Peep at 12.24 psi. Subtle swelling noted, no deformation
Peep at 7.33 psi. Significant swelling, deformation caused by constraints of the decompression chamber. First sign of skin fracture.
Peep at 2.46 psi. Maximum vacuum obtainable in decompression chamber. Peep swelled to fill ~83.25% of available chamber volume. Surface tension causes multiple skin fractures, revealing rich creamy goodness inside. Image noticeably washed out, possible due to either camera flash or low rate alpha particle decay of test subject. Note that by mass, Peeps are 13% Peeptonium-114, an unstable isotope of Peeptonium-112 with two extra peeptons.
Peep returned to ambient pressure (14.7 psi). Skin deformation still evident, elastic limits of protective pink covering clearly reached. Doctor Johnson noted "It looks like a circus peanut." Inner surface of decompression container coated with thin layer of peeptic oxide, further evidence of peepton emission at 2.46 psi.
Compression cycled peep next to unmolested control peep. Test subject contracted to ~63.55% of original volume.