Crystalline Silica Testing Lab Houston, TX
As Houston's premier crystalline silica testing lab, our AIHA IHLAP-accredited industrial hygiene testing laboratory at 10200 East Freeway, Houston TX 77029 provides XRD (NIOSH 7500 / OSHA ID-142 v4) analysis with full polymorph speciation for quartz, cristobalite, and tridymite. FTIR (NIOSH 7602) is also performed in-house but is not within the AIHA IHLAP-accredited scope. AIHA IHLAP LAP-101470 and ISO/IEC 17025:2017 accredited — continuous AIHA accreditation since 2000. Personal exposure monitoring, respirable dust gravimetric analysis, and bulk material quantification — OSHA 1910.1053 and 1926.1153 compliant results accepted nationwide.
Silica exposure is invisible — only air monitoring confirms your controls work
OSHA Enforcement
OSHA 1910.1053 and 1926.1153 carry penalties up to $16,131 per violation per day. Construction employers who skip Table 1 compliance or fail to monitor face stop-work orders and criminal referrals.
Silicosis Prevention
Silicosis is incurable and progressive. RCS particles that reach the alveoli trigger permanent fibrosis. OSHA's PEL of 50 µg/m³ was set precisely because lower concentrations still cause disease over a working lifetime.
Legal & Liability Shield
Workers' comp and tort claims for occupational silicosis are increasingly successful. Documented, accredited IH testing history from an ISO/IEC 17025 lab is your primary legal defense against exposure claims.
Baseline Assessments
Employers are required to assess the exposure of each employee who is or may reasonably be expected to be exposed to RCS at or above the action level (25 µg/m³).
What Is Crystalline Silica (RCS) Testing?
Crystalline silica is a mineral found in sand, stone, concrete, mortar, and many industrial materials. When workers cut, grind, drill, blast, or crush these materials, they generate airborne particles small enough to penetrate deep into the lung — called Respirable Crystalline Silica (RCS).
Silica testing measures the exact airborne concentration of RCS in the breathing zone of workers using personal sampling pumps, cyclones, and pre-weighed PVC filters. Our crystalline silica testing laboratory analyzes these filters via X-Ray Diffraction (XRD) or Infrared Spectroscopy (FTIR) and reports results in µg/m³ for direct comparison to the OSHA PEL (50 µg/m³) and Action Level (25 µg/m³). As an AIHA IHLAP-accredited IH testing lab (LAP-101470) operating under ISO/IEC 17025:2017, AGT Labs provides crystalline silica analysis using XRD (NIOSH 7500 / OSHA ID-142 Version 4) — our AIHA-accredited primary method — and FTIR (NIOSH 7602) as an in-house non-accredited alternative.
- Airborne RCS monitoring via XRD (NIOSH 7500 / OSHA ID-142 Version 4) — AIHA IHLAP-accredited
- Total and respirable dust gravimetric analysis (NIOSH 0500/0600)
- Bulk material characterization for silica content
- Quantification of specific polymorphs — Quartz, Cristobalite, and Tridymite
- Defensible data for OSHA "Table 1" compliance alternatives
- Federal & DoD project support — AIHA IHLAP + ISO/IEC 17025 quality system
Our Silica & Dust Testing Methods
As a specialized crystalline silica testing lab, we know that choosing the correct analytical method is critical for regulatory compliance. Workers exposed to crystalline silica are often co-exposed to nuisance particulate. For gravimetric analysis of non-silica fractions, see our total and respirable dust testing services.
XRD Silica Analysis — AIHA IHLAP Accredited
X-Ray Diffraction (XRD) is the gold standard for crystalline silica analysis and AGT Labs' AIHA IHLAP-accredited primary method. It measures the specific crystalline structure of the particles, allowing accurate quantification of Quartz, Cristobalite, and Tridymite, even in the presence of interfering minerals.
FTIR Silica Analysis
Fourier Transform Infrared Spectroscopy (FTIR) measures the absorption of infrared light by silica bonds. It is a valid alternative analytical technique to XRD but is more susceptible to interferences from other minerals (like certain silicates or amorphous silica) present in the dust.
