The right of Conscientious refusal is the right to refuse to engage in unethical behaviour and to refuse to do so solely because one views it as unethical.
Two situations to be considered.
1. Where there is widely shared agreement in profession as to whether an act is unethical
Here, professionals have a moral right to refuse to participate in such activities.
2. Where there is room for disagreement among reasonable people over whether an act is unethical.
Here, it is possible that there could be different ethical view points from the professional and the employer.
In such cases the engineers can have a limited right to turn down assignments that violates their personal conscience only in matters of great importance such as threats to human life.
This right also depends on the ability of the employer to reassign the engineer to alternate projects without serious economic hardships to the orgn.
The right of professional conscience does not extend to the right to be paid for not working.