My allergies are triggered by cleaners and stuff in the air and 'just kuz' for no apparent reason (also have vasomotor rhinitis & chronic sinusitis). Had to throw out several pillows 'cause the stuff living in my nose <gross> degraded the silicon!
Here's what's working for me:
Humidifier tub daily
7th Generation for dishes unscented soap & water, soak while showering, scrub with fingers, rinse.
While wet spray with white vinegar (the cheap kind 5%), let sit 1-2 minutes, rinse very very well, let air dry on clean washcloth on nightstand.
Squirt above soap into each pillow and scrub with fingers, let sit on sink all soapy while showering, rinse very well. If not perfectly clear, dissolve 1/4 teaspon bromelan powder (it's from pineapples, find at heath food stores as loose powder) in hot water then add pillows and let soak 10-60 mins until clear when rinsed. This is the only thing that has worked to keep the pillows clean and free of something that will set my allergies off. I do not soak these in vinegar as the residue set off my allergies.
Weekly: 2-6ft hoses, ResMed humidifier cover & gasket
Soak in 7th Gen soap and water, rinse. Hang hose to dry for 8-10 hrs, then put on machine & let dry for 10 -15 mins, hang for use. Air dry cover & gasket.
Every other wk or thereabouts: headgear & plastic holder of pillows
Soak in 7th Gen soap and water, rinse, hang to dry.
Note: I tried washing the pillow suport more often without an improvement, so I quit washing so often; if I get a cold, I wash this daily.
Check filter and replace if needed (mine are not washable).
Nasal irrigation with Grossan gadget & solution when really congested. While it sounds disgusting (sorta like a WaterPik for nose) & ya gotta figure out the angles inside your nose, it's actually pleasant when ya get the hang of it.
1 spray each nostril Astepro (new addition that's working so far to keep nose decongested)<fingers crossed>, chew gum to mask yukky taste. It congests me for about an hr and then clears up. I'm guessing my nose doesn't like the sucralose...why didn't they use Xylitol which isn't a nasal tissue irritant and starves the bugs that live in noses/sinuses? <dummies>
Spray each nostril once with Nasonex, wait 5 mins for it to dry. Put on mask. Check humidifer setting: if humidity is high, turn to 2 or lower; if low, increase; if have rainout or wet pillows, turn lower. So far I've not had to add a hose cover but it doesn't get really really code here and my hose is partly under my bed covers or pillow (depending on which side I'm sleeping on).
My CPAP sits on a library step (those 1-step 'thingees') next to the head of my bed keeping it up off the floor & it's dust, etc.
If my nose is dry, I use saline sprays. Because I drink lots of water, I seldom need the saline spray.
Never, never, never, never say never.