Testing kits can be bought from some Trade counters, and Merchants. Lead based paint becomes dangerous when it starts to deteriorate. Paint flakes and dust can then be taken in through the mouth or lungs. Dry sanding is dangerous. Protective gloves, overalls, and mask, when dealing with lead paint are essential.
Safe removal is based on keeping debris as coarse as possible, and contained.
Carpets and material that would harbour dust are cleared from the work area. Surfaces are covered with heavy gauge plastic sheet. Wet sanding, or chemical stripping, are the least hazardous ways of removing the paint. Great care must be taken in disposing of the debris. It should not be burnt, or composted.