# Article: Why Tropical Climate Makes Indonesian Cleanroom Design Different

## Brief Introduction
​A lot of cleanroom designs brought over from Europe or Singapore check all the boxes on paper, but run into trouble once commissioned in Indonesia.

## Main Content


A lot of cleanroom designs brought over from Europe or Singapore check all the boxes on paper, but run into trouble once commissioned in Indonesia. Many overseas designers size their HVAC systems around temperate conditions, and they don’t fully account for what persistent heat and high humidity do to a clean facility day in and day out.



Moisture is the main pain point. In rainy seasons, outdoor relative humidity can hang above 80% for weeks straight. If the dehumidification section is undersized, condensation builds up at panel seams, inside ducts, or even on HEPA unit housings. It’s not just about RH going out of spec. Those hidden wet spots invite mould and microbial growth, something BPOM auditors pick up quickly in CPOB inspections. Some contractors skimp on dehumidification capacity to lower upfront cost, and the factory ends up with unstable environmental logs and repeated non-conformities.



Power supply is another easy thing to overlook. Voltage drops and brief blackouts still happen in plenty of industrial zones. A standard western setup loses its pressure cascade fast when the AHU goes down. Once gradients fail, unfiltered outside air can backflow into Grade C or D zones. For sterile pharma lines, even a short disruption can put an entire batch at risk. We bring up backup air handling and continuous monitoring early during design, not as a last-minute add-on.



Material choices also need adjusting. Standard cleanroom coatings and sealants that hold up well in drier climates break down faster here. Silicone seals degrade quicker under constant heat and moisture. Floor joints, coved corners and drain traps need extra care. A drain without a proper water seal and insect barrier becomes a contamination risk — we see this noted again and again in BPOM audit reports.

Clients sometimes mistake this problem for just needing bigger air conditioners. It is not. The whole control priority shifts. In cooler regions, designers focus mostly on temperature and air change rates. Here, latent moisture load becomes the dominant design factor. Cranking up air changes will not stop condensation. We split sensible cooling and latent load control, and build enough flexibility for both dry and wet seasons.

We also run into clients who copy the exact ISO class from their overseas plant, without updating their monitoring plan. Higher baseline humidity means microbial sampling schedules often need to be tightened. Surface alert and action limits shouldn’t simply be copied from a European site’s SOP.



ISO 14644 and CPOB themselves do not change because of the climate. The standards remain the same. But how you hit those stable parameters is different. A cleanroom that passes all acceptance tests in Germany may need costly rework to operate reliably in Jakarta or Surabaya.

When we start planning a new facility, we always separate two questions: what regulation requires, and what local climate loads the HVAC has to handle. Skip the second part, and you are looking at unstable operation, higher ongoing maintenance, and audit findings long after construction wraps up.