A disposable apparatus for propelling particulate matter against a surface of a target material that includes: a
mixing chamber having a chamber wall, a multi-conduit receiving port, a
propellant-gas receiving conduit, and a
discharge conduit. The gas delivery conduit extends from the
propellant-gas receiving port into the chamber, a mixture
discharge conduit extending from the mixture
discharge port into the chamber, and a quantity of particulate matter inside the chamber. The disposable apparatus further includes a membrane capable of allowing a gas
stream to pass through when the gas
stream is flowing and seals the
mixing chamber when the gas
stream is not flowing. The membrane can be of a hemispherical shaped, molded piece that includes at least one slit to provide an opening when the gas stream is flowing. A method is provided for propelling particulate matter against a surface of a target material using the above-described apparatus, including the steps of delivering a stream of gas into the air delivery conduit and into the
mixing chamber from the gas source, so that the gas stream blows through the quantity of particulate matter, causing the particulate matter to mix with the gas stream, forming a gas and particle mixture, and discharging the mixture through the discharge conduit and the discharge port to strike the surface of the target material. The method further provides a means for automatically containing the particulate matter within the mixing chamber when the apparatus is not in use.