Job-exposure and Job task-exposure matrices to evaluate exposure
to disinfectants in U.S. nurses

A job-exposure matrix (JEM) and a job task-exposure matrix (JTEM) have been designed to evaluate occupational exposure to specific disinfectants for several nursing jobs.

Design of the JEM and JTEM:

Disinfectant use was assessed by an occupational questionnaire in 9073 US female registered nurses without asthma, who were drawn from the Nurses’ Health Study II ( This study is based at the Channing Division of Network Medicine, at Brigham and Women’s Hospital in Boston, MA.

The JEM was created based on self-reported frequency of use (1–3, 4–7 days/week) of 7 disinfectants (alcohol, hypochlorite bleach, peroxide bleach, glutaraldehyde, quats, enzymatic cleaners, formaldehyde) and sprays in 8 nursing jobs (emergency room, operating room, intensive care unit, other inpatient nurse, outpatient or community, other hospital nursing, nursing outside hospital and nursing education or administration). The JTEM was designed by combining nursing jobs and disinfection tasks (cleaning surfaces only, cleaning at least instruments, none).

For both JEM and JTEM, exposure was evaluated in 3 classes (low, medium, high) using product-specific cut-offs defined from the distribution of self-reported exposure per job/task.


Quinot C, Dumas O, Henneberger PK, Varraso R, Wiley AS, Speizer FE, Goldberg M, Zock JP, Camargo CA Jr, Le Moual N. Development of a Job-Task-Exposure Matrix to assess occupational exposure to disinfectants among U.S. nurses. Occup Environ Med 2017;74:130-7.

How to access the JEM and JTEM: Both are available freely by contacting Nicole Le Moual (

Funding: This work was funded by Centers for Disease Control and Prevention grant R01 OH-10359 (Camargo).

Frequently Asked Questions:

1. What does this tool do?

The job-exposure matrix (JEM) and job-task-exposure matrix (JTEM) were developed to evaluate occupational exposure to specific disinfectants to nursing jobs, according to the type of job (JEM) and task performed (JTEM).

2. What is included in the matrices?

The JEM / JTEM are two dimensional matrices with 7 disinfectants and sprays on one axis (columns) and nursing jobs / nursing job & tasks on the other axis (rows).

The job axis of the JEM contains 8 nursing jobs (see above).

The job-task axis of the JTEM contains 24 categories combining jobs (8 categories, see above) and tasks performed weekly (3 categories: cleaning surfaces only, cleaning at least instruments, no cleaning task).

The exposure axis of the JEM and JTEM contains 7 disinfectants and sprays.

3. How were the exposure categories chosen?

Hospital workers, and particularly nurses, are highly exposed to disinfecting products both in frequency and intensity. Disinfecting products are complex mixtures of many chemical components, some of which may cause or exacerbate asthma. Ammonia, bleach, glutaraldehyde, ortho-phthalaldehyde or quaternary ammonium compounds (quats) are common chemicals found in cleaning products or disinfectants. Occupational exposure may be heterogeneous in a given occupation according to the tasks performed.

4. What criteria were used to classify a job/task as exposed for each category?

The JEM and JTEM were designed using data from the Nurses’ Health Study II. Data on frequency of use of disinfectants (“On how many days per week do you use the following disinfectants at work?”), disinfection tasks performed (“On how many days per week, on average, do you clean medical instruments/surfaces at work with disinfectants?”), and current nursing job (“Which best describes your current employment status?”) were collected in a specific occupational questionnaire.

Cut-offs were defined to classify exposure in ‘low’, ‘medium’ and ‘high’ levels for each disinfectant. Cuts-offs were chosen according to the distribution of the exposure prevalence in the nurse participants. The first quartile (Q1) and median were used to define cut-offs for low and high exposure, respectively.