Depending on the vaccine to be used, there are different guidelines set out by the Center of Disease Control (CDC). The most fragile of vaccines that must be have special attention are live attenuated vaccines. These live vaccines are derived from disease-causing viruses or bacteria. Before they are administered in treatment, they are attenuated, or weakened, in a laboratory. Although live attenuated vaccines will begin to replicate in humans when administered in treatment, they the disease state is much milder compared to the natural disease state. These types of vaccines are extremely fragile because they have been taken out of their native state and mutate. As a result, proper handling must ensure that the vaccines remain out of high heat or light. Examples of live attenuated vaccines include measles, mumps, and rotavirus.

For other less fragile vaccines, the CDC recommends a series of guidelines for referigeration or freezing. Importantly, they have come up with a "Toolkit" as a means of outlining how health care organizations should distribute and maintain vaccines. The general outline is called a "Cold chain flow chart." This chart as shown below highlights each stage of vaccine production from manufacturing to administration. 

At each of these stages, the CDC ensures that the vaccine to be produced is well-insulated so that it will not degrade.

Finally, since vaccines are particularly important for young children, the American Academy of Pediatrics has come up with their own table and chart for vaccine storage. These guidlines are to be maintained through hospital systems to ensure that vaccinations can be performed consistently and efficiently. Ultimately, the production of vaccines is a multi-step process that involves a series of checkpoints to ensure that the vaccine can be fully functional by the time of administration. Depending on the type of vaccine used, there can be different guidelines outlined by the CDC. 

Resources: 

http://www.cdc.gov/vaccines/hcp/admin/storage/toolkit/storage-handling-toolkit.pdf

http://www.cdc.gov/vaccines/pubs/pinkbook/prinvac.html

http://www.cdc.gov/vaccines/hcp/admin/storage/toolkit/storage-handling-toolkit.pdf

https://www.aap.org/en-us/advocacy-and-policy/aap-health-initiatives/immunization/Pages/vaccine-storage-chart.aspx?nfstatus=401&nftoken=00000000-0000-0000-0000-000000000000&nfstatusdescription=ERROR%3a+No+local+token