All ASIC mining hardware are air-cooled by design. The design has an intake side and an exhaust side. Cool air is pulled into the miner via the intake fan(s) and exhausted through the rear fan(s) as hot air. Inside the miner is all of the ASIC chips with many heat syncs. The chips use a lot of electricity and as a result produce a large amount of heat. Using the tunnel design the fans are able to cool the chips via convection. 
The ASIC chips inside of a miner are capable of running at incredible hot temperatures without risk of damage. The specifications of a Whatsminer M32 states that the operating temperature is ~35 degrees C (95 degrees F). If the miner exceeds these temperature it will power it self down to avoid damaging itself. The miners are very resilient by design and the firmware protects it self from over heating. If you are finding that the miner is constantly rebooting or turning off then check the logs to verify it is a cooling issue and consider improving airflow.
For smaller mining operations, miners can be placed out in the open recycling air of a single room but this is not sustainable for multiple miners especially in warmer climates. There are 2 main ways we can reduce chip temperatures.
- Increase Airflow passing through the miner
- Reduce the intake air temperature
Increase Airflow passing through the miner
Increasing airflow that passes through the chips and heat syncs will greatly improve the rate at which heat is dissipated .These miners come with fans installed from the manufacture. It is not advised to modify the mining hardware but if you can improve the airflow of the room with external fans you will be able to reduce the chip temperatures.
Reduce the intake air temperature
This may seem obvious as cooler air coming into the miner means cooler air is available to cool down the ASIC chips but what is less obvious is how the hot exhaust air is easily cycled back to the intake side of the miner creating a feedback loop which continuously adds heat back to the miner. To avoid this the air flow needs to be properly managed. If you can separate the intake from the exhaust air then you can greatly reduce the operating temperatures and scale up your mining operation to several machines.
The most important way to manage this is to pull in and exhaust air from 2 different environments or rooms. Separating the intake and exhaust ensures that no hot air is cycling back into the intake side. Depending on how you wish to direct the hot air you can pull fresh air from the outside and pump it into your house or exhaust hot air directly to the outside.