1-junior high age and up; no language barriers; minimal cross-cultural setting; no missions experience required
2-junior high age and up; moderate language barriers; moderate cross-cultural setting; missions experience helpful
3-senior high age and up; some language barriers; challenging cross-cultural setting; missions experience helpful
4-adults (some mature senior high); increased language barriers; intense cross-cultural setting; missions experience required

L=LOW RISK (western country or major city in developing world)
I=INTERMEDIATE RISK (developing country, travel outside city)
S=SUBSTANTIAL RISK (few western amenities, marginal medical system, political unrest sometimes present, possible infectious disease)
H=HIGH RISK (few western amenities, marginal medical system, travel to remote areas, environmental extremes/altitude, heat, etc, infectious disease)
Pregnant women are not permitted to participate on projects rated as Intermediate, Substantial or High Risk.