Market Intelligence
Aboveground storage tanks at US commercial sites and inspection demand (estimate)
Size the commercial fuel-tank installed base, separate owner checks from formal inspection work, and turn verified tank sites into a service calendar.
Direct answer
Anvilfield estimates about 409,300 standalone aboveground fuel tanks serving 341,100 US commercial sites in the 2018 reference stock, with an installed-base range of 233,200 to 664,600 tanks. Anvilfield estimates about 32,700 formal tank inspection tasks annually under the central participation and scheduling settings. Size the opportunity by tank, then verify the governing program, operator and inspection calendar at each site.
On this page
How many aboveground tanks serve US commercial sites?What does Anvilfield estimate for tank counts and inspection demand?What counts as inspection demand?How does the governing tank program change the opportunity?How do you turn buildings into a tank register?How do leading inspection teams build a fit-first territory?Where is the included tank stock concentrated?Inspection-market benchmarksWorked example: a regional tank-inspection firm with two inspectorsHow should inspection firms turn the count into a service scope?How does monitoring keep an inspection territory current?Tank inspection opportunity checklistWhich mistakes inflate inspection demand?Which field guides support the resulting tank work?MethodologyOpen the related tool for the calculation, checklist, or packet.
FieldOS by AnvilfieldOffline-first FieldOS for job photos, proof packets, property memory, calculations, teams, billing, and owner-ready reports.Key takeaways
- Anvilfield estimates 409,300 standalone fuel ASTs serving the defined commercial reference stock.
- Central annual workload is 32,700 formal tank inspection tasks and 102,300 outsourced annual-check tasks.
- Routine owner checks, formal tank tasks and contractor site visits require separate counts.
- Public inputs describe 2018 buildings; the 2026 analysis holds that reference stock fixed.
How many aboveground tanks serve US commercial sites?
The fuel-storage segment covers standalone aboveground storage tanks, or ASTs, serving commercial buildings that use fuel oil, including diesel. The companion tank-manufacturer article uses the same segment, keeping product and inspection demand on a common basis.
Count separate fuel tanks serving offices, schools, healthcare, lodging, warehouses and other included commercial activities. Keep buried tanks, integral generator-base storage, water storage, propane pressure vessels, industrial terminals and agricultural tanks outside this calculation. Those populations require their own inventories and inspection programs. A fuel tank serving a commercial building belongs to this segment regardless of whether its duty is heating or backup generation.
Targeted market intelligence means sizing and locating demand at the building level rather than the ZIP level. The national estimate establishes the scale of a defined segment; the local register identifies the actual equipment and purchasing responsibility.
What is targeted market intelligence for building products and servicesStorage tank manufacturers and fabricators: replacement and new-site demandFuel storage tank UST and AST systemsWhat does Anvilfield estimate for tank counts and inspection demand?
Anvilfield research identifies fuel-oil use in 9.9% of the 2018 commercial-building reference stock. Anvilfield estimates 341,100 distinct commercial sites with eligible standalone aboveground fuel storage.
Anvilfield estimates 409,300 installed standalone fuel ASTs and 327,400 tanks participating in formal inspection programs. The installed stock and participating stock have separate rows in the table.
Anvilfield estimates 32,700 formal tank inspection tasks annually, with a range of 9,300 to 132,900, and 27,300 formal inspection site visits. Multiple tank deliverables share a visit when their scheduling and access requirements align.
Anvilfield estimates 409,300 annual owner-check tank tasks and 4,911,200 monthly owner-check tasks per year in the modeled portfolio. A facility employee checks several tanks during a round; each vessel retains its own task record.
Anvilfield estimates 102,300 outsourced annual-check tasks and 135,100 combined contractor tank tasks per year. Formal inspections and outsourced annual checks remain distinct deliverables even when the contractor combines their visits.
