Re: Refrigerator Cars - Salt Water Drippings
Corrosion from salt melt was a significant problem for railroads. This was because all reefers could have salt added to the ice for lower temps. That was the purpose of ice. Meat required a lot of salt as shippers wished to ship meat at temps in the mid 30s. Many produce and dairy products were shipped with temps in the 40s, but some required temps in the 30s, and frozen times required temps in the 20s or lower, increasing the required salt amounts.
Meat reefers different from other reefers in one important area, the ice bunkers were sealed from the load area. And there was no fan to circulate the cold air. This prevented the meat from getting contaminated from water and salt melt. Meat never came in direct contact with ice, as in blowing in ice to top the load.
Many meat reefers and some other reefers had brine tanks (but not all) meaning the ice bunkers were sealed so no salt melt dripped out or entered the reefer interior. The bunker drains had plugs, which were only opened at proper facilities equipped to handle the salt melt. Often when opened the drains were plugged with ice and salt requiring the carmen to beat open the drains when the plug was removed.
Traditional ice bunker reefers had open drains that dripped water (and salt) on the ROW, the undercarriage, etc.as the ice melted. These bunkers also had screened openings into the reefer interior, allowing better air flow but also allowed water to enter the car interior. This is one reason reefer floors had ribs or slats, to allow ice melt water to flow and drain. It also allowed ice blown in on top of produce to melt, drip to the floor and drain via the bunker drains.