"The Block 1 SLS is the 'basic model,' sporting a Delta Cryogenic Second Stage (DCSS), renamed the Interim Cryogenic Propulsion System (ICPS) for SLS. The current plan calls for this [interim] stage to be used on [the unmanned] Exploration Mission -1 (EM-1) and [manned] Exploration Mission -2 (EM-2), prior to moving to the [Exploration Upper Stage] — also to be built by Boeing — that will become the workhorse for SLS. However, using the [interim upper stage] on a crewed mission will require it to be human rated. It is likely NASA will also need to fly the [Exploration Upper Stage] on an unmanned mission to validate the new stage ahead of human missions. This has been presenting NASA with a headache for some time, although it took the recent ASAP meeting to finally confirm those concerns to the public."
NASA doesn't have the funds to human-rate it, and even if they get those funds, human-rating it will likely cause SLS's schedule to slip even more, something NASA fears because they expect the commercial manned ships to be flying sooner and with increasing capability. The contrast — a delayed and unflown and very expensive SLS vs a flying and inexpensive commercial effort — will not do SLS good politically. However, if they are going to insist (properly I think) that SpaceX and Boeing human-rate their capsules and rockets, then NASA is going to have to hold the SLS to the same standard.
Members of the union perform a wide variety of tasks, everything from fighting food-borne illnesses to mopping up the Refugio State Beach oil spill. For example, Cassandra McQuaid left a job last year at the Department of Public Health's state-of-the-art Richmond laboratories where she tracked foodborne illnesses. It's the kind of vital, behind-the-scenes work that goes unnoticed until an E. coli outbreak makes headlines and local health officials need a crack team of scientists to unravel how it happened. "It really came down to money," says McQuaid. "I just couldn't live in the Bay Area on a state salary."