What are the arguments for and against Voluntary   Service by engineering professionals?

Should engineering professionals offer engineering services to the needy, without charging fee or at reduced fee?

Voluntarism of this kind is already encouraged in Medicine, Law and Education.

But  ABET  code  states  “Engineers  shall  not  undertake  or  agree  to  perform  any engineering  service on a free basis” and other codes also insist that engineers  are obligated to adequate compensations (which means full fee)

Engineers find it difficult to donate their services individually compared to doctors and lawyers since their output is on a shared basis

But,  as  suggested  by Robert  Baum,  engineers  can  volunteer  their  services  in the following areas, in groups, either free or at cheaper than normal fee.

Environmental impact studies that is harmful to a community

Health issues of polluted water and soil

Minimal needs of elderly and minorities like running water, sewage systems, electric power and inexpensive transportation.