Code of Federal Regulations Title 41. Public Contracts and Property Management § 41.301–2.5 What travel arrangements require specific authorization or prior approval?

(a) Use of other than coach-class service on common carrier transportation;

(b) Use of a foreign air carrier;

(c) Use of reduced fares for group or charter arrangements;

(d) Use of cash to pay for common carrier transportation;

(e) Use of extra-fare train service;

(f) Travel by ship;

(g) Use of a rental car;

(h) Use of a Government aircraft;

(i) Payment of a reduced per diem rate;

(j) Payment of actual expense, unless your agency has issued a blanket actual expense authorization under § 301–70.201;

(k) Travel expenses related to emergency travel;

(l) Transportation expenses related to threatened law enforcement/investigative employees and members of their families;

(m) Travel expenses related to travel to a foreign area;

(n) Acceptance of payment from a non–Federal source for travel expenses, see chapter 304 of this subtitle;

(o) Travel expenses related to attendance at a conference;  and

(p) Due to an employee's medical requirements or religious beliefs, payment of the full M & IE allowance even though meals are furnished by the Government either directly or through a registration fee or other payment for a conference or other event, in accordance with § 301–11.18(b).