If you're Rh negative and your baby is Rh positive, however, your body might produce proteins called Rh antibodies after exposure to the baby's red blood cells. The antibodies produced aren't a problem during the first pregnancy.he Rh factor test is done during pregnancy to identify a woman's Rh factor. In some cases, the baby's father might need an Rh factor test, too. During pregnancy, problems can occur if you're Rh negative and the baby you're carrying is Rh positive.
Torque converter, opened, interior similar to a retarder. A retarder is a device used to augment or replace some of the functions of primary friction-based braking systems, usually on heavy vehicles. Retarders serve to slow vehicles, or maintain a steady speed while traveling down a hill, and help prevent the vehicle from running away by accelerating down the hill.
condensation control can be accomplished by venting the cavities of the walls and roof. Vapor Retarders A vapor retarder is used to inhibit the passage of warmer moist air into the inner regions of the roof or wall system. The proper selection and installation of the vapor retarder can help control condensation problems in a building. Vapor retarders are rated by the amount of moisture that can pass through them. The lower this rating, called a perm rating, the less vapor transmission will occur and the more effective the vapor retarder will be. Water vapor transmission rates (perms) are determined using ASTM E 96, Standard Test Methods for Water Vapor