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Farm Safety Survey (FSS)

Technical Information

Data Source & Case Definitions
Data Source Sample Design Case Definitions
Farm Estimates Weighting
Data Elements
Farm Type NAGCAT Sex Age
Marital Status Second Job Large Animals Ground Fault Interrupters
Stray Voltage Stray Voltage Testing Noise Exposure Anhydrous Ammonia
Respirators Pesticides
Data Limitations
Disclaimer Limitations



Data Source

FSS data were collected through an interagency agreement between the National Institute for Occupational Safety and Health (NIOSH) and the US Department of Agriculture (USDA), National Agricultural Statistics Service (NASS). NIOSH collaborated with NASS to collect data for safety issues occurring on US operated farms.

Sample Design

The FSS was conducted using the Census of Agriculture as a sampling frame. A stratified (by geographic region) random sample of 25,000 farm households nationwide was selected for inclusion in the FSS.

FSS collected data on US farms that included information on the presence of various machinery, facilities, and practices that have been identified as potential injury hazards.

Case Definitions

Farm – any crop and/or livestock operation with $1,000 or more of gross agricultural production within a calendar year.


Farm Estimates

FSS is designed to produce national estimates of the number of farms with various types of machinery, animals, grain storage facilities, and other potential injury exposures.


Sampling weights were calculated based on the total number of farms responding by geographical region and the number of farms reported by NASS in the appropriate calendar year for each region. The nine geographical regions used are those defined by the US Bureau of the Census. Weights were then adjusted based on three farm “value of sales” categories (< $10,000, $10,000 – $99,999, ≥$100,000). All estimates were obtained using the SAS SurveyMeans procedure for a stratified equal probability sample.


Farm Type

The type of production indicated for the respondent which represents the largest proportion of gross income for the farm operation.


NAGCAT is an acronym for the North American Guidelines for Children’s Agricultural Tasks. NAGCAT is a resource developed to assist parents in assigning farm jobs to their children. The FSS question regarding NAGCAT was only asked of farm operators who reported youth under 20 years of age living in the farm household.


The distinction between male and female.


Farm operator age, in years, on the farm operator’s last birthday. Age groups in the FSS results are inclusive of the years listed in the range.

Marital Status

Self-reported marital status of the farm operator.

Second Job

Self-report of the farm operator having a job, in addition to farming, to supplement the household income. In the FSS results, days working off the farm are inclusive of the days listed in the range, and are reported for the previous 12 months.

Large Animals

Self-report of large animals kept on the farm in the previous 12 months. Large animals include cattle, bison, horses, donkeys, ponies, mules, and hogs.

Ground Fault Interrupter

A ground fault interrupter is an electrical device designed to disconnect the circuit if there is a leakage current. By detecting small leakage currents (typically 5–30 milliamperes) and disconnecting quickly enough (<30 ms), ground fault interrupters may prevent electrocution.

Stray Voltage

Stray voltage is voltage resulting from the normal delivery and/or use of electricity (usually smaller than 10 volts) that may be present when two conductive surfaces are simultaneously contacted by humans and/or animals. In the case of milking facilities, a stray electrical current passing through a cow’s body may cause reduced milk production and health problems. The stray electrical current can be caused by poor or faulty wiring, faulty equipment, improper grounding, or it can originate off the farm and be introduced through the grounded neutral wiring network.

Stray Voltage Testing

Stray voltage can be identified with an AC Voltmeter. Contact a professional electrician if you need assistance testing for stray voltage.

Noise Exposure

Noise levels are considered loud when you have to shout to be heard by someone who is three feet or less away from you.

Anhydrous Ammonia

Anhydrous ammonia is a liquid nitrogen fertilizer commonly used on farms due to its relative ease of application. Farm operators were asked if they had handled or applied anhydrous ammonia in the previous 12 months.


A respirator is a device designed to protect the wearer from inhaling harmful dusts, fumes, vapors, or gases. Respirators range from inexpensive, single-use, disposable dust masks to reusable models with replaceable cartridges. Farm operators were asked about respirator usage in the previous 12 months. All respirators for work purposes are certified by the National Institute for Occupational Safety and Health, and are clearly marked with this certification on the respirator packaging.


Pesticides include insecticides, herbicides, fungicides, rodenticides, and fumigants. Farm operators were asked if they personally handled, mixed, or applied pesticides in the previous 12 months.



Although NIOSH extends considerable effort to insure reasonable data quality for FSS estimates, there are no warranties expressed or implied with these data. The objective of FSS is to provide public access to agricultural safety and health data for US farms for use in farm safety and injury prevention activities where quantifiable measures of potential injury exposures on farms are important. Use of these data for other purposes should be done with caution.


There are some limitations to the estimates derived from FSS. First, it is not possible to verify the accuracy or completeness of the responses provided by individual farm operators, which could impart measurement error into the overall results. A second limitation is the possibility of a non-response bias. Due to the survey design, it was not possible to make a second contact to farm operators who refused to participate in the survey. This did not allow for a followback questionnaire to assess these refusals.