Workers exposed to various irritants are widely advised to use moisturizers. To evaluate the efficacy of a moisturizer (Locobase), we studied 111 cleaners and kitchen workers during everyday exposure to water and detergents. All took part in a standardized interview. After randomization, 1/2 the workers (n = 56) used Locobase during a period of 2 weeks (period L), followed by a period without any emollient (period C), or vice versa (n = 55). Clinical assessment and measurements of the skin surface temperature, electrical capacitance and transepidermal water loss (TEWL) were performed on the fingers, hands and arms on entry to the study, after 2 weeks and 4 weeks, or at drop out. The final evaluation showed that 70 (63%) were able to complete the study; 23 (21%) completed period L, but withdrew from period C after a mean of 6 days because of progressive dryness of the skin and eczema; and 12 (11%) were excluded because they used topical corticosteroids or emollients. The remaining 6 (5%) participants were lost to follow-up. Clinically, we observed a significant increase in dryness (p < 0.001) during periods of no treatment (period C), and normalization of the skin texture during use of Locobase. Clinical observations were confirmed by statistically significant differences (p < 0.001) in the electrical capacitance (epidermal hydration), which decreased during period C and increased to pre-study values during period L. No significant differences were found in skin temperatures and TEWL rates.(ABSTRACT TRUNCATED AT 250 WORDS)