Wear something over your chest or whatever part of yourbody you feel is sensitive to the sun when it is irritated.
What time of day do you walk to work?
What oils are you using on your body? This is when I would caution against olive oil and even coconut oil for some people, both make my skin worse in the sun. Jojoba is the only one that does not seem to effect the way the sun tans my skin, I also make sure not to wash off all of my healthy natural skin oils by showering too often or in hot water or using soaps, soap is reserved for neither regions only and only when necessary.
When skin is irritated by the sun you can rub cucumber or fresh aloe on it to soothe add moisture, let that soak in and dry and then rub in copious amounts of oil, helps to hAve a cloth specifically for oils to lightly wipe off the excess but for the most part let your skin absorb what it will.
Are you staying properly hydrated? It's beneficial to eat really hydrating things like melons, cucumbers, cactus pads n fruit which will give you a ton of watr and minerals like potassium and silica, great for hydration and skin healing, also melon seeds are high zinc and lose phytates then any other seeds, which will promote healing and prevention of sunburn
