is it safe to clean up img/tmp ?

[Beeta]

running out of inodes...

[11:48][[email protected] tmp]# ls /home/nginx/domains/xxxx.xxx/public/img/tmp | wc -l
27886

[11:48][[email protected] tmp]# df -i
/dev/sda       3260416 3251877    8539  100% /

is it safe to delete all the content of img/tmp (without touching index.php)?

[DRMasterChief]

Maybe this is a fundamental question.
Can the thirtybees developers please tell us what can be easily deleted from time to time?
I don't use invoice creation in the shop or inventory management, I keep deleting orphaned shopping carts, I hope that's OK.
What else can be deleted?

[DRMasterChief]

There is information about deleting files for PrestaShop, but what about the current thirtybees versions 1.5.1 and 1.6.x?