Do you need to take an RMD?

April 1 is the last day you can take your required minimum distribution (RMD) for 2017 from your traditional IRAs. If you reached age 70½ last year, this is a big deal.

April 1 is the deadline for retirement distributions

You may be approaching an important deadline if you have retirement accounts and you turned 70½ last year. Generally, you must begin withdrawing money from tax-favored retirement plans in the year you turn 70½. However, you may postpone your first withdrawal until April 1 of the year after you turn 70½. That means you have until April 1, 2015, to complete your required 2014 distribution.

Can a Self-Emplyed person, who is still working full-time skip thier Pension/IRA RMD (Required Minimum Distribution)?

No. Generally, you must begin taking "required minimum distributions" (RMDs) from your qualified retirement plans and IRAs after you turn age 70 1/2. Then you must continue taking RMDs for each succeeding tax year.
However, you can delay RMDs from qualified plans if you're still working full time and you don't own 5% or more of the company.  There is no such exception for IRAs. Because your Simplified Employee Pension (SEP) is treated as an IRA rather than a qualified plan, you must start taking RMDs after you turn 701/2 whether you are still working or not.

So, remeber: In any event, full-time workers can't postpone RMDs from an IRA.