⚠ Non-accredited: FTIR (NIOSH 7602) is performed in-house but is not within our AIHA IHLAP-accredited scope. For accredited compliance reporting, use XRD (NIOSH 7500 or OSHA ID-142 v4).
Respirable & Total Dust
Gravimetric analysis to determine the total mass of dust collected. We highly recommend pairing Respirable Dust (NIOSH 0600) with your Silica XRD analysis to get a complete picture of the worker's exposure profile from a single filter.
Bulk Silica Quantification
Determines the exact percentage of crystalline silica in raw bulk materials — concrete, grout, sand, stone, aggregate, or industrial minerals. Required when an employer needs to characterize the silica content of materials before beginning work, or for SDS compliance documentation.
Quick Method Selector — Which silica test do you need?
XRD vs FTIR — Which Method Should You Specify?
Both methods are NIOSH-validated for crystalline silica air analysis, but they have important differences in capability, sensitivity, and accreditation status. Here's the side-by-side decision framework.
| Capability | XRD (NIOSH 7500) | FTIR (NIOSH 7602) |
|---|---|---|
| NIOSH Method | NIOSH 7500 + OSHA ID-142 v4 | NIOSH 7602 |
| AIHA IHLAP scope (LAP-101470) | Accredited | Not accredited — in-house only |
| Detects Quartz (α-SiO₂) | Yes — quantitative | Yes — quantitative |
| Detects Cristobalite | Yes — quantitative | No — unreliable |
| Detects Tridymite | Yes — quantitative | No — unreliable |
| Typical LOD per filter | ~5 µg quartz | ~10 µg quartz |
| Headroom vs OSHA AL (25 µg/m³ at 800 L) | ~4× below AL | ~2× below AL |
| Interference resistance | High — distinguishes by crystal structure | Moderate — silicates & amorphous SiO₂ can interfere |
| OSHA & MSHA acceptance | Both accept (preferred) | Both accept (alternate) |
| Foundry / Kiln environments | Required | Not suitable |
| Construction (concrete, mortar, brick) | Recommended | Acceptable (non-accredited) |
| Bulk material analysis | Yes — % by polymorph | Limited — quartz only |
| Combined with NIOSH 0600 dust gravimetric | Yes — same filter | Yes — same filter |
When to specify XRD over FTIR
Default to XRD for any environment where cristobalite or tridymite may be present — foundries, refractory ceramics, calcined diatomaceous earth, kiln operations, and any process involving heating silica-bearing materials above 870°C. NIOSH considers cristobalite more biologically reactive than quartz with a lower REL (25 µg/m³ vs 50 µg/m³). FTIR cannot reliably detect cristobalite — using it in foundry environments produces falsely low results that under-estimate the worker's true exposure to the more potent polymorph.
FTIR is acceptable for known-quartz-only environments — typical residential construction, simple concrete cutting on standard Portland cement, and bulk material screening where polymorph speciation is not required. AGT Labs offers FTIR at slightly lower cost when XRD is not required, but note: FTIR is performed in-house and is not within our AIHA IHLAP-accredited scope. For accredited compliance reporting, use XRD.
Detection Limits & Sample Volume Planning
What sample volume do you need to certify a result below the OSHA Action Level (25 µg/m³)? Here's the headroom each method provides at typical full-shift sample volumes.