Anvilfield estimates 161,500 included tanks in the Northeast, 84,200 in the Midwest, 101,100 in the South and 62,500 in the West. Use the regional stock to organize local research into tank configuration, inspection programs and owner responsibility.
| Anvilfield estimate | Low | Central | High |
|---|---|---|---|
| Fuel-oil buildings / all commercial buildings, % | 9.9 | 9.9 | 9.9 |
| Eligible commercial AST sites | 233,200 | 341,100 | 443,100 |
| Installed standalone fuel ASTs | 233,200 | 409,300 | 664,600 |
| Tanks participating in formal programs | 139,900 | 327,400 | 664,600 |
| Formal tank inspection tasks per year | 9,300 | 32,700 | 132,900 |
| Formal inspection site visits per year | 9,300 | 27,300 | 88,600 |
| Annual owner-check tank tasks | 233,200 | 409,300 | 664,600 |
| Monthly owner-check tank tasks per year | 2,798,400 | 4,911,200 | 7,975,400 |
| Outsourced annual-check tank tasks | 23,300 | 102,300 | 265,800 |
| Combined contractor tank tasks per year | 32,600 | 135,100 | 398,800 |
| Northeast installed tanks | 92,000 | 161,500 | 262,200 |
| Midwest installed tanks | 48,000 | 84,200 | 136,800 |
| South installed tanks | 57,600 | 101,100 | 164,200 |
| West installed tanks | 35,600 | 62,500 | 101,500 |
How to cite this estimate: Anvilfield, Aboveground storage tanks at US commercial sites and inspection demand (estimate), 2026, https://anvilfield.com/field-guides/market-intelligence/aboveground-storage-tanks-at-us-commercial-sites-and-inspection-demand-estimate/
What counts as inspection demand?
Define the deliverable before sizing the service market. Routine owner checks look for visible changes and document the tank and containment condition. Formal inspection work follows the applicable program and calls for the required inspection qualifications, methods and report. Repairs, coating work and engineering evaluations follow separate authorizations.
EPA's bulk-storage inspection guidance distinguishes frequent exterior checks from integrity testing under the applicable industry standard. STI/SPFA's periodic visual-check forms assign work to the owner's inspector without requiring a Certified Inspector. Keep those routine checks separate from formal examinations, specialist methods and the qualifications each requires.
The formal-program fraction represents tanks receiving the modeled formal service, including owner-directed programs. It is separate from the fraction of facilities regulated under the federal Spill Prevention, Control, and Countermeasure program, or SPCC. Record legal applicability as its own field.
A tank task is a deliverable on a particular vessel. A site visit is a mobilization. An account is the organization buying the work. Preserve all of those identities when building a recurring service agreement, especially when a formal inspection and an annual check are performed together.
EPA: Bulk Storage Container Inspection Fact Sheet, August 2013STI: annual inspection checklist, February 2024STI: monthly inspection checklist, February 2024Aboveground storage tank inspection: API 653 and STI SP001| Work stream | Counted unit | Evidence needed before scheduling |
|---|---|---|
| Routine monthly check | Tank check | Owner program, assigned inspector and completed form. |
| Supplemental annual check | Tank check | Applicable annual checklist and equipment testing instructions. |
| Formal inspection | Tank inspection task | Tank record, governing basis, required methods and qualified personnel. |
| Contractor mobilization | Site visit | Co-scheduled tank IDs, access arrangements and agreed deliverables. |
| Repair or coating | Separate project | Evaluated finding and authorized corrective scope. |
How does the governing tank program change the opportunity?
Start with the stored product, construction, configuration, containment and service. EPA's inspection guidance identifies shop-fabricated tanks, small field-erected tanks, portable containers and associated secondary containment within the scope of STI SP001. The standard owner's overview distinguishes periodic, formal external and formal internal inspection work. Similar-looking vessels do not establish the same inspection package.
EPA's applicability guidance uses aggregate aboveground oil-storage capacity greater than 1,320 gallons as a threshold, with qualifying containers of at least 55 gallons included in that calculation and specified exclusions applied. Facility activity, jurisdiction and reasonable discharge potential also matter. Keep the facility applicability decision attached to the plan; a photographed tank or a threshold alone does not establish it.
EPA requires the inspection basis to reflect the container and applicable industry standard. Anvilfield's equivalent formal cycle is a portfolio workload setting. It does not assign a due date, prescribe tank entry or replace the actual standard's inspection schedule.
For each sales opportunity, obtain the tank record and previous report, then ask who owns the inspection calendar. Missing information creates a records-review task. Confirm the required inspection scope before reserving a formal inspector, examination equipment or an outage.
EPA: tank inspections, accessed 2026EPA: SPCC facility applicability, accessed 2026STI/SPFA: What Is SP001?, accessed 2026How do you turn buildings into a tank register?
