ALARA examples fall into three categories—time, distance, and shielding. Common examples include using pulsed fluoroscopy to cut beam-on time, stepping back to leverage the inverse-square law, and wearing lead aprons and thyroid collars.
If you’re a Radiation Safety Officer or Director of Radiology, or work closely with one, you’ve probably cited ALARA standards countless times across training sessions, policy documentation, and audits. Consistent ALARA application is one of the most important Radiation Safety Officer responsibilities and a matter of both regulatory compliance and staff safety.
But for new fluoroscopy techs who haven’t seen ALARA in practice, there’s a big difference between knowing what ALARA stands for and knowing how to ensure its consistent application. This article will introduce some ALARA examples to clarify exactly what time, distance, and shielding examples look like in practice and how to make sure your facility is ALARA compliant.
What Does ALARA Actually Mean in a Clinical Setting?
ALARA, or As Low As Reasonably Achievable, is a radiation safety framework for occupational radiation exposure reduction. It applies to healthcare facilities that work with ionizing radiation, defining an approach that addresses exposure duration and distance, as well as the use of shielding.
The underlying framework of the ALARA principle in radiology requires facilities to minimize the duration of staff exposure, increase the physical distance between staff and ionizing radiation sources, and use effective shielding methods. For a fuller breakdown of how these standards translate to the bedside, see how ALARA is applied in hospitals.
From the frontline worker’s perspective, ALARA compliance in healthcare effectively reduces the cumulative dose of radiation received over the course of their career. Over the long term, this reduces their chances of radiation-related cancer and other radiation health effects.
ALARA Time Examples: Minimizing Exposure Duration
Time and distance are relatively straightforward to put into practice as they are matters of being intentional about one’s behavior by minimizing beam-on time and maximizing the physical separation between radiology personnel and ionizing radiation sources.
Minimizing Beam-On Time
Since it’s one of the highest-exposure procedures in hospital settings, most ALARA fluoroscopy examples focus on reducing beam-on time.
Three Examples
- Pulsed fluoroscopy reduces the radiation dose by 50-85% compared to a continuous beam, depending on the pulse rate. When it’s appropriate, fluoroscopy operators can use this setting. Radiology techs can confirm patient positioning before initiating exposure to reduce the likelihood of repeat imaging.
- Staff should never linger near a C-arm during or after activation, complete tasks in high-radiation zones efficiently, and exit as soon as possible.
- Use last-image-hold (LIH) to review the most recent fluoroscopic frame on-screen instead of re-activating the beam, eliminating unnecessary seconds of exposure.
- Exit the room, or step out of the primary and scatter field, whenever your presence is not required for the exposure.
- Plan efficient patient and equipment positioning before activation so each beam-on interval is as short as possible and repeat imaging is minimized.
ALARA Distance Examples: Using the Inverse Square Law
Distance as a Daily Practice
As the inverse square law quantifies (see below), the scatter radiation gradient is steep. The further away from an ionizing radiation source, the better.
Three Examples
- Non-essential personnel should step behind lead barriers or into adjacent rooms during imaging procedures.
- Surgeons and techs can use extension handles or remote controls where workflows permit.
- Keep all non-essential staff at least six feet from the radiation source during active exposure.
How Does the Inverse Square Law Apply to Daily Radiology Work?
As it applies to daily radiology work, the math behind the inverse square law is fairly straightforward. It states that when someone doubles their distance from a radiation source, they reduce their dose by a factor of four. Put another way, doubling the distance means reducing the dose by 75%.
Picture two colleagues working in an interventional suite: one standing two feet away from the radiation source and the other standing eight feet away. In this example, the colleague two feet from the source receives around sixteen times the dose of the colleague who’s eight feet away.
When you consider the fact that radiation dose is cumulative, it becomes especially clear how the application of ALARA standards for time and distance can matter so much over the lifetime of someone who works with ionizing radiation.
ALARA Shielding Examples: Aprons, Collars, Glasses & Barriers
The third component of ALARA compliance is the use of effective shielding measures. This includes two key forms of shielding. First, it includes the use of physical and environmental controls, such as rooms or walls constructed with specialized shielding. The other shielding aspect of ALARA is radiation protection PPE like lead aprons, thyroid collars, and protective eyewear.
