCUMENTATION
Documenting the work you perform is a very important step each time you visit a customer location. Be certain to complete any documentation according to your company policy. If you are not sure what is required to be documented, you should contact your supervisor.
Some companies require their employees to document any communication they may have with the customer. Other companies may have limited documentation requirements.
It is important to have good documentation upon leaving a customer location. Documenting the work you performed at the time you did it in accordance with your company policies will make it more difficult for anyone to question what you did at a later date.
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MODULE 2
CHECK FOR UNDERSTANDING: PROPANE SAFETY INFORMATION
Let’s take a moment to check how well you understand the information presented in this lesson by selecting the question’s appropriate response. Check your work on page 168.
Which of the following is NOT a true statement. If you smell gas or suspect a gas leak, you should:
a. Immediately put out all smoking materials and other open flames.
b. Get everyone out of the home or building or area where you suspect gas is leaking.
c. Turn on the lights for better visibility.
d. Report the leak to the propane retailer right away.
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LESSON 4: UNCONTROLLED PROPANE RELEASE
INTRODUCTION
Propane is a safe, economical, clean-burning, and versatile fuel when properly used. Its safety record is due in part to the codes and regulations developed by the propane industry and the NFPA. Being properly trained and adhering to your company’s policies greatly help prevent propane emergencies. However, you should be prepared for emergency situations that may arise. This lesson identifies steps to take in an uncontrolled propane release.
In addition to the information in this lesson, make sure you understand your company’s policies regarding emergency response to a propane incident. The Propane Education & Research Council publication Propane Emergencies, 3rd Edition was written for emergency responders and has valuable information for propane marketers on coordinating with emergency responders prior to an emergency.
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MODULE 2
WHAT IS AN UNCONTROLLED RELEASE OF PROPANE?
For purposes of this course, an uncontrolled release of propane is one that cannot be readily shut off. Causes may include an open valve, open or damaged container component, piping failure, or container breach. An uncontrolled release of propane liquid or vapor could lead to an explosion, fire, or other emergency situation.
A propane-related emergency can occur anywhere propane is present; for example, at a residence, business, bulk plant, or en route to a location.
NOTE: Never attempt to respond to any emergency unless you have been properly trained and authorized to do so.
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WHO IS AN EMERGENCY RESPONDER?
Emergency responders include firefighters, HAZMAT crews, and emergency medical technicians. These personnel are specially trained to provide resources for fire suppression, rescue, and emergency medical triage, basic first aid, treatment, and transportation. They implement assigned tasks, provide support to specialized units, and help coordinate overall response efforts.
Because emergency responders undergo rigorous, specialized training, they are the only personnel who are qualified to provide leadership in emergency involving propane.
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MODULE 2
WHAT TO DO IN THE EVENT OF AN EMERGENCY
In the event of a propane emergency, you should always place personal safety first. This means you should:
• Evacuate the area immediately.
• Be aware of your surroundings.
• Call for help.
Let’s examine each of these in detail.
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EVACUATE THE AFFECTED AREA
If there is a propane emergency, everyone in the building or area affected by the emergency, should:
• Remain calm.
• Leave the area immediately
• Evacuate to a safe distance from a spill or leak. You should be at least 330 feet away in all directions, and for larger spills one mile in all directions.
• Evacuees should stay upwind of the emergency.
Symptoms of CO poisoning include:
Can you smell it?Propane smells like rotten eggs, a skunk’s spray, or a dead animal. Some people may have difficulty smelling propane due to their age (older people may have a less sensitive sense of smell); a medical condition; or the effects of medication, alcohol, tobacco, or drugs.
odor loss. On rare occasions, propane can lose its odor. Several things can cause this including:
• The presence of air, water, or rust in a propane tank or cylinder
• The passage of leaking propane through the soil
since there is a possibility of odor loss or problems with your sense of smell, you should respond immediately to even a faint odor of gas.
Propane gas detectorsUnder some circumstances, you may not smell a propane leak. Propane gas detectors sound an alarm if they sense propane in the air. They can provide an additional measure of security. You should consider the purchase of one or more detectors for your home.
GUIdelINes regarding propane gas detectors:
• Buy only units that are listed by Underwriters Laboratories (UL).
• Follow the manufacturer’s instructions regarding installation and maintenance.
• Never ignore the smell of propane, even if no detector is sounding an alarm.
If you smell gas1. No Flames or sparKs! Immediately
put out all smoking materials and other open flames. Do not operate lights, appliances, telephones, or cell phones. Flames or sparks from these sources can trigger an explosion or a fire.
2. leave the area ImmedIately! Get everyone out of the building or area where you suspect gas is leaking.
3. shUt oFF the Gas. Turn off the main gas supply valve on your propane tank if it is safe to do so. To close the valve, turn it to the right (clockwise).
4. report the leaK. From a neighbor’s home or other nearby building away from the gas leak, call your propane retailer right away. If you can’t reach your propane retailer, call 911 or your local fire department.
5. do Not retUrN to the bUIldING or area until your propane retailer, emergency responder, or qualified service technician determines that it is safe to do so.
6. Get yoUr system checKed. Before you attempt to use any of your propane appliances, your propane retailer or a quali-fied service technician must check your entire system to ensure that it is leak-free.
Take the sniff testScratch and sniff the blue circle. The odor is similar to propane odor. Have everyone in your family take the sniff test. Always take action if you smell any kind of foul odor.
What is propane?Propane (also called LPG—liquefied petroleum gas—or LP gas) is a liquid fuel stored under pressure. In most systems, propane is vaporized to a gas before it leaves the tank. Propane is flammable when mixed with air (oxygen) and can be ignited by many sources, including open flames, smoking materials, electrical sparks, and static electricity. Severe freeze burn or frostbite can result if propane liquid comes in contact with your skin.
to help redUce the rIsK oF co poIsoNING:
• Have a qualified service technician check your propane appliances and related venting systems annually, preferably before the heating season begins.
