Purging and Safety Guidelines

Important Information for Propane Retailers: Purging and Safety Guidelines

Revised 2023-11-14

Introduction: Welcome to James River Manufacturing, your trusted propane tank supplier. We want to ensure your safety and the safety of your customers. In this guide, we will explain our purging process, how to verify pressure, and address the use of Methanol and Ethyl Mercaptan.

1. Purging Process: James River sends vacuum-purged tanks to prevent air and moisture from entering, which can corrode the tank. We do not introduce any gases. Please check for a vacuum in the tank upon arrival. Consult a CTEP trained propane professional to purge and install tanks using NFPA 58 guidelines.

2. Verify Pressure: Upon receiving a propane tank from us, check the pressure. Avoid opening cylinder service valves. Use a POL test-gauge block and follow these steps:

Install the pressure block and seal it in the service valve.
Open the service valve and check the pressure gauge.
- Negative reading: The cylinder is purged.
- Positive reading: The cylinder requires purging.
If in doubt, purge the cylinder.

3. Purging a Tank: As per NFPA 58, any new or reconditioned ASME container exposed to the atmosphere should be purged. Two methods are suggested:

Choice 1: Vapor Purge Method: Ensure safety in a well-ventilated area and follow specific steps.
Choice 2: Vacuum Purging Method: Utilize a suitable hose and follow the steps mentioned.

4. Methanol Use: Methanol can prevent freezing in the propane stream. We do not add Methanol. Follow your company's policies for adding Methanol. Here are suggested amounts based on container capacity.

5. Gas Injection Process: After Methanol injection, connect a hose from an LPG source to the POL connection of the service valve to neutralize the vacuum pressure. The amount of LPG required depends on the vessel's volume.

6. Filling Process: After the LP Gas injection process, close the service valve, disconnect the POL connection, and proceed to fill the tank. Ensure the first fill is to the maximum liquid level to prevent odor fade.

7. Odorant and Odor Fade: James River Manufacturing does not introduce Ethyl Mercaptan. Ethyl Mercaptan is added by terminals, and NFPA 58 has codes for propane retail marketers. Ensure the presence of odorant by performing a sniff test before final delivery.

Safety Notice: Failure to purge a container properly can result in increased pressure, improper burning fuel mixture, and odorant fade, which may lead to personal injury, property damage, or even death. Always follow safety procedures and consult professionals when in doubt.

Thank you for choosing James River Manufacturing as your propane tank supplier. Your safety and the safety of your customers are our top priority. If you have any questions, feel free to contact us.

Purging A Tank

See NFPA 58 for current purging instructions

NFPA 58: 12.3.2.5

A new or reconditioned ASME container, or an ASME container that has had its interior exposed to the atmosphere, shall be purged and have contaminants removed prior to being filled with LP-Gas.

Suggested Container Purging Steps

NFPA 58: Annex M:

Introduction

In accordance with 12.3.2.5, all containers that have had their interiors exposed to the atmosphere (that would occur during a service valve change) are to be purged of air and other contaminants. The following methods have been found to be effective.

Choice 1: Vapor Purge Method

This procedure should be performed in a well-ventilated and non-enclosed area and at least 35 ft (11 m) away from potential sources of ignition.

The method steps are as follows:

Position the container so that a manually operated (nonelectrically operated/solenoid) valve, installed within the vapor space, is at the topmost portion of the container or in the highest portion of a manifold ASME container.

Using a regulated LP-Gas vapor source, introduce 20 psig (138 kPag) of LP-Gas vapor into the container.

Allow the pressure to stabilize for approximately 5 minutes.

Release the gas until the pressure is between 3 psig and 5 psig (21 kPag to 34 kPag), in accordance with local hydrocarbon emissions regulations and 7.3.1.

Repeat the process a minimum of five times, to ensure that almost all of the air has been removed from the container, and the moisture content has been reduced.

Close the manual valve to prevent re-entry of moisture and air.

CAUTION: This purging method must be followed precisely on containers using internal electronics/electrical circuits to ensure that a combustible mixture of fuel and air cannot be present before energizing electrical circuits.

Choice 2: Vacuum Purging Method

The vacuum purging method steps are as follows:

Use a hose suitable for vacuum service to connect a compressor to the ASME container.

Ensure that any protective caps for appurtenances are in place and tightened.

Open the service valve and run the compressor to reduce the pressure in the ASME container to a vacuum of 26 in. Hg (−88 kPa).

Close the service valve and disconnect the compressor.

Note failure to properly purge a container can result in increased pressure, improper burning fuel mixture, and odorant fade. Any of these conditions can result in personal injury, property damage or death.