Use Factor, Occupancy Factor, Workload

Posted on Updated on

Use Factor

If radiation, whether primary or secondary, is never directed at a particular wall or structure, then ordinary or existing construction is sufficient. Most structures in a diagnostic x-ray suite, however, are struck by radiation to some degree for some fraction of the weekly beam-on time. The use factor (U) is a quantity that was introduced to select this fractional contact time.

For primary radiation, the use factor represents the portion of beam-on time that the x-ray beam is directed at a primary barrier during the week. Consider a typical radiographic suite with a wall Bucky unit. If 50% of the x-ray examinations involve this device, the wall behind the Bucky unit has a U (primary) = 1/2 .

Because scatter and leakage radiation emerge in all directions in the x-ray room, every wall, door, viewing window, and other surface will always be struck by some quantity of radiation. Therefore U (secondary) = 1 for all radiation-accessible structures.

(Statkiewicz Sherer, Mary Alice. Radiation Protection in Medical Radiography, 6th Edition. Mosby, 032010. p. 300).

Occupancy Factor

Radiation barriers are installed to protect personnel and the general public from radiation that otherwise would reach them uninhibited. If no one will ever be present beyond an existing wall in a particular area while the x-ray unit is being operated, the addition of supplementary shielding to that wall is unnecessary. The opposite situation is an area in which someone is always present. When planning radiation protection shielding for a diagnostic x-ray suite, the designer must consider not only zero and full occupancy cases but also the more common partial occupancy situation. The occupancy factor (T) is used to modify the shielding requirement for a particular barrier by taking into account the fraction of the workweek during which the space beyond the barrier is occupied.

(Statkiewicz Sherer, Mary Alice. Radiation Protection in Medical Radiography, 6th Edition. Mosby, 032010. p. 301).


Because a diagnostic x-ray unit does not produce radiation 24 hours per day, 7 days per week, a parameter must be used to reflect the unit’s radiation-on time in the determination of barrier shielding requirements. The quantity that best describes the weekly radiation use of a diagnostic x-ray unit is called its workload (W).The workload is essentially the radiation output weighted time that the unit is actually delivering radiation during the week. Workloads are specified either in units of milliampere-seconds (mAs) per week or milliampere-minutes (mA-min) per week. The following example illustrates this concept.

(Statkiewicz Sherer, Mary Alice. Radiation Protection in Medical Radiography, 6th Edition. Mosby, 032010. p. 300).

23 thoughts on “Use Factor, Occupancy Factor, Workload

    drcahn said:
    July 31, 2015 at 3:49 am

    hey i like the content of the page and blog. Dental Clinic Stamford

    Lesley said:
    February 20, 2015 at 7:36 am

    I’d like to live on Kauai. It was small, quiet, and it had lots of opportunities for an adventure.

    investment insights said:
    August 14, 2014 at 7:45 am

    I value the blog post.Really looking forward to read more. Really Great.
    investment insights

    Cara Hamil Sehat said:
    August 9, 2014 at 7:56 am

    Appreciate you sharing, great article post.Much thanks again. Fantastic.
    agar cepat hamil

    shisha sticks said:
    August 8, 2014 at 6:24 am

    Really informative article.Thanks Again. Really Great.
    shisha sticks

    avg pc tuneup key generator said:
    August 7, 2014 at 2:21 pm

    Enjoyed every bit of your post.Really looking forward to read more. Want more.
    Avg Pc tuneup 2014 Product Key

    serrurier parisien said:
    August 7, 2014 at 7:22 am

    A round of applause for your blog. Will read on…
    serrurier parisien

    concert tickets 2011 said:
    August 7, 2014 at 2:15 am

    We are will no longer accepting comments on this
    article concert tickets 2011 with a vast expertise in online payday cash advances, this site
    is suited in order to meet all your requirements
    if it relates to procuring cash between paydays.

