Why compressed air needs a continuity plan
Compressed air drives instruments, valves, packaging lines, conveying, actuators and many safety-related functions. When it stops, production often stops with it, and in pharmaceutical, food, chemical and process plants the loss can also affect product quality or safe shutdown. Yet many plants treat air as a utility that will “just be there”.
A continuity plan turns a crisis into a procedure. It does not promise fixed recovery times, because those depend on the site, the failure, the season and logistics. What it does is remove the questions that waste the first hours: how much air do we really need, at what pressure and quality, where can we connect a machine, and who has authority to shed load?
Start with the critical-process inventory
List every user of compressed air and rank them. For each critical user, record:
- Minimum flow needed to keep it running safely
- Minimum dynamic pressure at the point of use, in bar and psig
- Required air quality, using ISO 8573-1 classes where relevant
- Maximum tolerable interruption before damage, scrap or a safety issue
- Whether a degraded mode is possible, such as reduced line speed
- Restart priority after air returns
Add these up to get the critical-only demand. Check coincidence – critical users that peak together – and transient demands such as purge cycles. Instrument and control air usually comes first; quality-critical air for product contact comes next; general shop air and cleaning come last and are shed first.
Failure scenarios to plan for
| Scenario | What usually fails | Typical continuity response |
|---|---|---|
| Single compressor loss | Capacity margin | Standby machine; load shedding if margin is thin |
| Multiple compressor loss | Most of the capacity | Rental compressors at a prepared tie-in point |
| Sequencer or controls failure | Coordination | Local pressure bands on each machine |
| Dryer or treatment loss | Air quality | Standby or rental dryer and filters; never bypass for quality-critical users without a decision |
| Electrical feeder or transformer outage | Power to electric compressors | Diesel portable compressors or a DG set sized for compressor starting |
| Cooling-water or ventilation loss | Heat rejection | High-temperature trips; temporary ventilation or air-cooled rental units |
| Main-header or receiver isolation | Distribution | Temporary hose bypass to critical zones |
| Fire, flood or extreme weather | Compressor house access | Machines placed outside the affected area with temporary distribution |
| Fuel or logistics disruption | Diesel units | Refuelling plan and on-site fuel storage within safe limits |
Preparing a temporary-air tie-in point
The single most useful thing most plants can do is install a permanent, isolated connection where a rental compressor can plug in. Without it, hours are lost cutting into pipework during an emergency. A good tie-in point includes:
- A flanged or threaded connection of adequate size, with an isolation valve and a non-return valve, located downstream of where treatment can be added
- Hard-standing nearby for a diesel portable or a containerised electric unit, with access for a truck or crane
- A pressure gauge and drain point at the connection
- Where electric rental is planned, a suitably rated isolator or panel with the cable route known
- Space for a temporary aftercooler, dryer and filters if quality-critical air must be maintained
Record the connection size, the system pressure, the required flow and the treatment needed. That is most of a rental brief, ready before you need it.
Sizing emergency air
- Take the critical-only demand and add a sensible margin for leaks and measurement uncertainty.
- Confirm the pressure at the compressor needed to deliver the minimum pressure at the furthest critical user, allowing for hose and treatment losses.
- Decide on diesel or electric: diesel removes dependence on site power; electric needs a reliable supply that can handle motor starting.
- Match treatment: a refrigerated dryer with a typical PDP around +3 °C for general air, or a desiccant dryer at around −20 °C to −40 °C PDP where the process demands it, plus suitable filtration. Use oil-free machines where the process requires oil-free air.
- Plan for heat and dust: summer ambient in Telangana and Andhra Pradesh is often 40–45 °C, and above 45 °C on open sites, so place machines in shade where possible and away from hot exhausts.
- Plan refuelling, hose routing, operators and service. On long hire jobs we service machines every 300 running hours.
Rental machines are available from 50 to 2,000 cfm and 2 to 30 bar (about 30–435 psig), diesel and electric, so most industrial continuity needs can be matched.
Who decides what: roles and escalation
Emergencies go badly when nobody knows who can authorise load shedding or call in rental. Name, in advance:
- A continuity owner for compressed air
- The production decision-maker who approves load shedding and degraded modes
- The maintenance decision-maker who approves isolation, bypass and tie-in
- The person who calls external support and holds the rental brief
- Who records events and decisions for the review afterwards
Keep the contact list, tie-in drawing, critical-user list and rental brief in one place that can be reached without the plant network.
Testing the plan
A plan on paper often fails at the first real event. Test parts of it during planned shutdowns: run on reduced capacity to confirm load shedding works, check that the tie-in valve opens and the connection fits, confirm the generator can start a compressor motor, and walk the hose route. The resilience testing and emergency drills page covers this in more depth.
Recovery and return to normal
- Confirm the repaired equipment is safe, with protection functions checked.
- Bring permanent machines back while rental units remain connected.