| Sampling Scenario | Cyclone | Volume | XRD LOD (µg/m³) | vs OSHA AL (25 µg/m³) | vs OSHA PEL (50 µg/m³) |
|---|---|---|---|---|---|
| 4-hr Partial Shift | Dorr-Oliver Nylon @ 1.7 L/min | 408 L | ~12 µg/m³ | ~2× below AL | ~4× below PEL |
| 8-hr Full Shift | Dorr-Oliver Nylon @ 1.7 L/min | 816 L | ~6 µg/m³ | ~4× below AL | ~8× below PEL |
| 8-hr Full Shift | SKC Aluminum @ 2.5 L/min | 1,200 L | ~4 µg/m³ | ~6× below AL | ~12× below PEL |
| 8-hr Full Shift | BGI GS-3 @ 2.75 L/min | 1,320 L | ~4 µg/m³ | ~6× below AL | ~12× below PEL |
| FTIR (non-accredited) — 8-hr Full Shift | Dorr-Oliver Nylon @ 1.7 L/min | 816 L | ~12 µg/m³ | ~2× below AL | ~4× below PEL |
| Bulk Material XRD | n/a — bulk sample | ≥ 1 g sample | ~0.1% by weight | n/a | n/a |
Why volume matters more than method
For documented compliance below the OSHA Action Level, target at least 800 L of sample volume — this gets you to a ~6 µg/m³ XRD reporting limit, providing 4× headroom below the 25 µg/m³ AL. Partial-shift sampling (under 4 hours) often produces volumes too low to certify a non-detect against the AL, leaving the result inconclusive.
If you must use partial-shift sampling for short-duration tasks, switch to a higher-flow cyclone (SKC Aluminum at 2.5 L/min or BGI GS-3 at 2.75 L/min) to compensate. Critical: never substitute one cyclone's flow rate for another — this invalidates the particle size cut-point and renders the sample unusable. For accredited compliance reporting, use XRD only — FTIR results are in-house non-accredited and should not be cited as IHLAP-accredited.
Three Regulated Silica Polymorphs We Identify
Not all silica is the same. Polymorph identity matters for regulatory treatment, health risk assessment, and which analytical method reliably detects each form. XRD (NIOSH 7500) identifies all three — FTIR (NIOSH 7602) detects quartz only.
OSHA Table 1 — Construction Tasks & Required Controls
OSHA 29 CFR 1926.1153 Table 1 lists 18 construction tasks with prescribed engineering controls. Full implementation = exemption from baseline air monitoring. Partial implementation, deviation, or unlisted tasks require objective air monitoring data — that's where AGT Labs' XRD analysis comes in.
| Construction Task | Required Engineering Control | Respirator if < 4 hrs/day | Respirator if ≥ 4 hrs/day |
|---|---|---|---|
| Stationary masonry saws | Integrated water delivery system | None required | None required |
| Handheld power saws | Integrated water delivery system | None outdoors / APF 10 indoors | APF 10 (filtering facepiece N95 or half-mask) |
| Walk-behind saws | Integrated water delivery | None outdoors | None outdoors / APF 10 indoors |
| Drivable saws (outdoor) | Integrated water delivery | None | None |
| Rig-mounted core saws/drills | Water-fed tooling | None | None |
| Handheld & stand-mounted drills | Shroud + dust collector (≥ 25 CFM/inch) | None | None |
| Dowel drilling rigs (concrete) | Shroud + dust collector + HEPA-filtered vacuum | APF 10 | APF 10 |
| Vehicle-mounted drilling rigs | Dust collector + control booth | None | None |
| Jackhammers & handheld powered chipping tools | Water OR dust collector (HEPA-filtered) | None outdoors / APF 10 indoors | APF 10 (half-mask required) |
| Handheld grinders for mortar removal (tuckpointing) | Shroud + HEPA-filtered dust collector | APF 10 | APF 25 (full-face PAPR) |
| Handheld grinders (other than mortar removal) | Water OR shroud + HEPA dust collector | None outdoors | None outdoors / APF 10 indoors |
| Walk-behind milling machines & floor grinders | Water OR HEPA dust collection | None | None |
| Small drivable milling machines | Water-fed cutting drum | None | None |
| Crushing machines | Water spray + ventilated booth | APF 10 | APF 10 |
| Heavy equipment in earthmoving | Enclosed, climate-controlled cab | None | None |
| Heavy equipment for demolition / abrasive blasting | Enclosed cab + water suppression | APF 10 | APF 25 (full-face PAPR) |
| Abrasive blasting (silica sand) | Banned in EU/UK; restricted in US | Substitute with non-silica abrasive OR conduct exposure assessment | |
When you need air monitoring instead of Table 1
Three common scenarios force you out of Table 1 and into mandatory air monitoring: (1) the task isn't on Table 1 (e.g., scarifying, demolition of pre-1981 silica-bearing materials, mineral processing); (2) the engineering control specified can't be implemented (no water available, dust collector below required CFM, etc.); or (3) general industry work covered by 29 CFR 1910.1053 — Table 1 does NOT apply to general industry. In any of these cases, full-shift personal XRD monitoring documents your compliance status and protects you in the event of an OSHA inspection.