Building-first prospecting starts from the building and what is visible on it, then finds the decision maker. For tank inspection work, establish the facility boundary and fuel-service relationship before attaching every visible cylinder to the nearest mailing address. Shared plants and neighboring parcels need review.
Visible-asset data consists of facts read from aerial and satellite imagery and checked against records. It provides a candidate tank location, apparent configuration and observation date. Obtain the operator's tank record for stored product, construction standard, capacity and inspection history. An aerial view does not measure corrosion or establish an inspection due date.
Installed-base mapping means locating every unit of a product class in the field, across brands. Give each retained vessel a persistent tank ID beneath a primary facility ID. Link the parcel, building served and operator without making them interchangeable. Keep removed equipment in the history so later observations do not recreate it as a new prospect.
Preserve unresolved candidates in a research queue. A covered tank, an ambiguous circular structure or a shared campus plant needs additional evidence. Record the uncertainty directly and assign the next verification action. The service forecast should contain vessels with a confirmed identity and a defined task.
Building-first prospecting: why the building comes before the contactVisible-asset data: what aerial and satellite imagery can tell a sales teamInstalled-base mapping for equipment manufacturersGenerator fuel system and day tankHow do leading inspection teams build a fit-first territory?
Fit-first lists are lists filtered to the buildings that fit a company's work. Define the service territory, supported tank configurations, required qualifications and access constraints before researching contacts. Keep routine-check support, formal inspection and outage work as separate service views over the same verified register.
Leading manufacturers, distributors and service companies now measure territory coverage directly with building-level data such as PorchRocket's Ground Control, whose commercial-building filters include business type and storage tanks and whose lists arrive within 48 hours after payment. Use the returned sites as a research queue, then confirm the tanks and operator.
For facilities needing a custom tank search, PorchRocket's Asset Search finds assets visible from above and returns the owner of record on each find. Ask the operator who manages the inspection program and purchasing approval before assigning the account to a salesperson.
Release accounts according to the next useful action: obtain the tank register, review the inspection basis, quote a defined task or renew a service agreement. A property owner, operator, environmental manager and procurement office have different roles. Preserve those relationships so a useful site list becomes a usable service book.
Fit-first lists: how to define the buildings that fit your workOwner of record vs operator vs decision maker: who actually buysFind aboveground storage tank inspection prospectsWhere is the included tank stock concentrated?
Anvilfield research places 39.5% of the included tank stock in the Northeast. Use that concentration to prioritize territory research, then compare verified facilities, supported tank configurations and access within the contractor's operating radius.
Use the regional rows to choose where to build a local register. Within a region, compare the supported tank count, ownership concentration and ability to combine visits. A dense territory full of unsupported tank configurations does not fill the right inspector's calendar.
Replace the national eligibility and tank-multiplicity factors with measured local values as the register develops. Record the share of buildings connected to a common fuel plant, the number of eligible tanks at each retained site and the governing program. Preserve the public-input model as a consistent reference.
Keep terminal tank farms, industrial process tanks and public water-storage systems in separate market files. They require different source inventories, equipment qualification and inspection planning. The protective-coatings playbook explains how to connect tank findings to an adjacent service opportunity.
Industrial and protective coatings: finding tanks, steel and structures to coatInspection-market benchmarks
Use these Anvilfield field rules for portfolio planning and record management. The workload ratios use the central settings. A site's confirmed program and inspection history control its actual schedule.
| Quotable field rule | Benchmark | Practical use |
|---|---|---|
| Give every facility a stable identity before counting its tanks. | 1 primary facility ID | Link each vessel, operator and inspection task beneath it. |
| Count formal inspection tasks from the participating stock and cycle. | 80 formal tasks per 1,000 installed tanks annually | Uses 80% participation and a 10-year equivalent cycle. |
| Keep outsourced annual checks visible as their own workload. | 250 annual-check tasks per 1,000 tanks | Uses a 25% outsourcing fraction. |
| Combine task exposure only after preserving each deliverable. | 330 contractor tasks per 1,000 tanks annually | Formal and annual-check tasks; combine visits where appropriate. |
| Translate site coverage into tank workload before staffing. | 9.6 formal tank tasks per 100 verified sites annually | Uses 1.2 tanks per site and the central program settings. |
| A longer equivalent cycle lowers annual formal workload. | 10 to 15 years reduces formal tasks 33.3% | Hold tank count and participation fixed. |
| A change claim needs a dated observation pair. | 2 observations | Preserve the observation interval and asset identity. |
| Record who specifies, authorizes and purchases. | 3 buying roles | Several roles can belong to the same organization. |
| Keep unresolved tank candidates outside the committed calendar. | 0 unresolved tanks in committed work | Retain the missing evidence and next action in the research queue. |
Worked example: a regional tank-inspection firm with two inspectors
A regional tank-inspection firm with 2 inspectors maintains 500 verified sites containing 600 eligible tanks. Its service register separates formal inspection tasks, annual checks and site visits, with the actual program and due-date evidence attached to each vessel.
