RWD R600-O2-4E Precision Oxygen Flowmeter Expansion Module

Overview

The RWD R600-O2-4E is a precision-engineered oxygen flowmeter expansion module designed for integration into RWD small and large animal anesthesia delivery systems. It operates on the principle of variable-area (rotameter) flow measurement, where gas flow lifts a calibrated float within a tapered glass or polymer tube; the float’s equilibrium position corresponds linearly to volumetric flow rate under defined pressure and temperature conditions. This mechanical analog method delivers high repeatability and minimal electronic dependency—critical for fail-safe operation in preclinical surgical environments. The module is not a standalone anesthesia unit but functions exclusively as an auxiliary flow control interface, enabling precise titration of supplemental oxygen upstream of the vaporizer. Its design supports dual-gas configurations when paired with the R600-N2O-4E nitrous oxide flowmeter, facilitating controlled O₂/N₂O blending prior to volatile anesthetic introduction.

Key Features

• Calibrated flow range of 0.1–1.0 L/min with ±5% full-scale accuracy across standard operating conditions (20 °C, 101.3 kPa, dry gas)
• ISO 407 (DIN 13258) miniature medical gas outlet interface—ensuring interoperability with globally recognized anesthesia equipment standards
• Robust mounting architecture compatible with both RWD A600 series small animal and B600 series large animal anesthesia machine bracket systems
• Chemically resistant wetted materials: borosilicate glass float tube, stainless steel mounting hardware, and medical-grade silicone O-rings
• No internal electronics or power requirement—mechanical operation enhances reliability and simplifies maintenance
• Modular form factor allows installation without modification to existing RWD anesthesia platform firmware or pneumatic layout

Sample Compatibility & Compliance

The R600-O2-4E is validated for use with medical-grade oxygen (USP/EP grade) and is rated for continuous operation at inlet pressures up to 500 kPa (72.5 psi). It is not intended for use with flammable, corrosive, or particulate-laden gases. All materials in contact with the gas stream comply with ISO 10993-1 (Biological Evaluation of Medical Devices) for cytotoxicity and extractables. The device conforms to ISO 8536-4 (Infusion equipment — Part 4: Infusion sets for single use) for dimensional and functional interchangeability of gas connectors. While not a Class II medical device per FDA 21 CFR Part 860, its design aligns with IEC 60601-1 general safety requirements for ancillary anesthesia accessories used in laboratory animal facilities operating under AAALAC-accredited protocols.

Software & Data Management

This is a purely mechanical flow control module with no embedded microcontroller, digital display, or data output interface. Flow rate is read visually via engraved scale markings on the tube housing, referenced against the meniscus of the float. As such, it generates no electronic data logs, requires no software drivers, and introduces zero cybersecurity or validation overhead in GLP/GMP-regulated preclinical labs. Its simplicity eliminates the need for 21 CFR Part 11-compliant audit trails—making it suitable for institutions maintaining paper-based or manually recorded anesthesia records per institutional animal care and use committee (IACUC) SOPs.

Applications

• Supplemental O₂ delivery during low-flow or closed-circuit anesthesia in rodent, rabbit, and non-human primate models
• Independent titration of oxygen concentration in N₂O/O₂ balanced mixtures to maintain normoxia while minimizing hypoxic risk
• Flow calibration verification against primary mass flow controllers in multi-gas anesthesia test benches
• Teaching laboratories requiring transparent, real-time visualization of gas flow dynamics for physiology and pharmacology instruction
• Backup flow regulation in dual-vaporizer setups where independent gas source control improves procedural flexibility and safety redundancy

FAQ

Is the R600-O2-4E compatible with non-RWD anesthesia machines?

Yes—provided the host system features ISO 407 inlet ports and mechanical mounting provisions matching the R600 series bracket footprint (120 × 60 mm, M4 threaded holes). Adapter kits are available upon request.
Can this flowmeter be sterilized using autoclaving?

No. The glass float tube and silicone seals are not autoclave-rated. Cleaning is limited to 70% isopropyl alcohol wipe-down and compressed air purging between uses.
What is the recommended recalibration interval?

RWD recommends annual verification against a NIST-traceable reference flowmeter under controlled lab conditions (23 °C ± 1 °C, 50% RH), especially after mechanical impact or prolonged exposure to humidified gas streams.
Does the module include tubing or mounting hardware?

Mounting screws and alignment spacers are included. Tubing (8 mm OD inlet, 6 mm ID outlet) must be sourced separately to meet facility-specific biocompatibility and gas compatibility requirements.