How Spare Air Works

How Spare Air Works

Understanding your Spare Air emergency breathing device is essential for safe operation. This page explains the components, operation, and best practices for using your Spare Air in emergency situations.

Spare Air Component Diagram

Spare Air Component Diagram - Technical Drawing

Component Breakdown

A. Mouthpiece

High-quality silicone mouthpiece designed for comfort and secure grip during emergency use. The ergonomic design allows for quick insertion and reliable seal, even in stressful situations.

B. Purge Button

Clears the regulator of water and empties the cylinder when needed. Press the purge button before breathing to ensure clear airflow. This is the same proven technology used in full-size SCUBA regulators.

C. Serial Number

Unique identifier for your Spare Air unit. Record this number for warranty registration, service tracking, and hydrostatic test documentation. Each serial number is traceable to manufacturing date and quality control records.

D. Regulator

Our simple, rugged design utilizes the same time-proven technology found in typical regulators used by SCUBA divers around the world. Our always-on, breathe-on-demand, balanced single-stage regulator is easy to maintain and service.

Key Features:

  • Always-On Design: No switches or valves to fumble with in an emergency
  • Breathe-On-Demand: Air flows only when you inhale, conserving your air supply
  • Balanced Single Stage: Consistent breathing effort from full to empty
  • Field Serviceable: Simple design allows for easy maintenance and repair

E. Refill Port and Cap

Spare Air is refillable from your own SCUBA cylinder or through 3 other methods via the refill port. The protective cap keeps the port clean and prevents contamination. Learn about all refill options.

F. Pressure Indicator

Standard Pin Style Indicator: Easy to read – pin will be flush with the surface when the unit is full at 3000 PSI. As air is used, the pin extends outward.

Optional Dial Gauge: Features an easy-to-read, color-coded display for at-a-glance pressure checks in both PSI and BAR. Green zone indicates full pressure, yellow indicates partial fill, and red indicates low pressure requiring refill.

G. 3000 PSI Aluminum Cylinder

This DOT/TC approved SCUBA cylinder is manufactured just like standard SCUBA cylinders, with the same safety features and rigorous testing protocols.

Safety & Compliance:

  • Manufactured from 6061 aluminum to DOT Specification 3AL
  • Each cylinder is hydrostatically tested before leaving our facility
  • Individually stamped with test date and specifications
  • Must be visually inspected annually
  • Must be hydrostatically tested once every 5 years
  • View our DOT/TC certifications

H. VIP Sticker

Displays the month and year of the last cylinder visual inspection. This annual inspection ensures the cylinder interior is free from corrosion, contamination, and damage. Always check that your VIP is current before diving.

See Spare Air in Action

Emergency Ascent from 75 Feet

Do you have a minute to spare? Watch this demonstration showing how to use Spare Air in an emergency ascent from 75 feet.

Key Takeaways from the Video:

  • Spare Air provides sufficient air for a controlled emergency ascent from recreational diving depths
  • Proper breathing technique (slow, controlled breaths) maximizes air duration
  • Always perform a safety stop when possible, even in emergency situations
  • Practice with your Spare Air in controlled conditions to build muscle memory

How to Use Spare Air in an Emergency

  1. Locate Your Spare Air: Keep it mounted in an easily accessible location on your BCD or body
  2. Grab and Position: Bring the unit to your mouth with the mouthpiece facing you
  3. Purge (Optional): Press the purge button briefly to clear any water from the regulator
  4. Insert Mouthpiece: Place the mouthpiece in your mouth and seal your lips around it
  5. Breathe Normally: Take slow, controlled breaths – do not hold your breath
  6. Begin Ascent: Start a controlled ascent at a safe rate (30 feet per minute maximum)
  7. Exhale Continuously: If air supply runs out during ascent, exhale continuously to prevent lung overexpansion
  8. Surface Safely: Complete your ascent and signal for assistance if needed

Important: Never hold your breath while ascending. Expanding air in your lungs can cause serious injury.

