Patient room cleaning
cleaning product , Patient room cleaning involved combination of several cleaning tasks, such as floor, counters and bathroom cleaning tasks. An example of a patient room cleaning flow chart is given in Figure 1. The workers were responsible for cleaning a certain number of patient rooms (in one case, 22 rooms) during the work shift.
Process flow diagram of the tasks performed for patient room cleaning. The shaded boxes indicate cleaning tasks/steps with higher potential for inhalation exposure.
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Inhalation exposure potential
Qualitative exposure assessment of inhalation exposures resulted in classification of cleaning tasks into three major exposure groups: low, medium, and high exposures.
Low exposure category
Tasks classified in this exposure category include floor cleaning tasks. Floor cleaning generates low concentrations of VOC in the air, mainly because floor products were more diluted compared to other products. Because quaternary ammonium compounds, an important group of chemicals of concern in floor cleaning product , are not volatile chemicals, the potential for their inhalation during floor cleaning is low. Additionally, because floor cleaning does not involve product spraying, the risk of inhalation to aerosol particles is low. Despite their longer duration compared to other tasks, considering their lower exposure intensity, floor cleaning tasks can be classified in the low inhalation exposure category.
Medium exposure category
Tasks classified in this exposure category include: window and mirror cleaning, sink cleaning, counter cleaning, and toilet bowl cleaning. The potential for inhalation exposures during these tasks is higher compared to floor cleaning tasks because: a) the intensity of VOCs of concern in the air is higher due to higher concentrations of volatile ingredients in the diluted products and b) product spraying may facilitate exposures to aerosols and other non-volatile ingredients, such as quats, commonly found in products used for these tasks. Workers performing these tasks are continuously exposed to VOCs and aerosols during the workday.
High exposure category
We classified in this category “the combination tasks”, which include patient room and bathroom cleaning tasks. Due to the continuous application of many products one after another, the potential for inhalation exposures can be higher compared to when the tasks are performed separately. The shadowed boxes in Figure 1 show tasks that potentially generate higher airborne exposures. Because these tasks are done in small volume environments, it is possible that airborne VOC can increase rapidly in a short period of time exposing the worker to inhalation risks.
The other group of tasks classified in this category includes floor finishing tasks, such as stripping, waxing, and buffing. The potential for inhalation exposures from these tasks is higher compared to other tasks because: a) the airborne exposure intensity is higher due to higher VOC concentrations in the bulk product; b) they include specific activities such as the use of stripping and buffing machines, which can facilitate dust and particle re-suspension in the air that can potentially be inhaled; and c) the application of fans to speed up floor drying increases the intensity of exposures to VOC. Quantitative exposure assessment is necessary to evaluate the risk of particle inhalation during floor finishing tasks. Although less frequent overall, these tasks may contribute to high acute exposure levels that can be related to irritation mechanisms of asthma and other respiratory symptoms among cleaning workers.
Dermal exposure potential
Two examples of step by step estimations of potential skin exposures for mirror and floor cleaning are given in Additional files 4 and 5. The results of DREAM estimates for five cleaning tasks are presented in a graph given in Figure 2. This graph presents the total body potential skin exposure for five tasks along with contribution of three exposure routes emission, deposition and transfer for each task. The results of individual body part contribution to the potential total body dermal exposure/task for the five cleaning task evaluated is presented in Figure 3.