Every Method, Every Standard, Every Deliverable
No surprises in your silica testing report. Here's exactly what each analysis from our industrial hygiene testing lab returns — methods, media, and deliverables side by side.
| Analysis Type | Method / Standard | Sample Media | Report Deliverable | Rush? |
|---|---|---|---|---|
| Crystalline Silica — XRD (Accredited) | NIOSH 7500 / OSHA ID-142 v4 | 37mm PVC filter (5.0 µm) + cyclone | µg/sample quartz + cristobalite + tridymite · TWA · PEL comparison · AIHA IHLAP-accredited | Yes |
| Crystalline Silica — FTIR (In-house non-accredited) | NIOSH 7602 | 37mm PVC filter (5.0 µm) + cyclone | µg/sample quartz · TWA · PEL comparison · NOT within AIHA IHLAP scope | Limited |
| Respirable Dust Gravimetric | NIOSH 0600 | Pre-weighed PVC filter + cyclone | mg/m³ total respirable dust · OSHA PEL comparison | Yes |
| Total Dust Gravimetric (PNOR) | NIOSH 0500 | Pre-weighed PVC filter (no cyclone) | mg/m³ particulate not otherwise regulated | Yes |
| Dual: Dust + XRD Silica | NIOSH 0600 + NIOSH 7500 | Single pre-weighed PVC filter + cyclone | mg/m³ respirable dust + µg/m³ silica per polymorph · both PEL comparisons | Yes |
| Bulk Silica Content | XRD / NIOSH 7500 (Mod) | Bulk material (powder, chunk) | % crystalline silica by weight · polymorph breakdown | Call |
Turnaround Times & Free Sampling Media
Every rush option and kit detail — clearly laid out before you submit your first sample.
| Turnaround Option | Timeline | Surcharge |
|---|---|---|
| Standard Analysis | 7+ Business Days | No Surcharge |
| 4-Day Rush | 4 Business Days | +25% |
| 3-Day Rush | 3 Business Days | +50% |
| 2-Day Rush | 2 Business Days | +75% |
| 1-Day Rush | 1 Business Day | +100% |
Sampling Media & Equipment
- Pre-weighed 37mm PVC filters (5.0 µm pore size)
- Matched weight filter pairs for gravimetric QA
- Dorr-Oliver nylon cyclones (1.7 L/min)
- SKC aluminum cyclones (2.5 L/min)
- Calibrated personal air sampling pumps — loaner program
- Field blank filters (10% of batch, pre-labeled)
- Pre-paid UPS return shipping label
- Industrial Hygiene Chain of Custody form
Silica Sampling Field Requirements
Silica testing is unforgiving of poor field protocol. Using the wrong flow rate for your specific cyclone will invalidate the particle size cut-point, rendering the data useless for OSHA compliance. Full reference: IH Sampling & Analysis Guide.
From Sample Collection to Final Report
Request Kit & Pumps
Contact us to request pre-weighed PVC filters, cyclones, and loaner pumps. We ship nationwide.
Collect Air Samples
Deploy pumps on workers using exact flow rates required by your specific cyclone type.
Ship to IH Lab
Keep cassettes upright. Complete COC with flow rates and total volumes. Ship to our Houston IH testing lab.
Gravimetric & XRD
We weigh the filters for total respirable dust, then perform XRD analysis for specific silica polymorphs.
Compliance Report
Receive your detailed report comparing detected concentrations against OSHA PELs via our secure portal.