Anvilfield analysis puts that portfolio's annual exposure at 48 formal tank inspection tasks and 150 outsourced annual-check tasks, for 198 contractor tank tasks. Grouping work at 1.2 tanks per visit produces 40 formal site visits and 125 annual-check visits before combining compatible visits.
The resulting 165 separate task visits give the service manager a starting workload to reconcile with the actual calendar. Review each tank's due date, required method, prior findings and access. Several deliverables performed during the same mobilization remain separately identifiable in the report and task register.
Divide the work by qualifications and route before assigning it to the inspectors. A periodic annual-check visit and a formal examination package consume different resources. Entry, cleaning, specialist examinations and repair evaluation need their own scope and staffing. The task count supports capacity planning; the actual method and site conditions establish hours.
Close the planning loop by comparing authorized tasks, completed tank reports and actual mobilizations. Use that record to replace the equivalent cycle, outsourcing fraction and grouping factor at the next portfolio review.
| Anvilfield case estimate | Calculation |
|---|---|
| Verified sites | Case register |
| Eligible tanks | 500 x 1.2 |
| Formal-program stock | 600 x 80% |
| Formal tank tasks | 480 / 10 years |
| Formal visits | 48 / 1.2 |
| Outsourced annual checks | 600 x 25% |
| Annual-check visits | 150 / 1.2 |
| Combined contractor tasks | 48 + 150 |
| Separate task visits | 40 + 125, before combining visits |
How should inspection firms turn the count into a service scope?
Build the proposal around the tank register and specified deliverables. State which owner checks, formal inspections, examination methods, containment observations, equipment tests and reports are included. Identify the qualifications and responsibilities attached to each task. Count equipment first, then estimate the work.
Resolve access, operating restrictions, missing design records and the authorization process for additional evaluations before quoting a fixed package. Keep cleaning, internal access, outage coordination and repair work as explicit line items where applicable. The national estimate supplies task exposure; a documented site scope supplies the price basis.
For findings that lead to coating or lining, carry the tank ID, service, preparation requirements and acceptance records into the repair procurement file. A coating opportunity remains a separate purchasing decision. Connect cathodic-protection findings and electrical issues to the appropriate specialist rather than burying them in a general tank allowance.
Tank coating bids: build the scope before pricing the liningStorage tank coating and interior liningCathodic protection and corrosion controlHazardous classified locationsHow does monitoring keep an inspection territory current?
Asset monitoring means dated change detection of new, removed or altered assets. Keep a baseline tank register and compare later observations with the same facility and vessel identities. A new visible tank prompts a record request; a removed tank prompts a service-calendar review.
Inspection managers use PorchRocket's Asset Search for custom finding and monitoring of tanks visible from above, with pricing scoped to the search. Specify the territory and changes that matter, then reconcile each result with the operator's equipment register.
Preserve the date of each observation and the date the operator confirms the change. The first observed appearance establishes an observation boundary; the commissioning record establishes entry into service. Avoid transferring an old inspection date or agreement to replacement equipment without review.
Use monitoring to maintain prospect coverage and trigger qualification. Keep the formal inspection calendar linked to the responsible program and inspection records. A stable aerial appearance supplies no evidence that a required inspection has been completed.
Asset monitoring: tracking new, removed and altered assets over timeTank inspection opportunity checklist
Complete this account handoff before releasing work into the committed service calendar.
Want this checklist to run itself on every job — with photo proof and a signed record crews can hand the customer? That's FieldOS.
Which mistakes inflate inspection demand?
The largest counting mistake is treating every fuel-oil building as a separate aboveground tank site. Shared fuel service reduces the site count, while multiple standalone vessels increase the tank count. The model applies those conversions in sequence so the inspection workload follows vessels rather than addresses.
