For more than four years, EPA rules have required remodelers to be lead safe certified to conduct that kind of work. But I guess some people haven't gotten the message yet.

Call your local EPA field office and file a complaint. An inspector will be dispatched forthwith in most instances.

If she hasn't already taken action, have her check out the Alameda County Healthy Homes resource list (linked below). She can also contact their help line, but it's likely that her first step will be to call her city (or the County if she is in an unincorporated area), who will send an inspector out and probably put a stop work order on the painting until there are lead containment practices in place. She can also report it directly to the EPA (there's a form online) but I suspect she'll get faster action by calling the local jurisdiction.

Pretty much every house of that age in the area has lead paint on the exterior (if the original exterior hasn't been replaced with asbestos shingles--even better!) and usually the interior too, so it is a common problem, but there are some clear abatement techniques that contractors are required to use. If the owners aren't using a contractor trained in the techniques they will need to find someone who is.

Here is a link that might be useful: Lead Resource Info

EPA RRP regs require exterior painters to cover the ground with sheeting ten feet from the perimeter of the work area. EPA has and will levy major fines against painters who do not follow the regulations.