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Occupational Requirements Survey

Strength levels 

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The Occupational Requirements Survey (ORS) publishes job-related information on physical demands; environmental conditions; education, training, and experience; as well as cognitive and mental requirements. The job requirements reflect those necessary for workers to perform critical tasks in support of the critical job functions, and not the capabilities of individual workers. Strength estimates are physical demand requirements.

The ORS publishes five strength levels (sedentary, light, medium, heavy, and very heavy), which are based on the job requirements for performing physical demands within specific weight classes and the associated duration. (See Chart A.)

strength_chartA

 

Chart A data table
Chart A. Percentage of civilian workers by strength level, 2020
Sedentary Light Medium Heavy Very heavy

Civilian workers

27.4% 33.4% 28.4% 9.4% 1.3%

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

 

Strength levels are calculated from the weight and duration associated with lifting, carrying, and in some cases, standing.[1]

A duration chart is used to calculate the amount of time spent lifting or carrying. There are four categories of time in relation to a job's workday schedule: seldom (up to 2 percent), occasional (2 percent to 1/3), frequent (1/3 to 2/3), and constant (2/3 or more). “Negligible weight” includes anything lifted or carried weighing less than one pound.

For example, if workers deliver items weighing between 26-50 pounds occasionally, then the job would be classified as a medium strength level. However, if they delivered slightly heavier items (51-100 pounds) or the duration of carrying or lifting 26-50 pounds increased to being performed frequently, then the job would be classified as a heavy strength level. (See Table 1.) Special cases for calculating strength are used when requirements are unable to be determined, and are recorded as “unknown”.[2] (See Table 2.)

Table 1. Determining strength level based on duration of lifting or carrying
Strength level Duration of lifting or carrying
Seldom Occasionally Frequently Constantly

Light work

11-25 pounds 11-25 pounds 1-10 pounds Negligible weight

Medium work

26-50 pounds 26-50 pounds 11-25 pounds 1-10 pounds

Heavy work

51-100 pounds 51-100 pounds 26-50 pounds 11-25 pounds

Very heavy work

>100 pounds >100 pounds >50 pounds >25 pounds

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey.

 

Table 2. Special cases for calculating strength level
Strength level Description

Unknown

If it is unknown how often lifting or carrying occur or none of the conditions in table 1 are met and standing or sitting are unknown. The estimate is treated as item nonresponse.

Sedentary

If none of the conditions in the strength level chart are met and standing or walking occurs less than or equal to 1/3 of the workday.

Light work

If none of the conditions in the strength chart are met and does not meet the special conditions for unknown or sedentary.

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey.

 

Sedentary strength level

Strength is considered sedentary when none of the conditions in the strength chart are met and standing is less than or equal to 1/3 of the work schedule or workday (See Tables 1 and 2).

Occupations with critical tasks where workers typically spend the day sitting and occasionally lift items of little weight, like a pen or a few pieces of paper, require sedentary strength. (See Table 3.)

Table 3. Percentage of civilian workers with a sedentary strength level by occupation, 2020
Occupation Estimate Standard Error

Financial and investment analysts

99.2 [1]

Bill and account collectors

98.4 1.0

Public safety telecommunicators

95.7 1.1

Billing and posting clerks

95.0 2.9

Budget analysts

91.2 6.4

Bookkeeping, accounting, and auditing clerks

90.9 1.3

Purchasing managers

89.2 4.4

Medical secretaries and administrative assistants

89.0 2.6

Computer and information systems managers

88.3 49.0

Human resources specialists

88.2 2.1

Dispatchers, except police, fire, and ambulance

87.7 3.4

Graphic designers

75.9 9.6

Bus drivers, school

69.7 10.8

Medical records specialists

68.9 7.3

Social and community service managers

64.9 9.8

[1] Standard error is less than 0.5.

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

 

Light strength level

If the work level of an occupation does not meet the conditions for the other strength levels, including sedentary, and it is not unknown, a light strength level is required.[3] (See Tables 1 and 2.) Examples of occupations with light strength level requirements include:

  • Hosts and hostesses (96.8 percent light strength required) may do activities such as carrying menus and raising and lowering pagers for customers in a queue for 2/3 or more of the workday.

  • News analysts, reporters, and journalists (74.7 percent light strength required) may carry a laptop for 1/3 to 2/3 of the workday.

