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As the first images of changes done to #HagiaSophia's interior to prepare for the prayers marking the conversion of Hagia Sophia to a mosque, let me share some initial observations, insights, and worries with you. A thread 
It appears that the authorities have chosen to install a (presumably retractable) curtain mechanism to conceal the mosaics of Virgin and Child on the apse, and the Archangel Gabriel in the bema.
Unless the Turkish authorities have discovered a system that defies gravity, and flies in mid-air on its own, the 6 sail-like curtains of #HagiaSophia hang from a mechanism, possibly attached to somewhere in the bema vault or within the apse.
A couple of worries here: the choice of materials for the curtain is crucial. Is the fabric concealing #HagiaSophia's mosaics fire retardant? Is it evaluated for pest control and dust accumulation?
There seems to be a circular rod placed within the apse of #HagiaSophia, which I assume will function to retract the curtains back once the prayers are over. I am assuming that there must be a remote control system to the curtains, which needs some sort of electricity and wiring.
Worst of all, #HagiaSophia's walls were drilled to secure this system in several locations. The extra weight of the curtains & retractable mechanism will put extra stress on the ancient building, and can cause significant structural damage in the long term.
I cannot see the hook holding up the curtain system in the photos of #HagiaSophia. However, any material introduced to ancient structures needs to be carefully evaluated. Metals corrode, corrosion causes structural irreversible damage.
In case you were wondering how the curtain system was installed, here is a shot of the installation crew up on the scaffolding built into the apse of #HagiaSophia. The center hook for the system appears to be drilled in somewhere in the bema vault.
Let's look at the turquoise carpets covering #HagiaSophia's marble floor. Again, the choice of material for carpets (and their underlayment) is crucial: they need to be fire-retardant, pest-proof and they should not trap moisture.
We do not whether any of these concerns were discussed with experts for the choice of #HagiaSophia's carpet. However we know for sure that #Erdogan was consulted...
The carpet salesperson stated that #Erdogan choose the turquoise color for #HagiaSophia's carpet, and demanded the use of domestic wool (as opposed to higher quality New Zealand wool, suggested by the carpet salesperson). https://odatv4.com/amp/kiblede-biraz-problem-var-20072041.html
The omphalion of #HagiaSophia, where the Byzantine emperors were crowned, is not covered. Velvet ropes restrict access to it, however I am not sure how much protection they would offer during crowded prayer times.
I am not sure what the brown section is. Is it a temporary addition for the ongoing work or a ceremonial accessory for tomorrow? It is perpendicular to prayer-lines of the carpet, possibly a processional way for #Erdogan to make his entry to #HagiaSophia? We will see tomorrow.
There was only 14 days between #Erdogan's signing of the decree to convert #HagiaSophia into a mosque and the first prayers. 14 days is NOT enough to adequately consider, discuss and deliberate with experts to find the best alternatives for the changes necessitated by conversion
I will repeat: when we are dealing with ancient buildings we need to carefully assess all risk factors. Decisions given in haste, without adequate consultation&deliberation with experts will cause irreversible damage. #HagiaSophia is almost 1500 years old and fragile.
