External infusion device with a vented housing

An external infusion device for infusion of a fluid into a body from a reservoir, the external infusion device comprising:

• a drive system to operatively couple with the reservoir to infuse the fluid into the body;
• a housing adapted for use on an exterior of the body, wherein the housing is sized to contain at least a portion of the reservoir, wherein the drive system is at least partially contained within the housing, wherein the drive system operatively couples with the at least a portion of the reservoir within the housing, and wherein the housing is sized to be carried by a user without significant restriction on mobility;
• and
• electronic control circuitry coupled to the drive system to control infusion of the fluid into the body;
• wherein the housing has at least one vent port covered with a hydrophobic material that permits the passage of air into and out of the housing and inhibits the passage of liquids into the housing through the at least one vent port covered with the hydrophobic material such that air pressure within an interior of the housing but external to the reservoir is equalized with air pressure outside of the housing by the passage of air into and out of the housing through the hydrophobic material,
• the hydrophobic material being formed as a sheet attached to the housing and applied over the at least one vent port.