Airflow Meter. An airflow meter measures air velocity as well as air pressure. Depending on the type of application, the airflow meter is made as a hot-wire airflow meter, a vane airflow meter, a cup anemometer, a Pitot tube air flow meter or a pocket weather flow meter, all of which can measure air velocity as well as air pressure. Some can even detect the wind direction.
While hemorrhoids can bleed, the amount of actual blood loss is typically slight, so anemia is very uncommon with bleeding hemorrhoids. If you are on blood thinners, such as Aspirin and warfarin, the bleeding might be more impressive, but again anemia would be unexpected.
1 It causes no symptoms unless there is bleeding with a bowel movement, or if it prolapses and can be felt externally after if protrudes through the anus.  An external hemorrhoid arises from blood vessels that surround the anus beyond the pectinate line. They do not cause many problems unless they rapidly expand and clot.