Sechrist's current site and its March 2026 catalog say 33, 36 and 41 inches; the older catalog our table was built from says 32.50 and 35.50 inches.
The two sets of figures
Sechrist's product page and its Hyperbaric Chamber Product Catalog (part number 100641 REV 0, dated March 2026, hosted on sechristusa.com) both give interior diameters as round inch figures. The older H Chamber catalog our comparison rows were transcribed from gives them to two decimal places, and the numbers do not agree for the 3300H or the 3600H. Both documents are Sechrist's.
| Model | H Chamber catalog (the figure in our table) | sechristusa.com and March 2026 catalog, read 31 August 2026 |
|---|---|---|
| 3300H | Internal diameter 32.50 in | Interior Diameter 33" |
| 3600H | Internal diameter 35.50 in | Interior Diameter 36" |
| 4100H | Internal diameter 41.00 in | Interior Diameter 41" |
No operating pressure in the current documents
Neither the product page nor the 18-page March 2026 catalog states a chamber operating pressure. Searching the full text of both for “ATA” and “psig” returns nothing in either. The 30.0 psig / 3.0 ATA figure in our table comes from the older catalog only. Both current documents do publish occupant weight ratings: 500 lb standard with a 700 lb option on the 3300H, and 700 lb standard on the 3600H and 4100H.
How our table handles it
Both diameters are shown, each attributed to the document it came from, because picking one would mean deciding which of a manufacturer's own publications to believe. A 0.5 inch discrepancy does not change which chamber fits a room. It does tell you that a Sechrist specification is worth confirming in writing against the serial number you are actually being sold.
What it means if you are buying
Ask Sechrist or the dealer to confirm interior diameter and maximum operating pressure in writing for your specific model, because the manufacturer's own current documents do not state the pressure at all.
How this was verified
The Sechrist product page was fetched and its raw markup searched on 31 August 2026. The Hyperbaric Chamber Product Catalog PDF was downloaded from sechristusa.com and its full text searched the same day; its footer reads “P/N 100641 REV 0 (March 2026)”. The older H Chamber catalog figures were transcribed on 28 August 2026 and are unchanged.
Sources
- Sechrist Industries — HBO products pageSource read on 31 August 2026 · Interior diameters and occupant weight ratings. No occurrence of “ATA” or “psig” anywhere in the document.
- Sechrist Industries — Hyperbaric Chamber Product Catalog, P/N 100641 REV 0 (March 2026), PDFSource read on 31 August 2026 · 18 pages. Repeats the round-inch diameters. Publishes accessory list prices but no chamber price and no chamber operating pressure.
- Sechrist Industries — ‘H’ Chamber catalog (the source our existing rows were transcribed from)Source read on 28 August 2026 · Third-party host. Retained only because it is the document the two-decimal figures and the 30.0 psig figure came from.