But these measures are only effective if they are well-maintained and regularly inspected to ensure they are intact and fit for use. Consider lead aprons and thyroid shields, for example. When well-fitted and properly maintained, they can reduce scatter radiation exposure by 90-95%, depending on the energy of the radiation and the thickness of the PPE.
Beyond the apron, a complete shielding kit layers several barriers between staff and scatter radiation:
- Thyroid collars: wrap the neck to protect the highly radiosensitive thyroid gland, which is often left exposed above the apron line.
- Leaded glasses: reduce dose to the lens of the eye, a tissue vulnerable to radiation-induced cataracts during long interventional cases.
- Mobile radiation shields and barriers: freestanding or ceiling-suspended shields that intercept scatter close to the source before it reaches staff.
- Table drapes: disposable or reusable leaded drapes attached at the table edge that block under-table scatter directed at the operator’s lower body.
What Makes a Lead Apron Compliant With ALARA Standards?
Lead apron ALARA compliance means it meets the threshold of keeping radiation exposure “As Low As Reasonably Achievable,” based on its fit, radiation attenuation, and structural integrity with no defects.
Most research states that an effective thickness for lead aprons is between 0.25-0.5 mm of lead equivalence. They should have zero internal defects and undergo annual radiographic (X-ray) inspections, with all inspection results documented.
What ALARA Documentation Is Required, and Who Is Responsible?
Radiation Safety Officers, or whoever is managing the radiation safety program at your facility, are required to maintain organized records that demonstrate active, ongoing compliance with the ALARA standard. Specific documentation requirements under the Joint Commission include:
- Annual lead apron inspection results tied to individual asset IDs
- Scan dates, defect findings, and disposition records (repaired, retired, returned to service)
Engineering vs. Administrative Controls in ALARA
ALARA is reinforced by two layers of program controls beyond individual behavior. Engineering controls are built into the equipment and environment—collimation to restrict the beam to the area of interest, added beam filtration, last-image-hold, and digital or pulsed imaging that lowers dose per study. Administrative controls are the policies and oversight that govern how people work: dosimetry badge monitoring, staff training, rotating personnel through high-exposure tasks, and enforcing occupational dose limits. Together they ensure that dose reduction does not rely on any single person remembering to do the right thing.
ALARA Examples at a Glance
| Principle | Example | How It Lowers Dose |
|---|---|---|
| Time | Pulsed / low-frame-rate fluoroscopy | Cuts beam-on time (about 50–85% less dose than continuous) |
| Time | Last-image-hold; exit the room when not needed | Fewer seconds of exposure |
| Distance | Step back; use extension tongs or remote controls | Inverse-square law: 2x distance ≈ 1/4 the dose |
| Distance | Keep ~6 ft from the source during exposure | Sharp dose falloff with distance |
| Shielding | Lead apron (0.25–0.5 mm Pb-equivalent) | Blocks ~90–95% of scatter to the torso |
| Shielding | Thyroid collar | Protects the radiosensitive thyroid |
| Shielding | Leaded glasses | Reduces lens/eye dose |
| Shielding | Mobile shields, barriers, table drapes | Block scatter at the source |
How Can Healthcare Facilities Build a More Complete ALARA Program?
A complete ALARA-compliant program includes all three elements of the ALARA framework: time, distance, and shielding. That means building time and distance protocol into training and daily workflows, and managing shielding integrity as a recurring, documented process.
Garment lifecycle management is an important aspect of ALARA compliance. As the first company to offer comprehensive radiation protection equipment lifecycle services, RadCare Services (RCS) helps hospitals implement audit-ready, ALARA-compliant safety programs. Services include deep cleaning and disinfection, annual X-ray integrity scanning, complimentary repairs, and digital asset tracking through RadComply®.
Contact RadCare Services today to simplify garment lifecycle management and ensure your facility’s ALARA compliance, so your clinical staff can focus on patient care.
Frequently Asked Questions
What are the three ALARA principles?
Time, distance, and shielding.
What is an example of the time principle?
Using pulsed fluoroscopy to reduce beam-on time.
How does distance reduce radiation dose?
By the inverse-square law—doubling your distance cuts dose to about one-quarter.
How much do lead aprons reduce exposure?
A 0.25–0.5 mm lead-equivalent apron blocks roughly 90–95% of scatter to the torso.
What is an example of shielding besides aprons?
Thyroid collars, leaded glasses, and mobile barriers or table drapes.
