Glossary · Case & Dial
Helium escape valve
A one-way valve fitted to some diving watches to release helium absorbed during saturation diving.
Explanation
The helium escape valve is a one-way valve on saturation diving watches that lets helium, which seeps into the case during long dives in helium-rich breathing gas, escape during decompression instead of blowing the crystal off. Rolex (with COMEX) and Doxa developed the first versions around 1967–71. For ordinary diving it is unnecessary but harmless.
In the object catalogue
Catalogued objects whose own source record mentions “Helium escape valve”. The quoted line shows where; it is the seller’s or museum’s wording, not independent verification.
Wristwatch
Rolex Sea-Dweller 'Tropical', Reference 1665
“This is a stainless steel Rolex Sea-Dweller diver's wristwatch, Reference 1665, catalogued by the source as dating to circa 1971. Known to collectors as a 'Double Red' due to tw…”
Wristwatch
Omega Seamaster Diver 300M Ref. 210.60.42.20.99.001
“Helium escape valve crown visible at the 10 o'clock position and winding crown at 3 o'clock”
Wristwatch
Rolex Comex Submariner Ref: 5514/5513 Automatic Diver's Wristwatch
“This lot features a Rolex Comex stainless steel automatic diver's wristwatch, reference 5514/5513, dated by the auction house to January 1972. The source states the watch featur…”
Wristwatch
Rolex Sea-Dweller Ref. 16660 'Militarized DLC'
“This Rolex Sea-Dweller, reference 16660, is a customized timepiece dating to 1987. Originally produced as a stainless steel, self-winding diver's watch, the object has been modi…”
Wristwatch
Rolex Oyster Perpetual Date Sea-Dweller Ref. 16600
“This Rolex Sea-Dweller, reference 16600, is a stainless steel diver’s wristwatch manufactured in 2002. The watch features a self-winding mechanism, center seconds, and a date di…”
Wristwatch
Girard-Perregaux Sea Hawk Pro 1000m
“This Girard-Perregaux Sea Hawk II, reference 49950, is an automatic wristwatch with a 44mm stainless steel case. It features a unidirectional rotating elapsed-time bezel and an …”