Chaplaincy is definitely a full-time job. In jails the rolling population might be a single chaplain and hand full of volunteers managing a rolling population of 1,000. By that I mean that of the 1,000 people incarcerated at a facility at the city or county level at a given time, many will be awaiting trail or transfer to another jurisdiction, or serving sentences from 30 days up to 1 year, 11 months, 29 days and then rolling out. This means lots of folks are in a state of nearly constant transience and distress and with little time to develop the kinds of relationships that pay the highest dividends. This is particularly frustrating because these are folks who are front-line with first-time offenders where intervention could be most effective. And some do, by God's Grace, make significant impacts even in such chaotic circumstances. At state and national prisons the population may be more stable, but, like local chaplains, they have four major jobs, (1) pastor, (2) volunteer recruiter, trainer and coordinator; (3) fundraiser or budget advocacy, and (4) maintaining the relationship with the administration of the facility.
If you have the opportunity to buy tickets to a fundraising dinner or play in a fundraising golf tournament for these folks, or asked to contributed support, please do so. They are, in my experience, very good stewards of these fund. If you have a desire to volunteer, be prepared to be persistent and provide references from your home congregation or civic organization, or better yet, offer to become the prison ministry coordinator for your church. Chaplains need help, but they also must be cautious about folks who volunteer both because they might not be who they purport to be and harmful to an already fragile population, but also because Chaplains have limited time for training volunteers and they need volunteers to come with a commitment to stick around for a while.
Volunteers can do office administration tasks, help with fund raising, volunteer recruitment and training, Bible studies, grade Bible study papers, conduct classes in family financial literacy, basic reading, parenting, and decision making skills, conduct AA or CR meetings, administer pen-pal programs, serve as pen-pal or mentors, and many other tasks either enhancing the amount of contact with inmates or relieving the chaplain from administrative tasks.
At all times please keep chaplains in your prayers. It is a challenging job with about as much social cachet as funeral directors and pay that is often less than a grade school custodian. But they are a life-line to our loved ones behind bars and serve to remind all within the facility walls that the light of Christ shines greater than the darkness.