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Guidelines for operation of Live Steam locomotives at KLS.

These guidelines provide info and details of locomotive operation beyond that defined in the KLS Conduct of Operations document.  If conflicts exist, the Conduct of Operations document is the final authority.

Sight Glass testing and operation. 
The following document explains the process for testing a sight glass.  Testing your sight glass should be done on periodic basis during a run day.  A suggestion would be to check at startup and when refilling the tender during the run day.
Sight Glass testing procedure

Boiler blow down
To prevent damage to a boiler it is recommended to not perform a blow down when the boiler's current pressure is above 50psi.  To gain the most benefit of cleaning a boiler via blowdown, it is best to not add obstructions to the blowdown valve.  However, when blowing down in the steaming bays to drain a boiler, use of a muffler to minimize noise and contain the water expelled from the boiler is required.  If it is not possible to attach a muffler to your locomotive, See Don Rogers ( for other options.

Pre-certified boiler inspection
Important notice: As of 1/1/2020 - Because doing a cold water hydrostatic test on our pre-certified boilers is no longer recommended except by state certified boiler inspectors, Kitsap Live Steamers will no longer preform the hydro test as part of our annual live steam engine self-test.

Kitsap Live Steamers requires an annual inspection of the safety devices on a Live Steam Locomotive prior to operating on the KLS track.  KLS does not "test or inspect" boilers as we are not qualified to do a metallurgical or stress test of an existing boiler.  The safety inspection verifies the operation of the pressure gauge, safety valves, sight glass and water supply devices.  The inspection is performed by the locomotive's owner and witnessed by one of the following KLS members as of 3/1/2023: Ken Olsen, Bill Hartung, Ted Karanson, Tom Huffman, Russ Noe (Southern WA & Northern OR), Christopher Brew, John Bartlow, Ryan Handle (WA North of King County).  Contact info for these members can be found on KLS website.

Below is a sample of the form to be filled out during the inspection.

KLS Boiler Check and Witness form rev 4-8-21-2 no watermark* This form is for reference only!
New boiler (or new to WA state) certification process:

As of XX/XX/XXXX, the following steps need to be completed by the owner of the boiler to receive a Washington State boiler certificate.
1.  Complete the following documents
Boiler form to be completed for hobby boiler certification
Sample of a completed form to prepare for boiler certification
Miniature Hobby Boiler Guidelines

2. Make an appointment with their local boiler inspector to have the boiler certified.
contact information:
The following page The Board of Boiler Rules ( provides contact information for the WA Dept of Labor & Industries Boiler board members.

Contact Mike Carlson at 360-902-4983 to find out the contact information for your local inspector. Ask the local inspector for their contact information so that you can send them copies of your documents prior to the inspection date.

3. Meet with inspector. 
When you meet with the inspector, you will be asked to fill the boiler with water until it is completely full. Then you will need to pressurize the boiler with a suitable pump and pressure gauge until it reaches 1 1/2 times the calculated Maximum Allowable Working Pressure based on your calculations. If it is not a new boiler, it will be 1 1/4 times the MAWP. If your pressure gauge is less than this pressure, be sure and remove it before doing this. Then you will need to fire up the boiler so that the inspector can check to see if the safety valve(s) release at about 5 psi under the MAWP. If two valves, which some tracks require, one should release before the second, usually a 5 psi difference. The boiler inspector will give you the boiler number and you will be billed for this service. Once the bill has been paid you will receive the certificate for this boiler. 

Based on the current code, once you have the hobby boiler certified, you are not required to have it inspected again by the state. However, most model railroad clubs require you to show that you have proof of a current self-test of the boiler to run on their track. Kitsap Live Steamers in Port Orchard, WA, Great Northern and Cascade Railroad in Skykomish, WA as well as Train Mountain Railroad in Oregon are examples. 
Jeff Mills
So!  You want to Buy a Scale Steam Locomotive

This article was written by Jeff Mills in March 2023.  It contains information and things to look out for when considering purchasing a used live steam locomotive.

Buying a used live steam locomotive

Additional information and resources for Live Steam locomotives

Below are links to various documents that may be useful in the process of designing and certifying a boiler for your locomotive.

2010 ASME Boiler & Pressure Vessel Code Sec 1
RCW 70.79.080 Exemptions from WA boiler chapter
ASME Boiler & Pressure Code Section IV 2007
Washington State Boiler Code 2018

Other information on hobby boilers that may be of interest:
Firing up a Steam Locomotive
Running a Live Steam Locomotive
LSB 8000 Instructions
Live Steam Boiler Treatment
Safety Valve Cleaning by SuperScale
Super Scale Safety Vales setting

Information on Injectors for maintaining water in a live steam boiler
Anthony Duarte at Eccentric Engineer has produced a short video showing ways that an injector can fail and the modifications needed to correct the problems. Eccentric Engineer Injector Solutions

Reference book: "The Backyard Railroader: Building and Operating a Miniature Steam Locomotive" by Jeff Frost


Live Steam Locomotive Owners 

Check out this guy's boiler problems: 

Forms for New Boiler Inspections:
Boiler Calculation Report
Miniature Hobby Boiler Guidelines
Boiler report for Ken's Pacific

Links on info related to why KLS no longer does a hydro test on hobby boilers.
Boiler Hydrostatic Testing - ASME (mechanical) Code Issues - Eng-Tips
Boiler Testing
Effect of hydrotest on component stress - Boiler and Pressure Vessel engineering - Eng-Tips
The National Board of Boiler and Pressure Vessel Inspectors
National Board of Boiler and Pressure Vessel Inspectors
ASME hydro testing instructions
Effects of hydrotest on component stress
What is boiler accumulation test
Thin Wall concept (Why model boilers are stronger than full size RR boilers)