I worked for a company that made household and commercial cleaning products. Some of these products were liquid in plastic bottles, glass bottles, gallon and larger containers. The majority of these products were water based and susceptible to freezing. We also had a lot aerosol products and they needed to be protected form freezing too. For this reason we used insulated box cars to maintain a warm environment for our products. These products were shipped all over the United States all year long.
Once we got a mechanical reefer loaded with our product. Someone decided to turn on the reefer unit while the car was in transit and froze up the entire railcar of product. Needless to say the carload of product was scrap.
Periodically we would put a temperature recorder in a railcar when it was loaded. These recorders are battery operated and record the car temperature while the car is in transit. The recorder scribes a line on a roll of graph paper while the recorder is turned on. Upon reciept at the receiving destination the batteries were removed and the batteries and recorder were sent back to the main plant via UPS.
We had simialr recording devices to record shock or excessive jarring of the car that might cause damage to the product within the car. A lot of times the hump yard switching could cause damage to the car and contents.