off the top of my head, i can't think of this clearance. your customer will give you all the clearance you are needed to do business with them. they'll do face time on their site, your site, or a restaurant in between as long as you're buying. they'll give descriptions of what they need so you can supply it. as far as nuclear technology prowess is concerned, if that be your anticipated need for doing business, i'd suggest hiring someone with degrees in the field and contacts in the business. recent retirees from the client of concern are an excellent trolling ground for prospects.