Coding Ahead
CasePilot
Medical Coding Assistant
Case2Code
Search and Code Lookup Tool
CareerCenter
Medical Coding Job Board
Log in Register free account

Need help choosing the right code?

Ask CasePilot about procedures, modifiers, bundling, and coding guidance.

Try CasePilot

Official Description

Silica

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 84285 refers to a laboratory test specifically designed to measure the levels of silica in the blood or urine. Silica, a mineral commonly found in the environment, is typically present in the body in a bound form, associated with proteins and lipids. It plays a crucial role in the structure of collagen, which is essential for maintaining the elasticity of the skin and the strength of bones. Elevated levels of silica can indicate various health issues, particularly those related to occupational exposure to inhaled silica particles. Such exposure is often linked to conditions like silicosis, lung cancer, pulmonary tuberculosis, chronic airway diseases, autoimmune disorders, and chronic renal failure. The testing process involves obtaining a blood sample through a procedure known as venipuncture, which is separately reportable. For urine testing, a sample is collected from a random void. The analysis of serum or plasma is conducted using quantitative inductively coupled plasma/atomic emission spectrometry, while urine samples are analyzed using quantitative inductively coupled plasma/optical emission spectrometry. It is important to note that the use of gadolinium contrast media within 48 hours prior to urine sample collection may interfere with the test results, potentially leading to inaccurate measurements of silica levels.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The silica test (CPT® Code 84285) is indicated for the evaluation of silica exposure and its potential health effects. The following conditions and symptoms may warrant this test:

  • Occupational Exposure: Individuals who have been exposed to silica dust in occupational settings, such as mining, construction, or manufacturing, may require testing to assess silica levels in the body.
  • Silicosis: Patients presenting with respiratory symptoms or a history of silica exposure may be tested for silica to confirm a diagnosis of silicosis, a lung disease caused by inhaling silica dust.
  • Lung Cancer: Individuals with a history of silica exposure and presenting symptoms suggestive of lung cancer may undergo this test as part of their diagnostic workup.
  • Pulmonary Tuberculosis: Testing may be indicated in patients with pulmonary tuberculosis who have a history of silica exposure, as silica can exacerbate respiratory conditions.
  • Chronic Airway Diseases: Patients with chronic respiratory conditions may be tested to evaluate the impact of silica exposure on their health.
  • Autoimmune Disorders: Individuals with autoimmune disorders may be tested for silica levels, as exposure can influence the severity of these conditions.
  • Chronic Renal Failure: Testing may be indicated in patients with chronic renal failure to assess potential silica accumulation and its effects on kidney function.

2. Procedure

The procedure for testing silica levels involves several key steps, which are outlined below:

  • Step 1: Sample Collection - Blood: A blood sample is obtained through a procedure known as venipuncture. This involves inserting a needle into a vein, typically in the arm, to draw blood. The blood sample is then collected in a sterile container for further analysis.
  • Step 2: Sample Collection - Urine: A urine sample is collected from a random void. This means that the patient is asked to provide a urine sample at any time during the day, without the need for special preparation or fasting.
  • Step 3: Laboratory Analysis - Serum/Plasma: The serum or plasma obtained from the blood sample is tested using quantitative inductively coupled plasma/atomic emission spectrometry. This advanced analytical technique allows for precise measurement of silica levels in the blood.
  • Step 4: Laboratory Analysis - Urine: The urine sample is analyzed using quantitative inductively coupled plasma/optical emission spectrometry. This method provides accurate quantification of silica levels in the urine, helping to assess exposure and potential health risks.

3. Post-Procedure

After the silica testing procedure, there are a few considerations for both the patient and healthcare provider. The blood and urine samples will be sent to a laboratory for analysis, and results are typically available within a specified timeframe, depending on the laboratory's processing capabilities. Patients may be advised to avoid the use of gadolinium contrast media within 48 hours prior to urine sample collection, as this can alter test results. Once the results are available, healthcare providers will review them in the context of the patient's clinical history and symptoms to determine any necessary follow-up actions or treatments based on the silica levels detected.

Short Descr ASSAY OF SILICA
Medium Descr ASSAY OF SILICA
Long Descr Silica
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
Date
Action
Notes
2013-01-01 Changed Medium Descriptor changed.
Pre-1990 Added Code added.
Code
Description
CasePilot

Get instant expert-level medical coding assistance.

Ask about:
CPT Codes Guidelines Modifiers Crosswalks NCCI Edits Compliance Medicare Coverage
Example: "What is CPT code 99213?" or "Guidelines for E/M services"