Another mistake is counting routine checks as certified-inspector jobs. Owner-performed check volume shows program activity; contractor demand depends on outsourcing and formal-program participation. Preserve those factors separately when comparing service territories.
Do not add every monthly check to the contractor pipeline or count a combined visit as several mobilizations. Likewise, do not convert an inspection finding directly into a repair order. Maintain the difference between an asset, a task, a visit and an authorized project.
Finally, keep the reference year attached to every quoted estimate. The public inputs measure the 2018 building stock. Anvilfield's analysis is dated 2026 and applies no stock-growth adjustment. A current territory forecast uses the verified equipment register, actual inspection dates and recorded purchasing decisions.
Methodology
Public inputs: EIA 2018 Table C33 reports 583,000 fuel-oil buildings: Northeast 230,000; Midwest 120,000; South 144,000; West 89,000. Table B1 reports 5,918,000 commercial buildings. CBECS excludes storage tanks themselves as buildings; these counts supply the denominator for Anvilfield tank conversion settings. S3 defines the commercial frame; S4 to S9 establish inspection scope, applicability and owner-check tasks.
Research notes, November 5, 2026. Hold the 2018 stock fixed. Eligible sites equal fuel-oil buildings x distinct-site factor x standalone-AST eligibility. Installed tanks equal eligible sites x tanks per site. Apply the same stock settings regionally. The bounds combine the listed settings; they are model scenarios rather than survey confidence intervals.
Formal-program tanks equal installed tanks x formal participation. Annual formal tasks equal that participating stock divided by the equivalent cycle, with due dates staggered evenly. Formal visits equal formal tasks divided by tanks per visit. This aggregate cycle represents a mixed portfolio; actual programs establish the required inspection types and dates.
Apply full monthly and supplemental annual check coverage to retained tanks. Annual owner-check tasks equal installed stock; monthly tasks equal stock x 12. Outsourced annual tasks equal annual tasks x outsourcing fraction. Combined contractor tasks equal formal tasks plus outsourced annual tasks. Preserve both deliverables when visits coincide. The model assigns no outsourced monthly-check workload, inspection price or repair conversion.
The worked firm has 2 inspectors, 500 verified sites and 1.2 tanks per site. Apply the central formal and outsourcing settings and group annual-check tasks at 1.2 tanks per visit. Count separate visits before combining compatible work. Calculate before rounding: national counts round to the nearest 100, shares to a decimal place, and the case retains whole tasks and visits. The benchmark sensitivity changes only the equivalent cycle from 10 to 15 years.
For replacing territory settings with measured site coverage, PorchRocket's Ground Control publishes commercial-building list prices of $10 to $20 each. These national estimates use the saved public inputs and Anvilfield research settings; the product supplies a separate building-level research workflow.
PorchRocket Ground Control: live commercial-building offerPorchRocket pricing: Subscribe & save tiersPorchRocket Asset Search: live tank-search offerS1: EIA Table C33, 2018 fuel-oil buildingsS2: EIA Table B1, 2018 commercial buildingsS3: EIA CBECS terminologyS4: EPA tank inspectionsS5: EPA bulk-storage inspection fact sheetS6: EPA SPCC applicabilityS7: STI/SPFA SP001 overviewS8: STI annual inspection checklistS9: STI monthly inspection checklist| Anvilfield research setting | Low | Central | High |
|---|---|---|---|
| Distinct fuel-service sites per fuel-oil building | 0.80 | 0.90 | 0.95 |
| Share of sites with eligible standalone ASTs | 50% | 65% | 80% |
| Eligible tanks per retained site | 1.0 | 1.2 | 1.5 |
| Installed tanks participating in formal programs | 60% | 80% | 100% |
| Equivalent formal inspection cycle, years | 15 | 10 | 5 |
| Co-scheduled tanks per formal site visit | 1.0 | 1.2 | 1.5 |
| Annual owner checks outsourced | 10% | 25% | 40% |
FAQ
How many aboveground storage tanks does Anvilfield estimate at US commercial sites?
Anvilfield estimates 409,300 standalone aboveground fuel tanks serving 341,100 commercial sites in the 2018 reference stock. The installed-tank range is 233,200 to 664,600. Methodology records the population and conversion settings.
Is this an estimate of every aboveground tank in the United States?