OSHA Silica Regulations Explained
The 2016 OSHA Silica Rule drastically lowered permissible exposure limits. Here is how our IH testing services help you comply. Foundry and metalworking operations that generate silica dust from grinding or sandblasting may also require a full metals in air ICP scan and mercury vapor testing to evaluate concurrent metal fume and vapor exposure.
Who Relies on Our Crystalline Silica Testing Lab
Many construction and demolition sites pair silica monitoring with asbestos testing, PCB testing, and PAH testing to satisfy OSHA, EPA NESHAP, and TSCA requirements under a single chain of custody.
Construction & Concrete Work
GCs, subcontractors, and concrete cutting specialists — silica monitoring for OSHA 1926.1153 Table 1 alternatives, saw cutting, coring, grinding, and jackhammering operations. Renovation projects involving composite wood products may also require formaldehyde testing to address concurrent indoor air hazards.
Oil & Gas / Hydraulic Fracturing
Frac sand handling, blending, and pumping operations generate some of the highest silica exposures measured in any industry. OSHA 1910.1053 baseline and periodic monitoring for well-site supervisors, blender operators, and sand transfer crews.
Foundries & Metal Casting
Foundry operations using silica sand molds generate cristobalite and tridymite — polymorphs that FTIR misses. XRD (NIOSH 7500) with full polymorph reporting is essential for OSHA 1910.1053 compliance in iron, steel, and aluminum foundry environments.
Abrasive Blasting Operations
Sand blasting, shot blasting, and surface prep contractors — Texas OSHA-regulated environments where exposures can exceed the PEL by 10–50× without proper controls. Surface coating operations following blasting may also require isocyanate exposure monitoring for polyurethane and epoxy applications.
Industrial Hygiene Consultants
Environmental and IH consulting firms across Texas, Gulf Coast, and nationwide — bulk sample and IH testing analysis with accredited XRD results, complete with TWA calculations and OSHA PEL comparisons formatted for client reports and citations defense.
Ceramics, Glass & Mining
Ceramics and glass manufacturing (cristobalite and tridymite risk), stone quarrying, and surface mining — MSHA and OSHA 1910.1053 compliance monitoring. Bulk silica content characterization for raw materials and SDS documentation.
Federal & DoD Facilities
BRAC remediation, federal building demolition, military airfield concrete work, navy shipyard abrasive blasting, and DoD environmental cleanup require accredited silica analytical data. Our AIHA IHLAP accreditation (LAP-101470) and ISO/IEC 17025:2017 quality system support federal facility silica testing under TSCA, CERCLA, and DoD environmental data quality requirements.
Silica Testing — Frequently Asked Questions
What is the OSHA PEL for respirable crystalline silica?
What methods does your crystalline silica testing lab use?
Do you provide cyclones and sampling pumps?
What is the required air volume for silica sampling?
When is silica air testing legally required?
Can you analyze both respirable dust and silica from the same filter?
What turnaround times do you offer for silica testing?
What is the difference between Quartz, Cristobalite, and Tridymite?
Is AGT Labs accredited for crystalline silica testing?
What is OSHA Table 1 and how does it relate to silica monitoring?
What is the difference between the OSHA Action Level and PEL for silica?
What are the detection limits for XRD vs FTIR silica analysis?
How long are silica samples stable in shipping?
Does AGT Labs perform silica testing for federal projects and DoD facilities?
Crystalline Silica Lab Serving Houston's Industrial Base
AGT Labs is located at 10200 East Freeway, Suite 101, Houston TX 77029 — within the Houston Ship Channel industrial corridor. All XRD and FTIR silica analysis is performed in-house. No send-outs. Samples received before 2:00 PM CST logged same day.
Accredited
Quantified by XRD
TAT Available
10200 E. Freeway
Ready to Partner with an Accredited Crystalline Silica IH Testing Lab?
AIHA IHLAP (LAP-101470) · ISO/IEC 17025:2017 · XRD (NIOSH 7500 / OSHA ID-142 v4) AIHA-accredited · FTIR (NIOSH 7602) in-house non-accredited · Pump Loaner Program · Rush 1-Day TAT · Houston TX 77029