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, 30.3 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, 2025
Occupation	Estimate	Standard error
Compensation, benefits, and job analysis specialists	>99.5	^[1]
Financial and investment analysts	>99.5	^[1]
Software developers	>99.5	^[1]
Switchboard operators, including answering service	>99.5	^[1]
Billing and posting clerks	99.2	0.7
Management analysts	99.1	0.9
Payroll and timekeeping clerks	99.1	0.5
Accountants and auditors	99.0	<0.5
Bookkeeping, accounting, and auditing clerks	98.2	0.6
Public safety telecommunicators	97.6	1.8
Bill and account collectors	97.5	1.5
Administrative services managers	97.0	2.1
Computer systems analysts	96.6	2.0
Loan interviewers and clerks	96.2	4.2
Human resources managers	96.0	1.5
^[1] The standard error is not available for this estimate. Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey 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, 33.7 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, 2025
Occupation	Estimate	Standard error
Hosts and hostesses, restaurant, lounge, and coffee shop	96.9	1.9
Middle school teachers, except special and career/technical education	96.6	1.5
Physician assistants	95.4	2.8
Opticians, dispensing	94.4	5.7
Elementary school teachers, except special education	92.1	2.1
Secondary school teachers, except special and career/technical education	90.0	2.8
Phlebotomists	88.5	4.3
Kindergarten teachers, except special education	87.8	5.8
Library assistants, clerical	85.3	5.9
Hotel, motel, and resort desk clerks	84.0	2.3
Laundry and dry-cleaning workers	83.0	3.3
Substitute teachers, short-term	80.5	9.0
Dental assistants	78.5	2.2
Special education teachers, elementary school	78.4	3.6
Waiters and waitresses	77.7	3.9
^[1] The standard error is not available for this estimate. Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

Medium strength level

For civilian workers, 29.1 percent of workers were required to work at a medium strength level. Examples of occupations with medium strength level requirements include:

Veterinary assistants and laboratory animal caretakers may lift 30 pound dog food bags for up to 2 percent of the workday.

Table 4. Percentage of civilian workers with a medium strength level by occupation, 2025
Occupation	Estimate	Standard error
Veterinary assistants and laboratory animal caretakers	87.3	5.7
Merchandise displayers and window trimmers	87.0	3.6
Helpers–electricians	86.8	6.5
Water and wastewater treatment plant and system operators	84.5	9.1
Automotive service technicians and mechanics	80.2	5.1
Baggage porters and bellhops	79.3	9.3
Helpers–production workers	75.3	9.3
Stockers and order fillers	74.9	3.5
Audio and video technicians	74.5	8.4
Industrial machinery mechanics	74.5	7.8
Veterinary technologists and technicians	74.3	6.8
Maintenance workers, machinery	72.9	7.0
Construction laborers	70.8	7.0
Landscaping and groundskeeping workers	70.5	6.5
Refuse and recyclable material collectors	70.3	9.1
^[1] The standard error is not available for this estimate. Source: U.S. Bureau of Labor Statistics, Occupational Requirements Survey

Heavy strength level

For civilian workers, 6.2 percent of workers were required to work at a heavy strength level. Examples of occupations with heavy strength level requirements include:

Aircraft mechanics and service technicians might occasionally lift parts weighing over 50 pounds.

Table 5. Percentage of civilian workers with a heavy strength level by occupation, 2025
Occupation	Estimate	Standard error
Butchers and meat cutters	68.5	6.6
Reservation and transportation ticket agents and travel clerks	60.8	4.7
Highway maintenance workers	52.1	6.6
Aircraft mechanics and service technicians	49.8	10.4
Tire repairers and changers	43.5	12.1
Operating engineers and other construction equipment operators	41.9	12.9
Correctional officers and jailers	37.4	6.9
Police and sheriff’s patrol officers	34.5	3.9
First-line supervisors of fire fighting and prevention workers	33.3	11.2
Firefighters	30.3	6.1
Plumbers, pipefitters, and steamfitters	29.9	7.0
Physical therapist assistants	28.5	6.8
Lifeguards, ski patrol, and other recreational protective service workers	25.8	7.9
Laborers and freight, stock, and material movers, hand	25.2	5.0
Helpers–production workers	<25	^[1]
^[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, 0.7 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.

Table 6. Percentage of civilian workers with a very heavy strength level by occupational group, 2025
Occupation	Estimate	Standard error
Protective service occupations	14.9	2.4
Construction and extraction occupations	1.5	0.5
Healthcare practitioners and technical occupations	1.0	0.5
Installation, maintenance, and repair occupations	0.8	<0.5
Transportation and material moving occupations	0.8	<0.5
^[1] The standard error is not available for this estimate. 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.