1990s, Photograph, Spirometer Spirometer, Brentwood Spiroscan 1000 January 24, 2014 Richard Johnston Leave a comment Brentwood Spiroscan 1000. Pneumotach based. Manufactured by Hoks Electronics Inc., Japan, for Brentwood Instruments Inc. around 1990. From: http://www.dotmed.com/listing/spirometer/brentwood/spiroscan-1000/1462361