    adult toys said:
    August 5, 2014 at 7:00 am

    Im thankful for the blog.Really thank you! Fantastic.
    adult toys

    cosmetic dentist san diego said:
    August 4, 2014 at 3:49 am

    Awesome blog. Will read on…
    cosmetic dentist san diego

    cosmetic dentist san diego said:
    August 4, 2014 at 3:35 am

    A round of applause for your blog article.Much thanks again. Great.
    dentures san diego

    DUI Lawyer San Francisco said:
    August 1, 2014 at 11:51 am

    Thank you for your blog post.Much thanks again. Really Cool.
    DUI Lawyer San Francisco

    best tablet for the money said:
    July 30, 2014 at 5:06 am

    Thanks so much for the blog.
    best 10 inch tablet

    best tablet for the money said:
    July 30, 2014 at 4:57 am

    I really like and appreciate your blog.Thanks Again. Really Cool.
    tablet deals

    Yahoo said:
    July 25, 2014 at 6:39 am

    Hey mate ! I just saw your website and all I can say is that is very nice.
    Lots of beneficial information on it. I also see that you
    don’t rank very high in Google. You are able
    to achieve better rankings building back links for your back links using a high page rank blog network.
    This specific service will take your website higher in the search engines – -.
    If you need any help with this plugin send me an E-mail. said:
    July 18, 2014 at 10:53 am

    concord 11s jordan 11 infrared low concord 11s gamma blue 11 restock jordan 11 low top concord jordan 11 concord for saleconcord 11s restockcheap jordan 11 bredcolumbia 11s for salejordan 11 aqua for sale[url=][b]cheap legend blue 11s[/b][/url][url=][b]low 11s[/b][/url][url=][b]cheap legend blue 11s[/b][/url][url=][b]gamma blue 11[/b][/url][url=][b]jordan 11 legend blue[/b][/url]jordan 4 bred for sale cheap bred 4s cheap toro bravo 4s jordan 4 fear green glow 4s for salejordan 4 green glow for salejordan 4 green glowcheap toro bravo 4s[url=][b]jordan 4 toro bravo[/b][/url][url=][b]fear 4s for sale[/b][/url][url=][b]green glow 4s for sale[/b][/url][url=][b]jordan 4 toro bravo[/b][/url]jordan 5 fire red for sale oreo 5s for sale jordan 5 fire red bel air 5s for sale jordan 5 oreo restockcheap bel air 5scheap jordan 5 3lab5bel air 5s restock[url=][b]cheap fire red 5s[/b][/url][url=][b]jordan 5 oreo for sale[/b][/url][url=][b]cheap bel air 5s[/b][/url][url=][b]jordan 3lab5 restock[/b][/url]

    fiverrr23Jz said:
    June 25, 2014 at 8:53 pm

    Im thankful for the blog post.Much thanks again. Much obliged.

    buy instagram followers said:
    June 24, 2014 at 2:02 pm

    I’m not sure where you’re getting your info, but great topic.
    I needs to spend some time learning more or understanding more.
    Thanks for excellent info I was looking for this info
    for my mission.

    Ftions said:
    May 11, 2014 at 12:52 pm

    Thank you for your article.Really thank you! Much obliged.

    GINA said:
    March 25, 2014 at 5:43 pm

    Hi, i have reading out and i will definitely bookmarrk your site, just wanted to say i liked this article.

    JOSEPH said:
    March 10, 2014 at 10:05 pm

    I do believe all the ideas you have offered in your post. They are very convincing and can certainly work. Still, the posts are very short for novices. May just you please prolong them a bit from next time? Thank you for the post

    Garry Delmastro said:
    February 12, 2014 at 8:12 pm

    excellent app many thanks for sharing

    SEO Services Firm said:
    November 25, 2011 at 12:34 pm

    This is a message to the website owner. Does your website get very little visitors or not rank for search terms with Google? Well we can help! We can provide you with tens of thousands of backlinks to your site! This will help your rankings on Google and make your website more visible to your target audience. Take a look as I am sure you will be interested.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s