It covers standalone fuel ASTs serving the defined commercial-building population. Water storage, propane pressure vessels, industrial terminals, agricultural tanks, buried tanks and integral generator-base storage need separate inventories. Retain those boundaries when quoting the estimate or comparing it with another tank-market study.
How many formal tank inspections does the model support annually?
Anvilfield estimates 32,700 formal tank inspection tasks annually, with a range of 9,300 to 132,900. A tank's governing program and prior inspection records establish its actual scope and due date.
Does every AST require an annual certified inspection?
Inspection type, timing and qualifications depend on the tank and governing program. STI's monthly and annual periodic visual-check forms describe work by an owner's inspector without requiring a Certified Inspector. Keep those routine tasks separate from formal inspections and obtain the applicable standard for the actual scope.
Why are tank inspection tasks different from site visits?
A task belongs to a particular tank and deliverable; a visit is a mobilization that combines compatible work at a location. Anvilfield estimates 32,700 formal tank tasks and 27,300 formal site visits annually in the central portfolio.
Are the low and high estimates statistical confidence limits?
They combine the listed site, storage-eligibility, tank-multiplicity, program, cycle and outsourcing settings. They are scenario bounds. The estimates retain the 2018 reference stock without a growth multiplier; local verified registers replace the conversion settings for account and staffing decisions.
Can aerial imagery establish compliance or the next inspection date?
Use imagery and records to locate candidate assets and preserve dated observations. Obtain tank identity, construction, service, governing basis and inspection history from the operator's records. Formal evaluation and scheduling require the applicable program and qualified personnel; a visible tank outline does not supply them.
How should a service manager use the combined contractor workload?
Use the central 135,100 annual contractor tank tasks as national exposure within the stated segment and settings. It combines formal tasks with outsourced annual checks. Qualify supported tanks locally, confirm purchasing authority and contracts, and combine compatible visits while preserving each authorized deliverable.
People also ask
Sources checked
- S1. EIA CBECS Table C33 2018 data; December 2022 release. PDF pages 1 and 2: 583,000 fuel-oil buildings and regional counts of 230,000 Northeast, 120,000 Midwest, 144,000 South and 89,000 West. Quantitative starting populations, not tank counts. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S2. EIA CBECS Table B1 2018 data; September 2021 release, December 2022 revision. PDF page 1: 5,918,000 commercial buildings, used only as the fuel-oil building-share denominator. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S3. EIA CBECS terminology 2018 survey definitions; live page accessed 2026. Buildings exceed 1,000 square feet; storage tanks themselves and manufacturing and agricultural activities are excluded; fuel oil includes diesel. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S4. EPA tank inspections Live guidance accessed 2026. Distinguishes industry-standard integrity inspections and the SP001 tank and containment scope. No stock conversion or inspection cycle supplied. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S5. EPA Bulk Storage Container Inspection Fact Sheet August 2013 publication. Pages 1 and 2 distinguish routine checks and formal inspection work; current planning settings do not adopt the older document's standard-specific interval tables. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S6. EPA SPCC facility applicability Live guidance accessed 2026. Aboveground aggregate capacity greater than 1,320 gallons, qualifying containers at least 55 gallons, exclusions, facility activities and reasonable discharge potential. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S7. STI/SPFA: What Is SP001? Live standard-owner overview accessed 2026. Periodic and formal inspection distinctions and scope. No universal formal cycle or participation share supplied. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S8. STI SP001 annual inspection checklist February 2024, seventh edition. Page 1: annual visual check supplements monthly checks and does not require a Certified Inspector. Task format only; full-stock adoption is Anvilfield's research setting. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S9. STI SP001 monthly inspection checklist February 2024, seventh edition. Page 1: monthly periodic visual checks, owner's inspector and individual tank identification. Task format only; no national check adoption statistic. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S10. PorchRocket Ground Control Live product page accessed 2026. Commercial-building filters include business type and storage tanks; lists within 48 hours after payment. No vendor data used in the national tank estimate. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S11. PorchRocket Asset Search Live product page accessed 2026. Custom finding and monitoring of assets visible from above, owner-of-record results and scoped pricing. No dollar price or tank-count input attributed to the service. Downloaded and opened with curl on November 5, 2026; HTTP 200.
- S12. PorchRocket pricing Live pricing reference checked for the November 2026 edition. The commercial-building list offer in this article is documented on S10, Ground Control.