08.1 – Mechanical Examples
In this section lets look at some examples of mechanical lockout devices and their applications. Note the red highlighted examples showing cautions and dangers to consider when applying lockout devices.
Valves on a pipe run (nipples) can often be involved in a lockout as an ‘open to atmosphere point. In this case if they MUST be open for the lockout, they may likely be LOCKED OPEN.
Valve covers (in this case a GATE VALVE DEVICE) are used to prevent the turning of the handle once the valve is in the ‘state’ desired for the lockout.
CAUTION!
One thing that cannot happen as part of performing a lockout, is to create hazards for other worker(s). In this example, if ONLY the valve on the left was to be locked out, the applier of the cable and lock created a danger or risk in the facility by capturing the other valve in the process. If this same left-only lockout is required, put the cable around the stem of the other lock or the pipe to prevent introducing other hazards.
Hasps are useful in any application when potentially more than one lock may need to be applied.
This example is a solenoid control of a PVC ball valve.
NOTE: software control is NOT lockout, all solenoids still need a physical disconnect device applied.
This type of lockout device is very flexible in its applications. There are pros and cons to this device
Pros:
• It fits many different sizes of valves easily
• It is a ball valve lockout device that can allow partial open or closed states or even ranges of states depending on where you put the ‘peg’ stops
Cons:
• does not cover the nut on the handle or provide extra security
• is possible for the ‘pegs’ to bend or move position
• does not have a built-in hasp
This type of ball valve cover is very strong but has some limitations.
Pros:
• Is very strong and completely covers the valve handle and body
• Has a hasp built in
• Prevents tampering with lock itself and will not shift from it’s position
Cons:
• is limited in the size of valves it can handle – you may need several different sizes of these depending on your applications
• Can only lock valve in two positions – full open or full closed
