Preliminary findings were reported for an investigation in Rhode Island of an outbreak of interstitial lung disease (ILD) among workers involved in the manufacture of finely cut nylon (flock) and flocked fabric. In November of 1994, a 35 year old textile worker presented for evaluation of chronic ILD. To identify additional ILD cases among the 127 current production workers at the facility, all employees with persistent respiratory symptoms were encouraged to undergo full pulmonary function testing, chest radiography, and high resolution computerized chest tomography (HRCT). Transbronchial or wedge biopsy was performed for those with unexplained restrictive lung function, impaired diffusing capacity or HRCT findings consistent with ILD. The study cohort, 165 persons, also included some former workers. Seven of the cohort were identified with flock worker's lung. Their mean age was 41 years. Two were current smokers, four had discontinued smoking more than 18 months earlier, one had never smoked. The median latencies from time of hire to onset of symptoms and from onset of symptoms to time of diagnosis were 6 years and 1 year, respectively. Tissues obtained demonstrate nonspecific interstitial pneumonia in five patients and bronchiolitis obliterans organizing pneumonia in the sixth. All had nodular lymphoid infiltrates, four had germinal centers. Preliminary air sampling at the facility revealed extremely high short term total dust concentrations up to 83mg/m3, only modest concentrations of fungal spores and endotoxin, low levels of volatile organic compounds, and negligible concentrations of metals.