Table 4. Percentage of civilian workers with a light strength level by occupation, 2020
Occupation Estimate Standard Error

Hairdressers, hairstylists, and cosmetologists

97.1 3.0

Hosts and hostesses, restaurant, lounge, and coffee shop

96.8 1.3

Hotel, motel, and resort desk clerks

80.8 8.8

Waiters and waitresses

77.0 5.2

Maids and housekeeping cleaners

76.0 3.7

Music directors and composers

75.7 14.9

News analysts, reporters, and journalists

74.7 3.7

Dental assistants

72.6 6.5

Gambling cage workers

68.8 11.6

Coaches and scouts

66.6 11.7

Bartenders

66.2 8.7

Occupational health and safety specialists

59.7 7.9

Counter and rental clerks

57.9 9.5

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

 

Medium strength level

For civilian workers, 28.4 percent of workers were required to work at a medium strength level. Examples of occupations with medium strength level requirements include:

  • Animal caretakers may lift 30 pound bags of grain to feed horses at the racetrack for up to 2 percent of the workday.

  • Chefs and head cooks may carry a 2 pound tray of cooking supplies to prepare dinner meals for 2/3 or more of the workday.

Table 5. Percentage of civilian workers with a medium strength level by occupation, 2020
Occupation Estimate Standard error

Animal caretakers

85.4 9.5

Landscaping and groundskeeping workers

67.3 7.1

Chefs and head cooks

65.7 8.6

Nursing assistants

59.2 4.5

Licensed practical and licensed vocational nurses

55.4 5.3

Preschool teachers, except special education

52.5 10.0

Physical therapists

52.1 10.7

Dishwashers

48.9 4.8

Construction laborers

48.6 6.5

Fast food and counter workers

45.9 5.9

Personal care aides

43.5 4.1

Bartenders

31.6 8.4

Waiters and waitresses

22.2 6.1

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

 

Heavy strength level

For civilian workers, 9.4 percent of workers were required to work at a heavy strength level. Examples of occupations with heavy strength level requirements include:

  • Construction laborers at a building site may wear a 30 pound tool belt from 1/3 to 2/3 of the workday.

  • Firefighters might lift a 15 pound hose for 2/3 or more of the workday.

Estimates ranged from 6.0 percent for first-line supervisors of food preparation and serving workers to 59.2 percent of heating, air conditioning, and refrigeration mechanics and installers.

Table 6. Percentage of civilian workers with a heavy strength level by occupation, 2020
Occupation Estimate Standard Error

Heating, air conditioning, and refrigeration mechanics and installers

59.2 14.1

Bus and truck mechanics and diesel engine specialists

48.1 8.1

Construction laborers

46.4 6.8

Highway maintenance workers

44.4 11.1

Carpenters

41.1 9.7

Plumbers, pipefitters, and steamfitters

35.1 11.3

Shipping, receiving, and inventory clerks

31.3 6.1

Nursing assistants

30.9 5.5

Physical therapists

23.4 7.4

Personal care aides

17.5 3.2

Landscaping and groundskeeping workers

14.8 6.5

Cooks, restaurant

9.9 1.3

First-line supervisors of construction trades and extraction workers

8.8 1.8

First-line supervisors of food preparation and serving workers

6.0 0.7

Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

 

Very heavy strength level

For civilian workers, 1.3 percent required a very heavy strength level, which indicates requirements beyond the conditions set for heavy work.

Very heavy work was required for 2.7 percent of workers in construction and extraction occupations. Lifting items that weigh 50 pounds or more, like bags of cement or sheets of plywood, for more than 1/3 of the workday would be considered very heavy work. A very heavy work strength level was required for 2.0 percent of healthcare support occupations. Lifting patients to and from their beds for 10 minutes during an 8-hour shift would fall within very heavy work. Very heavy work was required for 1.9 percent of transportation and material moving occupations and 0.5 percent of production occupations.

 

Additional resources:

Articles:

 

For additional information on occupational requirements see the ORS homepage or download the ORS complete dataset to explore the latest estimates.

 


[1] See the sitting and standing factsheet for more information on these requirements.

[2] In instances where field economists are unable to determine certain job requirements from the respondent, they record these data as "unknown" and strength level is derived through imputation. See the Handbook of Methods for more information.

[3] For more information on work levels, see National Compensation Survey: Guide for Evaluating Your Firm's Jobs and Pay and the Calculation section of the Handbook of Methods.