Bureau of Labor Statistics > Occupational Requirements Survey > Publications > Factsheets

Strength levels

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.

The ORS publishes five strength levels (sedentary, light, medium, heavy, and very heavy), which are part of the published physical demands, and are calculated from the weight and duration associated with lifting, carrying, and in some cases, standing.[1]

Chart A. Percentage of civilian workers by strength level

Duration levels are used to calculate the amount of time spent lifting or carrying. There are four duration levels 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).

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. “Negligible weight” includes anything lifted or carried weighing less than one pound. (See Table 1.)

Table 1. Determining strength level based on lifting or carrying duration or percentage of the workday spent standing
Strength level	Duration of lifting or carrying				Percent of workday standing^[1]
Strength level	Seldom	Occasionally	Frequently	Constantly	Percent of workday standing^[1]
Sedentary work	Up to 10 pounds	Up to 10 pounds	Negligible weight^[2]	No weight	Less than or equal to 1/3^[3]
Light work	11–25 pounds	11–25 pounds	1–10 pounds	Negligible weight^[2]
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
^[1] Standing estimates includes time spent standing, walking, and in low postures. ^[2] Negligible weight includes anything lifted or carried weighing less than 1 pound. ^[3] When the sedentary lifting or carrying requirements are met, and more than 1/3 of the workday is spent standing, light work is required. Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey.

Sedentary strength level

Strength is considered sedentary when none of the light strength requirements are met and standing is required less than or equal to 1/3 of the work schedule or workday.

For civilian workers, 29.3 percent of workers were required to work at a sedentary strength level. 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 2.)

Table 2. Percentage of civilian workers with a sedentary strength level by occupation, 2023
Occupation	Estimate	Standard error
Aerospace engineers	>99.5	^[1]
Software quality assurance analysts and testers	>99.5	^[1]
Word processors and typists	>99.5	^[1]
Architectural and civil drafters	99.5	<0.5
Software developers	99.0	<0.5
Financial and investment analysts	98.5	<0.5
Web and digital interface designers	98.1	0.8
Bill and account collectors	97.6	1.1
Proofreaders and copy markers	96.6	3.2
Public safety telecommunicators	96.6	1.3
Budget analysts	96.5	2.6
Computer programmers	96.5	1.1
Insurance sales agents	96.4	2.0
^[1] The standard error is not available for this estimate. 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, a light strength level is required. For civilian workers, 32.9 percent of workers were required to work at a light strength level. Examples of occupations with light strength level requirements include:

Hosts and hostesses 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.
Hotel, motel, and resort desk clerks might spend more than 1/3 of their workday standing.

Table 3. Percentage of civilian workers with a light strength level by occupation, 2023
Occupation	Estimate	Standard error
Barbers	99.1	0.9
Hairdressers, hairstylists, and cosmetologists	98.5	1.3
Middle school teachers, except special and career/technical education	95.3	0.9
Secondary school teachers, except special and career/technical education	91.2	0.9
Hosts and hostesses, restaurant, lounge, and coffee shop	89.9	3.6
Physics teachers, postsecondary	87.7	3.5
Gambling managers	87.4	6.1
Opticians, dispensing	86.9	8.1
Hotel, motel, and resort desk clerks	82.5	5.4
Teachers and instructors, all other	81.3	6.7
Adult basic education, adult secondary education, and english as a second language instructors	81.1	10.4
Chemists	79.2	6.1
Waiters and waitresses	78.3	2.1
Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

Medium strength level

For civilian workers, 28.6 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.
Packers and packagers, such as a grocery store bagger, could be lifting or carrying groceries weighing more than 1 pound for 2/3 or more of the workday.

Table 4. Percentage of civilian workers with a medium strength level by occupation, 2023
Occupation	Estimate	Standard error
Foundry mold and coremakers	91.2	4.6
Animal caretakers	88.4	4.8
Veterinary assistants and laboratory animal caretakers	86.1	9.8
Production workers, all other	84.5	8.3
Tapers	83.3	8.7
Multiple machine tool setters, operators, and tenders, metal and plastic	82.5	6.9
Couriers and messengers	82.4	10.4
Forging machine setters, operators, and tenders, metal and plastic	81.7	7.0
Textile cutting machine setters, operators, and tenders	80.3	8.5
Veterinary technologists and technicians	79.5	4.7
Helpers–production workers	76.5	4.7
Roofers	74.7	7.2
Magnetic resonance imaging technologists	74.5	10.4
Packers and packagers, hand	71.2	3.6
Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

Heavy strength level

For civilian workers, 8.2 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.
Bus and truck mechanics and diesel engine specialists might occasionally lift truck parts weighing over 50 pounds.

Table 5. Percentage of civilian workers with a heavy strength level by occupation, 2023
Occupation	Estimate	Standard error
Light truck drivers	64.2	4.4
Heating, air conditioning, and refrigeration mechanics and installers	52.5	6.7
Outdoor power equipment and other small engine mechanics	49.9	14.5
Occupational therapy aides	<45	^[1]
Bus and truck mechanics and diesel engine specialists	43.3	6.9
Electrical power-line installers and repairers	43.3	9.9
Control and valve installers and repairers, except mechanical door	41.8	10.0
Podiatrists	<35	^[1]
Weighers, measurers, checkers, and samplers, recordkeeping	<35	^[1]
Construction laborers	34.8	4.3
Highway maintenance workers	33.7	7.1
Industrial machinery mechanics	31.2	4.4
^[1] The standard error is not available for this estimate. Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

Very heavy strength level

For civilian workers, 1.0 percent required a very heavy strength level, which indicates requirements beyond the conditions set for heavy work. Examples of occupational groups with heavy strength level requirements include:

Laborers in construction and extraction occupations may lift items that weigh 50 pounds or more, like bags of cement or sheets of plywood, for more than 1/3 of the workday.
Workers in healthcare support occupations may lift patients to and from their beds for 10 minutes during an 8-hour shift.

Table 6. Percentage of civilian workers with a very heavy strength level by occupational group, 2023
Occupation	Estimate	Standard error
Construction and extraction occupations	1.8	<0.5
Transportation and material moving occupations	1.8	<0.5
Healthcare support occupations	1.3	<0.5
Personal care and service occupations	0.9	<0.5
Arts, design, entertainment, sports, and media occupations	0.6	<0.5
Community and social service occupations	0.5	<0.5
Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

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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.