- Verify pressure and air quality, including dryer PDP, before removing temporary supply.
- Isolate and disconnect temporary equipment in a controlled way; drain and depressurise hoses.
- Restore sequencer and controls, then monitoring.
- Review the event: what worked, what took too long, and what to change in the plan.
Common gaps we see in continuity plans
- Critical demand never measured – plans assume the whole installed capacity is needed, so the rental brief is oversized and slower to fill. Logging flow for a few representative days gives a real figure.
- No physical connection point – the plan names a rental supplier but nobody has checked where the hose will join the header or what fitting it needs.
- Treatment forgotten – temporary compressors arrive without a dryer or filters, and wet or oily air reaches instruments or product.
- Power assumptions untested – a DG set that cannot start a large compressor motor, or an electric rental unit with no suitable isolator nearby.
- Standby machine not truly available – the “standby” compressor has been cannibalised for parts or has not run for months.
- Contacts out of date – the emergency list names people who have left, or numbers that are switched off at night.
- Controls dependency – machines that will not run when the sequencer or network is down because local fallback was never configured.
Each of these can be closed at low cost before an emergency. Most need only a site walk, some measurement and a short written brief.
How Reddy Compressors helps
Reddy Compressors, based at Tarnaka, Secunderabad since 2002, is an independent multi-brand compressed-air specialist. We sell new and used compressors, rent from our own fleet of diesel and electric, oil-injected and oil-free machines, and provide service, AMC, breakdown repair, overhauls, audits and spares for ELGi, Atlas Copco, Ingersoll Rand, KAESER, Chicago Pneumatic, Sullair, Doosan, Kirloskar, Gardner Denver and many more. We are not an authorised dealer of these brands. We have tie-ups with all major and reputed brands.
We have supplied compressors on breakdown to leading pharmaceutical manufacturers in Hyderabad and Telangana. For continuity planning we can:
- Visit the site, review critical users and help size minimum survival flow and pressure
- Advise on tie-in point location and size, and on treatment for temporary air
- Supply rental compressors, hoses, aftercoolers and dryers for emergencies and planned shutdowns, with operators where needed
- Coordinate DG sets through Reddy Generators, under the same management, where site power is the problem
- Repair and overhaul failed machines and supply spares identified from the nameplate
Our team of over 20 service engineers and technicians covers all of Telangana and Andhra Pradesh, and we supply equipment and rentals across India.
What to send us
- List of critical air users with minimum flow, pressure and air-quality needs
- Existing compressors and dryers with make, model and capacity
- Main header size and a possible tie-in location (photos help)
- Power availability for electric rental, or space and access for diesel units
- Site address, access restrictions and the contact person for emergencies
Frequently asked questions
What should a compressed-air emergency plan include?
It should list critical air users with their minimum flow, pressure and quality, the load that can be shed, failure scenarios, a prepared tie-in point for rental compressors, power and fuel arrangements, treatment needs, named decision-makers and contacts, and a recovery procedure. Keep it short, printed and reachable without the plant network, and test parts of it during planned shutdowns.
How do I size a rental compressor for a breakdown?
Start from the critical-only demand rather than the full installed capacity, add a margin for leaks, and confirm the pressure needed at the furthest critical user plus hose and treatment losses. Decide diesel or electric based on site power, and match the dryer and filters to the air quality required. Send these details with photos of the tie-in point.
Can we bypass the air dryer during an emergency?
Only as a deliberate, recorded decision and never for users that need dry or quality-controlled air. Wet air can damage instruments, valves and product. Where a dryer fails, a rental refrigerated or desiccant dryer and filters can usually be connected. For general shop air, a short bypass may be acceptable if condensate drains and filters are working well.
Is diesel or electric rental better for emergency air?
Diesel portable compressors are independent of site power, so they suit feeder outages, transformer failures and sites without a spare electrical supply. Electric rental compressors suit long-duration cover where reliable power and a suitable isolator are available, and where noise or exhaust is a concern. Many continuity plans include both options for different scenarios.
Why should we install a permanent tie-in point for rental air?
Because cutting into a live header during an emergency wastes time and adds risk. A permanent valved connection with a non-return valve, hard-standing and access means a rental compressor can be connected as soon as it arrives. It also makes planned shutdowns, overhauls and dryer replacements easier, since temporary air can be brought in without disturbing permanent pipework.
Can Reddy Compressors supply both compressors and generators in an emergency?
Yes. Reddy Compressors supplies rental compressors, hoses and treatment equipment, and Reddy Generators, under the same management, supplies DG sets. Our own projects have included combined temporary power-and-air packages. Availability depends on the duty and the time, so a prepared brief with flow, pressure, quality and site details helps us respond to your request.
Related pages
Technical content reviewed by D. Srinivas Reddy, Managing Partner and service engineer, Reddy Compressors. Last updated 17 October 2026. How our engineering content is reviewed.