What a Delhi medical gas brief usually looks like
Very little medical gas work in Delhi is greenfield. The typical brief is a hospital that has grown its critical care capacity two or three times over on a distribution system originally sized for a much smaller, ward-weighted bed mix. Somewhere in the building there is a 22 mm branch feeding a floor that now has twelve ventilated beds on it, an oxygen manifold that was adequate in 2015, and an alarm panel with two zones that nobody has calibrated since installation.
The 2020-21 oxygen crisis changed the money but not always the engineering. The national PSA rollout added generation capacity quickly, and a large installed base of those plants across the NCR was never properly integrated with the downstream pipeline, the reserve manifold or the master alarm system. A plant that cannot hold delivered pressure at the furthest ICU outlet under full diversified load is capacity on paper. Auditing that gap — measuring actual pressure at the remote terminal under load rather than reading the plant gauge — is the honest first step on most Delhi projects.
Retrofitting gas in a hospital that cannot close
Delhi hospitals have no swing capacity — no empty floor to decant a ward into, and a referral load from Uttar Pradesh, Bihar and Haryana that does not pause for construction. Every retrofit is therefore a live-building exercise, and the method matters more than the material.
We work zone by zone against the existing area valve service units, establish temporary cylinder-based supply for affected beds before any isolation, and execute tie-ins in short, pre-agreed windows — usually overnight, agreed in writing with nursing, biomedical and infection control. Every isolation runs under a permit-to-work with a named authorised person. Nitrogen-purged silver brazing is non-negotiable in occupied buildings, both for internal cleanliness and to avoid oxide debris travelling downstream into terminal units. No zone returns to clinical use until it has been pressure tested, purged, cross-connection tested and gas-identity verified terminal by terminal, with the results documented.
Budget realistically for this. Live-building working typically adds 15 to 30 percent to the labour line against the same scope on an empty slab, and it lengthens the programme more than it inflates the cost.
Plant room siting where there is no land
The hardest question on a Delhi MGPS project is frequently not the pipework at all — it is where the plant goes. Ground-level enclosures are ideal and rarely available. Terrace installation works where the structural engineer certifies the load. Basement plant rooms are common in Delhi and entirely workable, provided ventilation, heat rejection and real maintenance access for compressor and dryer service are engineered rather than assumed.
Three checks should happen before the plant location is fixed: PESO separation distances if there is a liquid oxygen tank in the scheme, electrical and DG headroom for the compressor load, and whether pipework can reach the existing main without routing through occupied clinical space. Discovering the third one late has derailed more schemes than any technical failure.
Sizing for a Delhi bed mix
Delhi’s tertiary hospitals run ICU and theatre fractions well above the national average, which pushes almost every sizing assumption. We size to HTM 02-01 design flows per terminal type, apply diversity by department rather than across the building, and apply essentially no diversity to ICU oxygen or to 7-bar surgical air. Oxygen follows the NFPA 99 three-source philosophy — primary, secondary and reserve, plus an emergency supply connection point accessible from outside the building, which in a dense Delhi site needs a fire-tender-accessible location identified early. Medical air and vacuum plants are duplex or triplex so any unit can be serviced while the remainder carry full diversified load, with automatic changeover annunciated at the master panel.
Vacuum deserves specific mention because it is the most frequently undersized service in Indian hospitals. Delhi’s long horizontal runs in wide floor plates degrade vacuum faster than intuition suggests, and the pipeline must still hold a minimum of minus 400 mmHg at the terminal under full diversified load.
Approvals and the standards that apply
There is no single mandatory MGPS engineering code in India, so the working stack is HTM 02-01 for sizing and testing methodology, NFPA 99 for source redundancy and installer or verifier qualification, and ISO 7396-1 with ISO 9170-1 terminal units and ISO 5359 hoses for component certification. NABH publishes no engineering code of its own — it audits whether you can prove design to a recognised standard, which is why the validation dossier matters as much as the installation.
On the statutory side, Delhi means PESO for bulk liquid oxygen, DPCC consent where plant or DG capacity changes, Delhi Fire Service NOC covering plant room rating and fire-barrier penetration sealing, DDA or MCD sanction where built-up area changes, and an update to Delhi Nursing Homes registration where bed capacity or service scope moves. PM-ABHIM funded critical care blocks and central government hospital procurement both carry their own documentation and inspection formats on top.
Delivering MGPS in Delhi from Pune
To be clear about what we are: RayMedico Projects has one office, in Pune. No Delhi office, no NCR team, no permanent North India presence. Our model for Delhi is a deployed site team, and for gas work specifically that structure matters more than it does for most trades.
- Load survey within 6 to 8 working days, department by department, including measured pressure at remote terminals under load where an existing system is in scope. That measurement is usually the most valuable output of the visit.
- Qualified brazers stationed on site for the continuous installation duration, with brazing qualification records in the handover dossier. Medical gas brazing is not work you subcontract to whoever is available locally.
- Consolidated copper and component consignments planned against the installation sequence over roughly 1,400 km and three to four days road transit, with degreased tube kept capped in transit and in storage.
- An enlarged critical-spares handover — terminal unit cartridges by gas type, AVSU spares, alarm sensors, regulator and changeover spares — sized for a hospital that cannot wait two days for a part.
- Training for your biomedical and engineering staff on permit-to-work discipline, alarm response and first-line fault clearance, plus defined AMC response windows written into the contract instead of implied. From 1,400 km away, an honest window beats an optimistic promise.
Getting the numbers right early
Two things decide whether a Delhi MGPS budget survives contact with reality: an accurate outlet schedule by department, and an early decision on source strategy. Below roughly 50 oxygen-dependent beds a good automatic manifold with reserve is usually the rational choice; between 50 and 150, PSA generation typically pays back in two to four years given stable power and adequate plant room ventilation; above that, liquid oxygen as primary with PSA or manifold backup is more robust. Decide it on a modelled load profile, not on capital cost alone.
For the full technical detail — gas-by-gas design flows, sizing methodology, testing regime and certification — see our medical gas pipeline system service page.