Mark 3 Capacity Cheat Sheet
18,000 feet and 2,000 feet of head, 60 GPM. How many mark 3's Required?
Iphone and Android viewers will need a PDF viewer to download the Cheat Sheet.
Simplified sheet (download link to 8 page PDF inside) to help folks with what we in wildfire deal with all to often but hardly have any instruction on how to be fast, accurate and efficient with setting up Mark 3 pumps on long hose lays.
This example used a design a former student put together for a fire in New Mexico this past season and although they had a changing of a IMT, this is the process that I worked out that anyone could do quickly in the field. There are three (3) caveats to this.
This method assumes a constant slope ratio. That is from start to target a continuous slope and no dips in the middle. If you have such on your fire, then break up the hose lay into “legs” each with their own slope ratio. Doing so will “Ensure” you are accurate. Otherwise things will NOT work as you think they will.
As most if not all of the Mark 3 pumps out there do NOT have discharge pressure gauges, it is HIGHLY recommended that you order some inline pressure gauges and attach this to the discharge port of the Mark 3. These gauges “must” be capable of 0-400 psi range. If, however, the inline gauge you obtain does not go to 400 psi, I would recommend you obtain a glycerin filled gauge and install it!
Make sure that if you use this method that you are both thinking of and taking advantage of the parallel (Siamese) hose lay methods for best results and greatest distances.
If you like the information perhaps consider buying me a coffee by the link on this site.