Frequently Asked Questions

How long does Spare Air last?

Air duration depends on depth, breathing rate, and cylinder size. At the surface, a 3.0 cu ft Spare Air provides approximately 57 breaths. At 33 feet (2 ATA), this reduces to approximately 28 breaths. In an emergency, controlled breathing and immediate ascent maximize your air supply. View our complete air duration chart.

How often should I refill my Spare Air?

Check your pressure indicator before every dive. Refill when pressure drops below 3000 PSI. Even if unused, cylinders can lose pressure over time due to temperature changes or minor seal weepage. Always dive with a full cylinder.

Can I refill Spare Air myself?

Yes! Spare Air can be refilled from your own SCUBA tank using the included refill adapter. You can also use a hand pump, scuba shop fill station, or our optional electric compressor. Learn about all refill methods.

What maintenance does Spare Air require?

Spare Air requires minimal maintenance:

  • After Each Use: Rinse with fresh water and allow to air dry
  • Annually: Visual inspection (VIP) by a qualified technician
  • Every 5 Years: Hydrostatic test as required by DOT regulations
  • As Needed: Replace mouthpiece, O-rings, or other wear components

View complete maintenance guidelines.

Is Spare Air approved for airline travel?

Empty Spare Air cylinders are generally permitted in checked baggage when completely depressurized and the valve is visible for inspection. Regulations vary by airline and country. Always contact your airline in advance and arrive early for inspection. Read our complete travel guidelines.

What's the difference between Spare Air models?

Spare Air is available in multiple sizes (1.7, 3.0, and 6.0 cubic feet) to suit different diving profiles and preferences. Larger models provide more breaths but add weight and bulk. The 3.0 cu ft model is our most popular choice, balancing portability with adequate emergency air supply for recreational diving. Compare all Spare Air models.

Can Spare Air be used for surface swimming or snorkeling?

While Spare Air is designed for SCUBA diving emergencies, it can provide emergency air for surface swimmers, snorkelers, or anyone working in or around water. However, it is not a substitute for proper swimming ability or safety equipment.

Does Spare Air work in cold water?

Yes, Spare Air functions in cold water conditions. However, like all regulators, extreme cold can affect performance. If diving in water below 50°F (10°C), consider having your regulator serviced with cold-water compatible components and lubricants.

How deep can I use Spare Air?

Spare Air can be used at any recreational diving depth. However, remember that air consumption increases with depth due to increased pressure. Plan your dives conservatively and always maintain adequate primary air supply. Spare Air is an emergency backup, not a primary air source.

Is Spare Air CE certified for use in Europe?

Yes! Spare Air and HEED 3 are CE certified under Notified Body 0598, meeting European Union safety and environmental requirements. View all our certifications.

What if my Spare Air won't deliver air?

If your Spare Air fails to deliver air:

  • Check that the cylinder has pressure (check the pressure indicator)
  • Ensure the refill port cap is securely tightened
  • Try pressing the purge button to clear any blockage
  • If still not working, switch to your buddy's alternate air source and surface safely
  • Have the unit inspected by a qualified technician before using again

Can I service Spare Air myself?

Basic maintenance like rinsing and mouthpiece replacement can be done by the user. However, internal regulator service, O-ring replacement, and cylinder inspections should be performed by qualified technicians familiar with SCUBA equipment. Improper service can compromise safety.

Safety Reminders

⚠️ Important Safety Information:

  • Spare Air is an emergency backup air source, not a substitute for proper dive planning
  • Always dive with adequate primary air supply and monitor your pressure gauge
  • Never hold your breath while ascending – always exhale continuously
  • Practice using Spare Air in controlled conditions before relying on it in an emergency
  • Ensure your Spare Air is properly maintained and inspected according to schedule
  • Check pressure before every dive – never dive with a partially filled cylinder

Related Resources

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