Warehouse temperature and humidity

In Uzbekistan the temperature inside a warehouse can climb above forty degrees in summer, while in winter in unheated hangars it can fall to freezing. Spring rains and roof leaks raise the humidity as well. The difficulty is that damage from heat and moisture does not show at once: chocolate turns white, cardboard softens, cement hardens, medicine loses potency, yet this is usually discovered only after a customer complains. If you do not measure, the damage builds up silently. Below are practical recommendations for controlling it.

What each product is sensitive to

Take the permitted temperature and humidity of each product from its packaging or the manufacturer's paperwork. The general picture is this:

• medicines and cosmetics: the temperature condition on the pack is strict, and in heat potency falls;
• food: in heat chocolate turns white and oil goes rancid, in damp conditions flour and grain go mouldy;
• cement, plaster and plasterboard: they draw in moisture and harden or lose strength;
• water-based paint, glue and glass cleaner: after freezing, the quality is spoiled;
• electronics: moving from freezing cold into a warm room produces condensation inside, and batteries suffer in heat;
• paper, cardboard, parquet and laminate: they swell or soften as humidity changes;
• metal goods: they rust in damp air.

When choosing a storage place, put the most sensitive goods in the most stable spot: the middle of the warehouse, away from the floor and from the roof.

What to measure and where

A single thermometer only shows the average temperature of the room. In reality a warehouse has microclimates: hot under the roof, a draught by the door, cold and damp near the floor, heat by a window the sun shines through. So place sensors in several spots: in the places you think are hottest and coldest, in the centre, and beside the most sensitive goods.

An inexpensive thermo-hygrometer (it shows temperature and relative humidity) will do, but a sensor that records the data itself is better: it logs once every half hour and works at night and at weekends. If you observe by hand, write in the log at least twice a day (in the morning and in the hot part of the day).

After a week of measuring, draw a map of the warehouse's hot and damp spots. Unexpected places often turn up: for example, shelves under the roof are hotter than the outdoors for half the day.

What to do in heat, cold and damp

In heat

Painting a metal roof white and insulating under it noticeably lowers the temperature inside. Night-time air exchange (while keeping the building secure) cools the warehouse. Cover windows the sun shines through with curtains or film. Put goods on a pallet, not straight on the floor. Move the unloading and dispatch of sensitive loads such as dairy products and medicines to the cool morning hours. Air conditioning belongs in the zone that needs it, not across the whole warehouse.

In cold

Move goods that fear freezing to a heated place or set aside a separate heated corner in the warehouse. Do not unpack electronics brought on a cold truck at once: until it warms to room temperature, condensation can form, so wait a few hours.

In damp

Keep cement and plaster on a pallet away from the wall, not directly on the floor. Check after rain whether the roof is leaking. In a damp warehouse dehumidifiers and moisture absorbers help, and ventilation is a free tool. Wrap moisture-sensitive goods in film.

The log, the limits and responsibility

Measuring by itself changes nothing; it needs a decision. Write a lower and an upper limit for each product group. It should be clear in advance who does what when a limit is exceeded: a responsible employee is named and the procedure for moving or checking goods is written down. Record every excursion in a log: when, for how long, which goods, what decision (check, quarantine, sale).

The log has another benefit: it provides evidence. For example, if 18 days of readings show more than six hours a day above 35 degrees under the roof, it is easy to justify moving sensitive goods or insulating the roof. And a sensor usually costs far less than one spoiled batch.

Conclusion

Temperature and humidity are a source of invisible losses: if you measure them, set limits and keep a log, you can stop the damage long before the complaints. During a warehouse audit, SkladKontrol examines storage places and conditions and helps find cases where sensitive goods are standing in the wrong place.