Hospital MEP Design — OT HVAC,
Medical Gas & Fire Protection India

Operating Theatre HVAC is the most technically demanding hospital MEP discipline — every parameter (pressure, temperature, humidity, air change rate, filtration class) is a patient safety parameter. KVRM designs OT HVAC to ASHRAE 170 (Ventilation of Health Care Facilities) and NBC 2016 requirements, with the specific parameters for each clinical zone explicitly specified and verified against the standard.

• OT supply: positive pressure (+8 Pa vs corridor), HEPA H14, ≥20 ACH total, ≥5 ACH fresh air
• OT temperature: 18–22°C (ASHRAE 170 range 17–27°C — tighter for general OT)
• OT humidity: 45–55% RH (ASHRAE 170 range 20–60% RH)
• Laminar / ultra-clean ventilation (UCV) canopy design for orthopaedic theatres
• ICU: positive pressure, ≥12 ACH, HEPA filtration, temperature 21–24°C
• Negative pressure isolation rooms — tuberculosis, COVID-19, airborne pathogen control
• NICU: temperature 22–26°C, humidity 40–60% RH, draught-free air supply
• Sterile Services (CSSD): differential pressure, temperature, and humidity control
• Pharmacy clean room: ISO 7/8 classification for aseptic dispensing areas
• Ward, OPD, and diagnostic area HVAC — NBC 2016 compliant conditioning
• Heat load calculations — clinical + equipment + occupancy + solar loads
• BMS controls philosophy — pressure alarms, temperature and humidity monitoring

Medical gas systems are life-critical infrastructure — a failure in piped oxygen supply in an OT or ICU has direct, immediate patient safety consequences. KVRM designs medical gas systems to NFPA 99 (Health Care Facilities Code) and HTM 02-01 (Medical Gas Pipeline Systems), with zone valve boxes, alarm panels, and outlet point schedules for every clinical zone.

• Piped oxygen (O₂) — bulk liquid storage, vaporiser, distribution to all clinical areas
• Nitrous oxide (N₂O) — manifold system, distribution to OT and procedure rooms
• Medical air — oil-free compressor plant, distribution to ICU, OT, and wards
• Surgical air — high-pressure air for surgical tools (7 bar g)
• Vacuum (WAGD / AGSS) — anaesthetic gas scavenging system design
• Medical vacuum — bedside suction points for wards, ICU, and OT
• Zone valve boxes (ZVBs) — isolating each ward/zone for maintenance without shutting entire system
• Alarm panel design — area alarm panels and master alarm panels
• Outlet point schedule — per bed, per zone, per NFPA 99 and NABH requirements
• Pressure drop calculations across all distribution circuits
• Pipeline colour coding and labelling to HTM 02-01 / ISO 32 standards
• Commissioning and pressure testing documentation support

Negative pressure isolation rooms are a critical infection control measure for patients with airborne communicable diseases — tuberculosis, measles, varicella, COVID-19, and other respiratory pathogens. KVRM designs negative pressure rooms to NHS (UK Health Technical Memoranda) and CDC (US Centers for Disease Control) guidelines, which are the most technically detailed standards for this application.

• Negative pressure: −8 Pa relative to corridor (minimum) — continuous monitoring
• Minimum 12 ACH total (ASHRAE 170 / CDC recommendation for isolation)
• All exhaust air directly to outside — no recirculation to general hospital HVAC
• Exhaust HEPA filtration before discharge to atmosphere
• Anteroom design — two-door airlock preventing pressure equalisation during entry/exit
• Continuous pressure differential monitoring — alarm if pressure approaches zero
• Positive pressure protective isolation for immunocompromised patients (reverse isolation)
• Smoke study / CFD analysis to verify airflow patterns (no cross-contamination)
• Commissioning and performance verification protocol

Hospital fire protection follows a defend-in-place strategy — because evacuating patients (especially ICU, OT, or NICU patients) is impractical. This fundamentally changes the fire protection design philosophy: compartmentation, smoke management, and fire detection are as important as suppression. Every hospital fire protection system is designed to NFPA 13, NFPA 101, and NBC 2016.

• Wet pipe automatic sprinkler system — wards, OPD, diagnostics, and support areas (NFPA 13)
• Pre-action sprinklers for server rooms, MRI suites, and radiation therapy areas
• Clean agent suppression for server rooms, pharmacy, and critical electrical panels
• Kitchen hood suppression (NFPA 96) — hospital dietary and kitchen facilities
• Hydrant and hose reel network — campus fire fighting (NBC 2016)
• Fire detection — addressable system, aspirating smoke detection (VESDA) for ICU and OT
• Fire compartmentation and horizontal evacuation zones (NFPA 101 Section 18/19)
• Smoke management — smoke curtains, pressurised escape routes, stairwell pressurisation
• Fire door schedule and compartmentation strategy documentation
• Hydraulic calculations and statutory fire authority submission package

Hospital electrical systems must maintain power to life-critical equipment under any failure scenario — mains failure, DG failure, or distribution fault. Essential and non-essential circuit separation, medical grade isolated power systems (IPS) for OT and ICU, and automatic transfer switching are the core requirements.

• HT/LT power distribution — essential / non-essential circuit separation throughout
• UPS sizing for life-critical systems — ventilators, anaesthesia, monitoring, theatre lighting
• DG set sizing and ATS (Automatic Transfer Switching) for power continuity (NFPA 110)
• Medical grade Isolated Power System (IPS) for OT and ICU — IEC 60364-7-710
• Line Isolation Monitor (LIM) design for OT and ICU panels
• Maintained and non-maintained emergency lighting (NFPA 101 / NBC)
• Nurse call and patient monitoring system infrastructure
• Earthing and lightning protection — IS 3043 / IEC 62305 for hospital campus
• Load flow and short circuit studies (ETAP) for campus HT/LT system

Hospital plumbing must prevent cross-contamination, support infection control, and provide reliable hot and cold water supply to clinical areas — with particular attention to legionella risk management in the hot water system and backflow prevention in clinical sinks.

• Cold and hot water supply — storage, boosting, and distribution design
• Hot water system — centralised calorifiers, legionella risk management (60°C storage)
• Clinical hand-washing facilities — NABH requirements per clinical zone
• Scrub sink design for OT suites — elbow-operated, sensor-operated tap specification
• Sanitary drainage — soil, waste, and vent (SVP) system for multi-storey hospital
• Clinical waste drainage — segregation from general drainage
• Rainwater drainage and storm water management for hospital campus
• Deionised water for sterilisation and dialysis unit water treatment

Hospital MEP has the highest clash density of any building type — medical gas, HVAC ductwork, electrical conduit, sprinklers, and structural elements compete for the same ceiling void. REVIT BIM multi-discipline coordination eliminates clashes before construction begins, reducing site RFIs and programme delays in a sector where delays have clinical consequences.

• REVIT MEP model — all disciplines (HVAC, medical gas, electrical, plumbing, sprinklers) in one model
• Multi-discipline clash detection — interference check reports with RFI register
• Coordinated ceiling plan drawings — congested clinical areas resolved before construction
• Equipment room layouts — plant room coordination, maintenance access verification
• MTO (Material Take-Off) generation for procurement and tendering
• IFC export for structural/architectural coordination and contractor use
• As-built model update post-construction for facilities management