• Install UL-listed CO detectors on every level of your home.
• Never use a gas oven or range-top burners to provide space heating.
• Never use portable heaters indoors unless they are designed and approved for indoor use.
• Never use a barbecue grill (propane or charcoal) indoors for cooking or heating.
• Regularly check your appliance exhaust vents for blockage.
sIGNs oF Improper applIaNce operatIoN that caN GeNerate hIGh co levels:
• Sooting, especially on appliances and vents
• Unfamiliar or burning odor
• Increased moisture inside of windows
Carbon monoxide AND your safetyWhat Is carboN moNoxIde (co)? You can’t taste or smell CO, but it is a very dangerous gas, produced when any fuel burns. High levels of CO can come from appliances that are not operating correctly, or from a venting system or chimney that becomes blocked.
co caN be deadly! High levels of CO can make you dizzy or sick (see below). In extreme cases, CO can cause brain damage or death.
• headache • shortness of breath• dizziness • Nausea• Fatigue
If you suspect CO is present, act immediately!
1. If you or a family member shows physical symptoms of co poisoning, get everyone out of the building and call 911 or your local fire department.
2. If it is safe to do so, open windows to allow entry of fresh air, and turn off any appliances you suspect may be releasing co.
3. If no one has symptoms, but you suspect that co is present, call your propane retailer or a qualified service technician to check co levels and your propane equipment.
911
FD
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911
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MODULE 2
MODULE 2
BE AWARE OF YOUR SURROUNDINGS
A hazardous environment exists if you can see or smell propane. If you have an uncontrolled release of propane, do not enter or re-enter a hazardous environment. Follow your company policy regarding evacuations. When evacuating, if you can do so safely, try to:
• Identify the source of the leak.
• Check for sources of ignition and shut them off if you can do so without placing yourself or anyone in danger.
• Note the wind direction.
• Try to collect other technical information, such as the location and type of container involved, the amount of material present, and the location of shutoff valves.
This information may be helpful to emergency responders, so safely gather whatever information you can.
Next, call for help from a safe distance and outside of a hazardous environment.
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35MODULE 2
CALL FOR HELP
After you are at a safe distance from the affected area, call 911. You should also notify your supervisor as soon as you can.
When you call 911, be ready to provide the following information:
• Your name.
• Your company’s name.
• The address of the emergency location.
• Your contact information, such as a cell phone number or a phone number nearby, and any obvious injuries needing immediate attention.
• A brief summary of the emergency. For example: Is there a leak, and if so where? What kind of container is on site, and what size is it? Is the area densely populated or rural? Has anyone been injured? If so, how many and to what extent?
After you call for help:
• Do not endanger yourself or others.
• Assign someone to meet and direct emergency response units to the scene.
• Call back from a safe distance if the situation changes before emergency responders arrive.
• Stay away from any unknown materials such as unknown chemicals at industrial plants.
NOTE: Remember, any uncontrolled release of propane can be extremely dangerous. If you suspect an emergency, immediately evacuate the area and call for help.
911
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MODULE 2
WHEN HELP ARRIVES
Once the emergency response team arrives, do not interfere. They may ask you about certain physical and chemical properties of propane, and to assess hazards and identify risks. They may also ask you to provide other information such as the location and type of container involved, the amount of material present, and the location of shutoff valves. If you have this information, you should provide it. If not, you should tell them you don’t know.
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POST EVENT ACTIONS
After an emergency has been resolved, there may be an official investigation. You could be interviewed as part of the investigation. You should support this effort in accordance with your company policy.
Many companies designate spokespersons who are authorized to address the news media. If you are not authorized to speak to news media on behalf of your company, you should refer all media inquires to your company management.
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MODULE 2
MODULE 2: SUMMARY
KEY POINTS TO REMEMBER FROM THIS MODULE ARE:
• Propane will burn when mixed with the proper amount of air.
• Propane liquid vaporizes into a gas when container pressure drops.
• It is important to understand specific gravity of propane vapor when trying to find the source of a leak or when working in an area where a leak has occurred.
• The boiling point of propane is so low, -44° F, that it will boil at normal temperatures most anywhere on earth.
• Propane is affected by heat and pressure in much the same way as water.
• Containers are generally filled to about 80% of their capacity to account for effects of pressure and temperature.
• Propane liquid expands in volume nearly 17 times greater than water even when they are exposed to the same increase in temperature.
• If the pressure inside the container becomes too high, then the relief valve discharges propane vapor and reduces the pressure to a safe level.
• Propane containers should always be stored upright and outside because of the effect that heat can have on the propane.
• It is very important that the correct steps are followed if you smell gas or suspect a gas leak.
• Any time a gas distribution system loses gas pressure, a service interruption occurs. Therefore, it is very important that all gas service interruptions be handled properly.
• Make sure you understand and follow your company’s policies regarding communication with your customer or distribution of any safety materials.
• Propane is a safe, economical, clean-burning, and versatile fuel. However, because it is flammable, emergency situations can and do arise. You should never attempt to respond to any emergency unless you have been properly trained to do so.
• In the event of an emergency, you should evacuate the area, be aware of your surroundings, and call for help. You should also notify your supervisor as soon as it is safe to do so.
MODULE ?
SAMPLE CONCLUSION
GET THE FULL COURSEFor modules 3-8, as well as resources including quizzes, videos, student materials, and more, download the full course here, or visit PropaneProfessional.com.
Propane Education & Research Council
1140 Connecticut Ave. NW, Suite 1075, Washington, DC 20036
Telephone: (202) 452-8975 | Fax: (202) 452-9054
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